
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.
10 (Dec 2014 to Feb 2015)
22
June 2015
Revision 1
Main Contractor Designer
Executive Summary
The Hong Kong-Zhuhai-Macao Bridge (HZMB) Hong
Kong Link Road (HKLR) serves to connect the HZMB Main Bridge at the Hong Kong
Special Administrative Region (HKSAR) Boundary and the HZMB Hong Kong Boundary
Crossing Facilities (HKBCF) located at the north eastern waters of the Hong
Kong International Airport (HKIA).
The HKLR project has been separated into two
contracts. They are Contract No.
HY/2011/03 Hong Kong-Zhuhai-Macao Bridge Hong Kong Link Road-Section between
Scenic Hill and Hong Kong Boundary Crossing Facilities (hereafter referred to
as the Contract) and Contract No. HY/2011/09 Hong Kong-Zhuhai-Macao Bridge Hong
Kong Link Road-Section between HKSAR Boundary and Scenic Hill.
China State Construction Engineering (Hong Kong)
Ltd. was awarded by Highways Department as the Contractor to undertake the
construction works of Contract No. HY/2011/03. The main works of the Contract include
land tunnel at Scenic Hill, tunnel underneath Airport Road and Airport Express
Line, reclamation and tunnel to the east coast of the Airport Island, at-grade
road connecting to the HKBCF and highway works of the HKBCF within the Airport
Island and in the vicinity of the HKLR reclamation. The Contract is part of the HKLR Project
and HKBCF Project, these projects are considered to be ¡§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/H for
HKBCF were issued on 22 December 2014 and 19 January 2015, respectively. These
documents are available through the EIA Ordinance Register. The construction
phase of Contract was commenced on 17 October 2012.
BMT Asia Pacific Limited has been appointed by
the Contractor to implement the Environmental Monitoring & Audit (EM&A)
programme for the Contract in accordance with the Updated EM&A Manual for
HKLR (Version 1.0) and will be providing environmental team services to the
Contract.
This is the tenth Quarterly EM&A report for
the Contract which summaries the monitoring results and audit findings of the
EM&A programme during the reporting period from 1 December 2014 to 28 February 2015.
Environmental
Monitoring and Audit Progress
The EM&A programme
were undertaken in accordance with the Updated EM&A Manual for HKLR
(Version 1.0). A summary of the
monitoring activities during this reporting period is presented as below:
Monitoring Activity
|
Monitoring Date
|
December 2014
|
January 2015
|
February
2015
|
Air
Quality
|
1-hr TSP
|
1, 5, 11,
17, 23 and 29
|
2, 6, 12,
16, 22 and 28
|
3, 9, 13,
18 and 24
|
24-hr TSP
|
AMS5: 2,
5, 17, 22, 24 and 30
AMS6: 4,
10, 16, 22, 24 and 30
|
5, 9, 15,
21 and 27
|
2, 6, 12,
17, 23 and 27
|
Noise
|
1, 11,
17, 23 and 29
|
6, 16, 22
and 28
|
3, 9, 18
and 24
|
Water
Quality
|
1, 3, 5,
8, 10, 12, 15, 17, 19, 22, 24, 26, 29 and 31
|
2, 5, 7,
9, 12, 14, 16, 19, 21, 23, 26, 28 and 30
|
2, 4, 6,
9, 11, 13, 16, 18, 20, 23, 25 and 27
|
Chinese
White Dolphin
|
2, 9, 15
and 23
|
8, 15, 27
and 29
|
5, 13, 16
and 25
|
Mudflat
Monitoring (Ecology)
|
6, 7, 10,
21, 22 and 23
|
-
|
-
|
Mudflat
Monitoring (Sedimentation rate)
|
13
|
-
|
-
|
Site Inspection
|
3, 10,
17, 24 and 30
|
7, 14, 21
and 30
|
4, 11, 17
and 27
|
Due to malfunction of
HVS at AMS5 on 28 November 2014, the 24-hr TSP monitoring undertaken at AMS5
was less than 24 hours and the result was therefore considered invalid. The
24-hr TSP monitoring was rescheduled from 28 November 2014 to 2 December 2014. The monitoring result for
2 December 2014 is provided in this report.
Due to power
interruption of HVS at station AMS5, the 24-hr TSP monitoring at station AMS5 was rescheduled from 4 December 2014 to 5 December 2014.
Due to malfunction of
HVS at station AMS5, the 24-hr TSP monitoring at station AMS5 on 10 December
2014 was cancelled. The 24-hr
TSP monitoring at station AMS5 was rescheduled to 17 December 2014 after repairing the HVS.
Due to the change of tide pattern and weather condition, mudflat
monitoring (ecology) was rescheduled from 20 December 2014 to 10 December 2014.
Due to bad weather
condition on 12 January 2015, the noise monitoring at station NMS5 was rescheduled from 12 January 2015 to 16 January 2015.
Due to boat
availability issue, the dolphins monitoring was rescheduled from 3 December
2014 to 2 December 2014, 22 December 2014 to 23 December 2014, 6 January 2015
to 8 January 2015, 20 January 2015 to 29 January 2015 and 12 February 2015 to
13 February 2015.
Breaches
of Action and Limit Levels
A summary of environmental exceedances for this
reporting period is as follows:
Environmental Monitoring
|
Parameters
|
Action Level (AL)
|
Limit Level (LL)
|
Air
Quality
|
1-hr TSP
|
0
|
0
|
24-hr TSP
|
3
|
0
|
Noise
|
Leq
(30 min)
|
0
|
0
|
Water
Quality
|
Suspended
solids level (SS)
|
5
|
2
|
Turbidity
level
|
0
|
0
|
Dissolved
oxygen level (DO)
|
0
|
0
|
Dolphin
Monitoring
|
Quarterly
Analysis (Dec 14 to Feb 2015)
|
0
|
1
|
The Environmental Team investigated all
exceedances and found that they were not project related.
All investigation reports for exceedances of the
Contract have been submitted to ENPO/IEC for comments and/or follow up to
identify whether the exceedances occurred related to other HZMB contracts.
Implementation of Mitigation Measures
Site inspections were carried out on a weekly
basis to monitor the implementation of proper environmental pollution control
and mitigation measures for the Project.
Potential environmental impacts due to the construction activities were
monitored and reviewed.
Complaint Log
There were two environmental complaints received
in relation to the environmental impact during the reporting period.
A summary of environmental complaints for this
reporting period is as follows:
Environmental Complaint No.
|
Date of Complaint Received
|
Description of Environmental Complaints
|
COM-2014-063
|
3
December 2014
|
Noise
|
COM-2014-065
|
24
December 2014
|
Water
Quality
|
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.
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/H for HKBCF were issued on 22 December
2014 and 19 January 2015, respectively. These documents are available through
the EIA Ordinance Register. The construction
phase of Contract was commenced on 17 October
2012. Figure 1.1 shows the project site boundary.
1.1.5
This is the tenth Quarterly Environmental Monitoring and
Audit (EM&A) report for the Contract which summaries the monitoring results
and audit findings of the EM&A programme during the reporting period from 1
December 2014 to 28 February 2015.
1.2.1 The project organization structure and lines of
communication with respect to the on-site environmental management structure
with the key personnel contact names and numbers are shown in Appendix A.
1.3
Construction
Programme
1.3.1
A copy of the 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
Site Area
|
Description of Activities
|
Portion X
|
¡P
Dismantling/trimming of temporary 40mm
stone platform for construction of seawall
¡P
Filling works behind stone platform
¡P
Temporary stone platform construction
¡P
Sheet piling
¡P
Excavation and lateral support works for
Scenic Hill Tunnel (Cut & Cover Tunnel)
¡P
Construction of seawall
|
Portion Y
|
¡P
Access shaft construction for Scenic Hill
Tunnel& HKBCF to Airport Tunnel
¡P
Utility culvert excavation
¡P
Highway Operation and Maintenance Area
Building Foundation Works
|
West Portal
|
¡P
Pipe roofing installation and excavation
for Scenic Hill Tunnel
¡P
Ventilation Building Foundation Works
|
Airport Express Line
|
¡P
Pre-grouting and pipe piling works for Airport
Express Line access shafts
|
Airport Road
|
¡P
Excavation works for HKBCF to Airport
Tunnel West (Cut & Cover Tunnel)
¡P
Pipe Piling Cofferdam Works for HKBCF to Airport Tunnel West (Cut
& Cover Tunnel)
|
Kwo Lo Wan /Airport Road
|
¡P
Works for diversion of Airport Road and Kwo
Lo Wan Road
|
Kwo Lo Wan /Airport Road /Airport
Express Line
|
¡P
Utilities detection
|
Kwo Lo Wan Road
|
¡P
Excavation and lateral support works at
shaft 3 extension north shaft & south shaft
|
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
trigger 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
trigger 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 carried out corrective actions.
Details of site audit findings and the corrective actions during the
reporting period are presented in Appendix
F.
3.1.2
A summary of the Implementation Schedule of
Environmental Mitigation Measures (EMIS) is presented in Appendix E.
3.1.3
Regular marine travel route for
marine vessels were implemented properly in accordance to the submitted plan
and relevant records were kept properly.
3.1.4
Dolphin Watching Plan was
implemented during the reporting period.
No dolphins inside the silt curtain were observed. The relevant records were
kept properly.
3.2.1
The monitoring results for 1-hour TSP and
24-hour TSP are summarized in Tables 3.1 and 3.2
respectively. Detailed impact air quality monitoring results and relevant graphical
plots are presented in Appendix G.
Table 3.1 Summary
of 1-hour TSP Monitoring Results During the Reporting Period
Reporting Period
|
Monitoring
Station
|
Average (mg/m3)
|
Range (mg/m3)
|
Action Level (mg/m3)
|
Limit Level (mg/m3)
|
December 2014
|
AMS5
|
140
|
76 - 276
|
352
|
500
|
AMS6
|
131
|
72 - 239
|
360
|
January 2015
|
AMS5
|
139
|
86 - 229
|
352
|
AMS6
|
136
|
67 - 207
|
360
|
February 2015
|
AMS5
|
180
|
107 - 283
|
352
|
AMS6
|
175
|
107 - 245
|
360
|
Table 3.2 Summary
of 24-hour TSP Monitoring Results During the Reporting Period
Reporting Period
|
Monitoring
Station
|
Average (mg/m3)
|
Range (mg/m3)
|
Action Level (mg/m3)
|
Limit Level (mg/m3)
|
December 2014
|
AMS5
|
78
|
56-107
|
164
|
260
|
AMS6
|
130
|
40-218
|
173
|
January 2015
|
AMS5
|
97
|
56- 189
|
164
|
AMS6
|
123
|
76 - 212
|
173
|
February 2015
|
AMS5
|
81
|
36 - 132
|
164
|
AMS6
|
86
|
46 - 144
|
173
|
3.2.2 No Action and Limit Level
exceedances of 1-hour TSP and no Limit Level exceedance of 24-hour TSP were
recorded at AMS5 and AMS6 during the reporting period.
3.2.3 An Action Level exceedance
of 24-hour TSP at AMS5 was recorded on 21 January 2015. An Action Level
exceedance of 24-hour TSP at AMS6 was recorded on 16 December 2014 and 21 January 2015,
respectively.
3.3
Noise Monitoring Results
3.3.1
The monitoring results for construction noise
are summarized in Table 3.3 and the
monitoring results and relevant graphical plots for this reporting
period are provided in Appendix H.
Table 3.3 Summary
of Construction Noise Monitoring Results During the Reporting Period
Reporting period
|
Monitoring
Station
|
Average Leq
(30 mins), dB(A)*
|
Range of Leq
(30 mins), dB(A)*
|
Action Level
|
Limit Level Leq
(30 mins), dB(A)
|
December 2014
|
NMS5
|
60
|
58 ¡V 62
|
When one documented complaint is received
|
75
|
January 2015
|
58
|
56 ¡V 61
|
February 2015
|
59
|
57 ¡V 60
|
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.
3.4.1
Impact water quality monitoring was conducted at
all designated monitoring stations during the reporting period. Impact water quality monitoring results and
relevant graphical plots are provided in
Appendix I.
3.4.2
During the reporting period, five Action
Level exceedances and two Limit Level exceedances for
suspended solid level were recorded. No exceedances of Action and Limit Level for
dissolved oxygen level and turbidity were recorded.
3.4.3
Water quality impact sources during the water
quality monitoring were the construction activities of the Contract, nearby
construction activities by other parties and nearby operating vessels by other
parties.
Data
Analysis
3.5.1
Distribution Analysis ¡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 entire
quarterly period (December 2014 ¡V February 2015).
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 December 2014 to
February 2015, six sets of systematic line-transect vessel surveys were
conducted to cover all transect lines in NWL and NEL survey areas twice per month.
3.5.10
From these surveys, a total of 891.50 km
of survey effort was collected, with 99.6% 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, 347.05 km and 544.45 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 645.44 km, while the effort on secondary lines was 246.06
km. Both survey effort conducted on
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 December 2014 to February 2015, a total of 15 groups of 52 Chinese White
Dolphins were sighted. All dolphin
sightings were made during on-effort search. Twelve of the 15 on-effort sightings
were made on primary lines, while the other three were made on secondary
lines. In this quarterly period,
all dolphin groups were sighted in NWL, while none of them were sighted in
NEL. A summary table of the dolphin
sightings is shown in Annex II of Appendix J.
Distribution
3.5.13
Distribution of dolphin sightings made
during monitoring surveys in December 2014 to February 2015 is shown in Figure 1 of
Appendix J.
Similar to recent quarters, the majority of dolphin sightings made in the
present quarter were concentrated in the northwestern end of the North Lantau region, with higher concentration near the
northern boundary of the survey area and around Lung Kwu Chau (Figure 1 of Appendix J). Similar to recent quarters, the majority
of dolphin sightings made in the present quarter were concentrated in the
northwestern end of the North Lantau region,
with higher concentration near the northern boundary of the survey area and
around Lung Kwu Chau.
3.5.14
Notably, all dolphin sightings were made
far away from the HKLR03/HKBCF reclamation sites or along the entire alignment
of HKLR09 and Tuen Mun-Chek Lap Kok Link (TMCLKL) during this quarterly period (Figure 1 of Appendix J).
3.5.15
Sighting distribution of the present
impact phase monitoring period (December 2015 to February 2015) was compared to
the one during the baseline monitoring period (September to November
2011). In the present quarter,
dolphins have completely avoided the NEL region, which was in stark contrast to
their frequent occurrence around the Brothers
Islands and in the
vicinity of HKBCF reclamation site during the baseline period (Figure 1 of Appendix J). The nearly complete abandonment of NEL region by the
dolphins has been consistently recorded in the past eight quarters, which have
resulted in extremely low to zero dolphin encounter rate in this area.
3.5.16
In NWL survey area, dolphin occurrence was
also drastically different between the baseline and impact phase quarters. During the present impact monitoring
period, much fewer dolphins occurred in the middle portion of North Lantau
region than those during the baseline period, where dolphins supposedly moved between
their core areas around Lung Kwu Chau and the Brothers Islands (Figure 1 of Appendix J). Moreover,
more dolphins were sighted near Sha Chau and Black Point during the baseline
period than those during the present impact monitoring period (Figure 1 of Appendix
J). During the baseline period,
a number of dolphin groups were sighted to the west of Chek Lap Kok airport
(especially near the HKLR09 alignment) during the baseline period, while they
have disappeared from this area during the present impact phase period.
3.5.17
Another comparison in dolphin distribution
was made between the three quarterly periods of winter months in 2012-13,
2013-14 and 2014-15 (Figure 2 of Appendix
J). Among the three winter
periods, no dolphin sighting was made in NEL in 2014-15, while there were two
sightings made there in 2013-14, and eight sightings in 2012-13 (Figure 2 of Appendix
J). This clearly indicated a
progressive decline in dolphin usage in NEL waters in the past few years.
3.5.18
Moreover, dolphins regularly occurred in
the middle and western portions of North Lantau waters (especially between
Black Point and Lung Kwu Chau, as well as around Sha Chau) during the winter of
2012-13, but such usage has also progressively diminished in 2013-14 and
2014-15 (Figure 2 of Appendix
J). The temporal trend
indicated that dolphin usage in the overall North Lantau
region has greatly diminished during the winter months of the past few years.
Encounter Rate
3.5.19
During the present three-month
study period, the encounter rates of Chinese White Dolphins deduced from the
survey effort and on-effort sighting data from the primary transect lines under
favourable conditions (Beaufort 3 or below) for each set of the surveys in NEL
and NWL are shown in Table 3.4.
The average encounter rates deduced from the six
sets of surveys were also compared with the ones deduced from the baseline
monitoring period (September ¡V November 2011) (See Table
3.5).
Table
3.4 Dolphin
Encounter Rates (Sightings Per 100 km of Survey Effort) During Reporting Period
(Dec 2014 ¡V Feb 2015)
Survey Area
|
Dolphin Monitoring
|
Encounter rate (STG)
(no. of on-effort dolphin sightings per 100 km of survey effort)
|
Encounter rate (ANI)
(no. of dolphins from all on-effort sightings per 100 km of survey effort)
|
Primary Lines Only
|
Primary Lines Only
|
Northeast Lantau
|
Set 1 (2 & 9 Dec
2014)
|
0.00
|
0.00
|
Set 2 (15 & 22 Dec
2014)
|
0.00
|
0.00
|
Set 3 (8 & 15 Jan 2015)
|
0.00
|
0.00
|
Set 4 (27 & 29 Jan 2015)
|
0.00
|
0.00
|
Set 5 (5 & 13 Feb 2015)
|
0.00
|
0.00
|
Set 6 (16 & 25 Feb 2015)
|
0.00
|
0.00
|
Northwest Lantau
|
Set 1 (2 & 9 Dec
2014)
|
2.79
|
5.58
|
Set 2 (15 & 22 Dec
2014)
|
1.41
|
1.41
|
Set 3 (8 & 15 Jan 2015)
|
4.33
|
21.64
|
Set 4 (27 & 29 Jan 2015)
|
7.52
|
37.59
|
Set 5 (5 & 13 Feb 2015)
|
1.40
|
1.40
|
Set 6 (16 & 25 Feb 2015)
|
0.00
|
0.00
|
Table
3.5 Comparison
of average dolphin encounter rates from impact monitoring period (December 2014
¡V February 2015) 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
|
0.00
|
6.00 ¡Ó 5.05
|
0.00
|
22.19 ¡Ó 26.81
|
Northwest Lantau
|
2.91 ¡Ó 2.69
|
9.85 ¡Ó 5.85
|
11.27 ¡Ó 15.19
|
44.66 ¡Ó 29.85
|
Note:
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
3.5.20
To facilitate the comparison with the AFCD long-term monitoring results,
the encounter rates were also calculated for the present quarter using both
primary and secondary survey effort.
The encounter rates of sightings (STG) and dolphins (ANI) in NWL were
2.77 sightings and 9.62 dolphins per 100 km of survey effort respectively,
while the encounter rates of sightings (STG) and dolphins (ANI) in NEL were
both nil.
3.5.21
In NEL, the average dolphin
encounter rates (both STG and ANI) in the present three-month impact monitoring
period were zero, and such low occurrence of dolphins in NEL have been
consistently recorded in the past eight quarters (Table 3.6). It is a serious
concern that dolphin occurrence in NEL in the eight quarters (0.0-1.0 for
ER(STG) and 0.0-3.9 for ER(ANI)) have been exceptionally low when compared to
the baseline period (Table 3.6). Dolphins have almost vacated from NEL
waters since January 2014, with only one
group of four dolphins sighted since then.
3.5.22
Moreover, the average dolphin encounter rates (STG and ANI) in NWL
during the present impact phase monitoring period were also much lower
(reductions of 70.5% and 74.8% respectively) than the ones recorded in the
3-month baseline period, indicating a dramatic decline in dolphin usage of this
survey area during the present impact phase period (Table 3.7).
Table
3.6 Comparison of Average
Dolphin Encounter Rates in Northeast Lantau Survey Area from All Quarters of
Impact Monitoring Period and Baseline Monitoring Period (Sep ¡V Nov 2011)
|
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
|
Note:
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.
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)
|
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
|
Note: 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.
3.5.23
Notably, the last eighth consecutive quarters
have triggered the Action Levels under the Event and Action Plan, while the
current quarter has triggered the Limit Level. As discussed recently in Hung (2014),
the dramatic decline in dolphin usage of NEL waters in 2012 and 2013 (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 in 2012. It appeared that such noticeable decline
has already extended to NWL waters progressively in 2013 and 2014.
3.5.24
A two-way ANOVA with repeated measures and
unequal sample size was conducted to examine whether there were any significant
differences in the average encounter rates between the baseline and impact
monitoring periods. The two
variables that were examined included the two periods (baseline and impact
phases) and two locations (NEL and NWL).
3.5.25
For the comparison between the baseline period
and the present quarter (ninth quarter of the impact phase being assessed), the
p-value for the differences in average dolphin encounter rates of STG and ANI
were 0.0059 and 0.0330 respectively.
If the alpha value is set at 0.05, significant difference was detected
between the baseline and present quarters in both dolphin encounter rates of
STG and ANI.
3.5.26
For the comparison between the baseline period
and the cumulative quarters in impact phase (i.e. first eight quarters of the
impact phase being assessed), the p-value for the differences in average
dolphin encounter rates of STG and ANI were 0.0009 and 0.0003
respectively. Even if the alpha
value is set at 0.01, significant differences were detected in both the average
dolphin encounter rates of STG and ANI (i.e. between the two periods and the
locations).
3.5.27
As indicated in both dolphin distribution
patterns and encounter rates, dolphin usage has been significantly reduced in
NEL and NWL waters in the present quarterly period, and such low occurrence has
been consistently documented in previous quarters. This raises serious concern, as the
decline in dolphin usage in North Lantau waters could possibly link to the HZMB-related
construction activities.
3.5.28
To ensure the continuous usage of North Lantau waters by the dolphins, every possible
measure should be implemented by the contractors and relevant authorities to
minimize all disturbances to the dolphins.
Group
Size
3.5.29
Group size of Chinese White Dolphins ranged from
one to eight individuals per group in North Lantau region during December 2014 to
February 2015. The average dolphin
group sizes from these three months were compared with the ones deduced from
the baseline period in September to November 2011, as shown in Table 3.8.
Table 3.8 Comparison
of Average Dolphin Group Sizes between Reporting Period (December 2014 ¡V
February 2015) and Baseline Monitoring Period (Sep¡V Nov 2011)
|
Average Dolphin Group Size
|
Reporting Period
|
Baseline Monitoring Period
|
Overall
|
3.47 ¡Ó 2.29 (n = 15)
|
3.72 ¡Ó 3.13 (n
= 66)
|
Northeast Lantau
|
0.00
|
3.18 ¡Ó 2.16 (n
= 17)
|
Northwest Lantau
|
3.47 ¡Ó 2.29 (n =
15)
|
3.92 ¡Ó 3.40 (n
= 49)
|
3.5.30
The average dolphin group sizes in NWL waters during December 2014 to
February 2015 were slightly smaller than the ones recorded during the three-month
baseline period (Table 3.8). Ten of the 15 groups were composed of
1-4 individuals only, while none of the dolphin group had more than 10
individuals.
3.5.31
Distribution of dolphins with larger group sizes (five individuals or
more per group) during the present quarter is shown in Figure 3 of Appendix J, with comparison to the one in baseline
period. During the winter of
2014-15, distribution of the few dolphin groups were concentrated near Lung Kwu
Chau (Figure 3 of Appendix J). This
distribution pattern was very different from the baseline period, when the
larger dolphin groups were distributed more evenly in NWL waters with a few
more sighted in NEL waters (Figure 3 of
Appendix J).
3.5.32
Notably, none of the larger dolphin groups were sighted near the HKLR03
reclamation site in the present monitoring period (Figure 3 of Appendix J).
Habitat Use
3.5.33
From December 2014 to February 2015, the most heavily utilized habitats
by Chinese White Dolphins mainly concentrated around Lung Kwu Chau and the
northern end of NWL survey area (Figures
4a and 4b of Appendix J). None of the grids in NEL recorded the
presence of dolphins in the present quarter. Moreover, all grids near HKLR03/HKBCF
reclamation sites, HKLR09 or TMCLKL alignment did not record any presence of
dolphins during on-effort search in the present quarterly period.
3.5.34
However, it should be emphasized that the amount of survey effort
collected in each grid during the three-month period was fairly low (6-12 units
of survey effort for most grids), and therefore the habitat use pattern derived
from the three-month dataset should be treated with caution. A more complete picture of dolphin
habitat use pattern will be presented when more survey effort for each grid
will be collected throughout the impact phase monitoring programme.
3.5.35
When compared with the habitat use patterns during the baseline period,
dolphin usage in NEL and NWL was dramatically different from the present impact
monitoring period (Figure 5 of Appendix J). During the baseline
period, nine grids between Siu Mo To and Shum Shui Kok recorded moderately high
to high dolphin densities, which was in stark contrast to complete absence of
dolphins during the present impact phase period (Figure 5 of Appendix J).
3.5.36
The density patterns between the baseline and impact phase monitoring
periods were also very different in NWL, with higher dolphin usage around Sha
Chau, near Black Point, to the west of the airport, as well as between Pillar
Point and airport platform during the baseline period (Figure 5 of Appendix J). During the present impact phase period,
the dolphin usage was confined to the northwestern end of the survey area
around Lung Kwu Chau.
Mother-calf Pairs
3.5.37
During the present quarterly period, no young calves (i.e. unspotted
calves or unspotted juveniles) for the first time among the ten quarters of
impact phase monitoring. This
absence of young calves is also in stark contrast to their regular occurrence
during the baseline period. Their
absences should be of a serious concern, and the occurrence of calves should be
closely monitored in the upcoming quarters.
Activities
and Associations with Fishing Boats
3.5.38
Only one dolphin sighting each was associated with feeding and
socializing activities respectively during the three-month study period. The percentage of sightings associated
with feeding activities during the present quarter (6.7%) was much lower than
the one recorded during the baseline period (11.6%). On the other hand, the percentage of
socializing activities during the present impact phase monitoring period (6.6%)
was slightly higher than the one recorded during the baseline period (5.4%). None of the 15 dolphin groups were
engaged in traveling or milling/resting behaviour.
3.5.39
Distribution of dolphins engaged in feeding and socializing activities
during the present three-month period is shown in Figure 6 of Appendix J. The lone sightings associated with
feeding and socializing activities were located to the north of the airport and
near Lung Kwu Chau respectively (Figure
6 of Appendix J). Distribution of dolphin sightings
associated with these activities during the impact phase was very different
from the distribution pattern of these activities during the baseline period (Figure 6 of Appendix J).
3.5.40
As in the past monitoring quarters, none of the 15 dolphin groups was
found to be associated with an operating fishing vessel in North
Lantau waters during the present impact phase period. The extremely rare events of fishing
boat association in the present and previous quarters were consistently found,
and were likely related to the recent trawl ban being implemented in December
2012 in Hong Kong waters.
Photo-identification
and Individual Range Use
3.5.41
From December 2014 to February 2015, over 1,500 digital photographs of
Chinese White Dolphins were taken during the impact phase monitoring surveys
for the photo-identification work.
3.5.42
In total, 24 individuals sighted 32 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 32
re-sightings were made in NWL.
3.5.43
The majority of identified individuals were sighted only once or twice during
the three-month period, with the exception of one individual (CH34) being
sighted thrice.
3.5.44
Two of these 24 individuals (NL259 and NL285) were also sighted in West
Lantau waters during the HKLR09 monitoring surveys for the same three-month
period, showing their extensive movement between North and West Lantau regions.
Five recognized females (NL98, NL104, NL123, NL202 and WL17) were
accompanied with calves during their re-sightings. Some of these mothers were
frequently sighted with their calves throughout the HKLR03 impact phase
monitoring period since October 2012. Individual range use
3.5.45
Ranging patterns of the 24 individuals identified during the three-month
study period were determined by fixed kernel method, and are shown in Annex V of Appendix J.
3.5.46
All identified dolphins sighted in this quarter were utilizing their
range use in NWL, but have avoided the NEL waters where many of them have
utilized as their core areas in the past (Annex V of Appendix J). This is in contrary to
the extensive movements between NEL and NWL survey areas observed in the
earlier impact monitoring quarters as well as during the baseline period.
3.5.47
Notably, two individuals (NL259 and NL285) sighted in NWL and NEL waters
consistently in the past have extended their range use to WL waters in the
present quarter. It should be
further monitored to examine whether there has been any consistent shifts of
home ranges of individuals from North Lantau
to West Lantau, which could also possibly be
related to the HZMB-related construction works.
Action
Level / Limit Level Exceedance
3.5.48
There was one Limit Level exceedance of dolphin monitoring for the
quarterly monitoring data (December 2014 ¡V February 2015). According to the contractor¡¦s information, the
marine activities undertaken for HKLR03 during the quarter of December 2014 to
February 2015 included reclamation, excavation of stone platform, surcharge
activities, construction of seawall, temporary drainage diversion and ground
investigation. There is no evidence showing the current Limit Level
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
October 2012. It should also be noted that reclamation work under HKLR03
(adjoining the Airport Island) situates in waters which has rarely been used by
dolphins in the past, and the working vessels under HKLR03 have been travelling
from source to destination in accordance with the Marine Travel Route to
minimize impacts on Chinese White Dolphin.
In addition, the contractor will implement proactive mitigation measures
such as avoiding anchoring at Marine Department¡¦s designated anchorage site ¡V
Sham Shui Kok Anchorage (near Brothers Island) as far as practicable.
3.5.49
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).
3.5.50
For the comparison between the baseline period and the present quarter
(ninth quarter of the impact phase), the p-value for the differences in average
dolphin encounter rates of STG and ANI were 0.0059 and 0.0330
respectively. If the alpha value is
set at 0.05, significant difference was detected between the baseline and
present quarters in both encounter rates of STG and ANI.
3.5.51
For the comparison between the baseline period and the cumulative
quarters in impact phase (i.e. first nine quarters of the impact phase), the
p-value for the differences in average dolphin encounter rates of STG and ANI
were 0.0009 and 0.0003 respectively.
Even if the alpha value is set at 0.01, significant difference was
detected in both the average dolphin encounter rates of STG and ANI (i.e.
between the two periods and the locations).
3.5.52
The AFCD monitoring data during December 2014 to February 2015 has been
reviewed by the dolphin specialist, and no dolphin was sighted from 103.64 km
of survey effort on primary lines in NEL during the same quarter. This review has confirmed that the
extremely low occurrence of dolphins reported by the HKLR03 monitoring survey
in winter 2014-15 in NEL is accurate.
3.5.53
There is no evidence showing that the sources of impact directly related
to the construction works of HKLR03 that may have affected the dolphin usage in
the NEL region.
3.5.54
All dolphin protective measures are fully and properly implemented in
accordance with the EM&A Manual. According to the Marine Travel Route Plan,
if vessels are crossing along edge of the proposed marine park, the travelling
speed will keep not exceeding 5 knots when crossing the edge of the proposed marine
park. The Contractor will continue to provide training for skippers to ensure
that their working vessels travel from source to destination to minimize
impacts on Chinese White Dolphin and avoid anchoring at Marine 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.
3.5.55
A
meeting was held on 27 April 2015 with attendance of ENPO, Resident Site Staff
(RSS), Environmental Team (ET) and dolphin specialist for Contract No.
HY/2010/02, RSS, ET, dolphin specialist and main Contractor for Contract No.
HY/2011/03. The discussion/recommendation as recorded in the minutes of the
meeting, which might be relevant to HKLR03 Contract are summarized below.
3.5.56
It
was concluded that the HZMB works is one of the contributing factors affecting
the dolphins. It was also concluded the contribution of impacts due to the HZMB
works as a whole (or individual marine contracts) cannot be quantified nor
separate from the other stress factors.
3.5.57
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.
3.5.58
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.
3.5.59
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.
3.5.60
It
was suggested that the protection measures (e.g., speed limit control) for the
proposed Brothers Island Marine Park (BMP) shall be brought forward as soon as
possible before its establishment so as to provide a better habitat for dolphin
recovery. It was noted that under the Regular Marine Travel Route Plan, the
contractors have committed to reduce the vessel speed in BMP.
3.5.61
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 13 December
2014. The mudflat surface levels at
the four established monitoring stations and the corresponding XYZ HK1980 GRID
coordinates are presented in Table 3.8 and Table 3.9.
Table 3.8 Measured
Mudflat Surface Level Results
|
Baseline Monitoring
(September 2012)
|
Impact Monitoring
(December 2014)
|
Monitoring Station
|
Easting (m)
|
Northing (m)
|
Surface Level
|
Easting (m)
|
Northing (m)
|
Surface Level
|
(mPD)
|
(mPD)
|
S1
|
810291.160
|
816678.727
|
0.950
|
810291.034
|
816678.685
|
1.050
|
S2
|
810958.272
|
815831.531
|
0.864
|
810958.223
|
815831.493
|
0.915
|
S3
|
810716.585
|
815953.308
|
1.341
|
810716.537
|
815953.273
|
1.469
|
S4
|
811221.433
|
816151.381
|
0.931
|
811221.458
|
816151.337
|
1.055
|
Table 3.9 Comparison
of measurement
|
Comparison of measurement
|
Remarks and Recommendation
|
Monitoring Station
|
Easting (m)
|
Northing (m)
|
Surface Level
(mPD)
|
S1
|
-0.126
|
-0.042
|
0.100
|
Level continuously increased
|
S2
|
-0.049
|
-0.038
|
0.051
|
Level continuously increased
|
S3
|
-0.048
|
-0.032
|
0.128
|
Level continuously increased
|
S4
|
0.025
|
-0.044
|
0.124
|
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
December
2014. 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 3.10 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)
|
01-Dec-14
|
6.49
|
3.00
|
5.95
|
6.93
|
8.70
|
10.80
|
03-Dec-14
|
6.67
|
4.85
|
6.80
|
6.80
|
9.70
|
11.25
|
05-Dec-14
|
6.70
|
5.80
|
11.15
|
7.08
|
6.10
|
11.40
|
08-Dec-14
|
7.25
|
4.65
|
5.20
|
7.16
|
4.40
|
5.40
|
10-Dec-14
|
7.43
|
3.80
|
4.60
|
7.40
|
2.75
|
3.30
|
12-Dec-14
|
7.93
|
2.05
|
4.75
|
7.67
|
3.10
|
5.20
|
15-Dec-14
|
8.65
|
1.55
|
1.60
|
8.45
|
3.05
|
3.90
|
17-Dec-14
|
8.46
|
2.60
|
2.35
|
9.29
|
2.75
|
3.20
|
19-Dec-14
|
8.76
|
0.70
|
2.55
|
8.88
|
0.50
|
2.30
|
22-Dec-14
|
8.93
|
1.80
|
2.10
|
8.82
|
1.35
|
3.75
|
24-Dec-14
|
8.63
|
2.50
|
2.40
|
8.60
|
1.45
|
2.50
|
26-Dec-14
|
8.49
|
1.25
|
2.85
|
8.65
|
1.60
|
3.65
|
29-Dec-14
|
7.77
|
1.70
|
3.75
|
8.01
|
1.55
|
7.70
|
31-Dec-14
|
8.18
|
1.35
|
2.30
|
8.44
|
0.95
|
3.35
|
Average
|
7.88
|
2.69
|
4.17
|
8.01
|
3.43
|
5.55
|
Mudflat Ecology Monitoring
Sampling
Zone
3.6.6
There are two survey areas specified under the
updated EM&A Manual for the Contract, namely Tung Chung Bay and San
Tau. Tung Chung Bay survey area is
divided into three sampling zones (TC1, TC2 and TC3) and there is one sampling
zone at San Tau (ST). Survey of
horseshoe crabs, seagrass beds and intertidal communities were conducted in
each sampling zone. The present survey was conducted in December 2014 (totally 6 sampling days between 6th and 23rd December 2014).
The locations of sampling zones are shown in Annex I of Appendix O.
Horseshoe
Crabs
3.6.7
Active search method was conducted for
horseshoe crab monitoring by two experienced surveyors at every sampling
zone. During the search period, any accessible and
potential area would be investigated for any horseshoe crab individuals within
2-3 hours in low tide period (tidal level
below 1.2 m above Chart Datum (C.D.)). Once a horseshoe crab individual was found, the
species was identified referencing to Li (2008). The prosomal
width, inhabiting substratum and respective
GPS coordinate were recorded. A photographic
record was taken for
future investigation. Any
grouping behavior of individuals, if found, was recorded. The horseshoe crab surveys were conducted on 10th (for TC1
and TC2) and 23rd (for TC3 and ST) December 2014. The weather was
cloudy on both survey days.
Seagrass Beds
3.6.8
Active search method was conducted for seagrass
bed monitoring by two
experienced surveyors at every sampling zone. During the search
period, any accessible and potential area would be investigated for any
seagrass beds within 2-3 hours in low tide period. Once
seagrass bed was found, the species, estimated area, estimated coverage percentage and respective GPS coordinate were
recorded. A photographic record was taken for future investigation. The seagrass beds surveys were conducted on 10th (for TC1
and TC2) and 23rd (for TC3 and ST) December 2014.
Intertidal Soft Shore
Communities
3.6.9 The intertidal soft shore
community surveys were conducted in low tide period on 6th (for
TC1), 7th (for TC2), 21st (for TC3) and 22nd
December 2014 (for ST). At each sampling zone, three 100 m horizontal transects were laid at high
tidal level (H: 2.0 m above C.D.), mid tidal level (M: 1.5 m above C.D.) and low
tidal level (L: 1.0 m above C.D.). Along every horizontal transect, ten random quadrats
(0.5 m x 0.5m) were placed.
3.6.10
Inside a quadrat, any visible epifauna were collected
and were in-situ identified to the
lowest practical taxonomical resolution. Whenever possible a hand core sample (10 cm internal diameter ´ 20 cm depth) of sediments was collected in the quadrat. The core sample was gently washed through a sieve of mesh size 2.0 mm in-situ. Any visible
infauna were collected and identified. Finally the top 5 cm surface sediments
was dug for visible infauna in the quadrat regardless of hand core sample was
taken.
3.6.11
All collected fauna were
released after recording except some tiny individuals that are too small to be identified on site. These
tiny individuals were taken to laboratory for identification under dissecting microscope.
3.6.12
The taxonomic classification
was conducted in accordance to the following references: Polychaetes: Fauchald (1977), Yang and Sun (1988); Arthropods: Dai and Yang (1991), Dong (1991);
Mollusks: Chan and Caley (2003), Qi (2004).
Data
Analysis
3.6.13
Data collected from direct search and core
sampling was pooled in every quadrat for data analysis. Shannon-Weaver
Diversity Index (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
3.6.14
Table 3.1 and Figure 3.1 of Appendix O shows the records of horseshoe crab survey at every sampling zone. Two individuals of Carcinoscorpius rotundicauda was found in TC1 only. Few individuals of Tachypleus tridentatus were found in sampling zones TC3 (3 ind.) and ST (5 ind.). All individuals were found on fine sand or soft mud substrata. Every sight record consisted of
single individual that no grouping behaviour was observed.
3.6.15
Table 3.2 of
Appendix O summarizes the survey results of
horseshoe crab at every sampling zone. For Carcinoscorpius rotundicauda, the search records were 0.5 ind. hr-1
person-1 (mean prosomal width: 41.53 mm), in TC1. According to Li (2008), the prosomal width of recorded individuals ranged 32.13¡Ð50.92 mm that was about 5.3-8.2 years
old. For
Tachypleus tridentatus, the search record was 0.8 ind. hr-1 person-1 (46.86 mm) and 1.3 ind. hr-1 person-1 (64.03 mm) in TC3 and ST
respectively. The
prosomal
width of recorded individuals ranged
37.27¡Ð72.40 mm that was about 4.6¡V8.5 years old.
3.6.16
No marked individual of horseshoe crab was recorded
in present survey. Some marked individuals were found in previous surveys
conducted in Sep. 2013, Mar. 2014 and Sep. 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.
3.6.17 The artificial bred individuals, if found, would be excluded from the
results of present monitoring programme in order to reflect the changes of
natural population. However, the mark on their prosoma might have been detached
during moulting after a certain period of release. The artificially released
individuals were no longer distinguishable from the natural population without
the specific chip sensor. The survey data collected would possibly cover both
natural population and artificially bred individuals.
Population difference among the sampling zones
3.6.18
Figure 3.2 and 3.3 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. In contrast,
much lower search record was found in other sampling zones especially TC2 (2
ind. in Sep. 2013, 1 ind. in Mar., Jun. and Sep. 2014). There was no spatial
difference of horseshoe crab size (prosomal width) among the sampling zones.
3.6.19 It was obvious that ST 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, TC3 might be functioning as less
important nursery ground adjacent to ST due to moderate but fluctuate number of
horseshoe crab found. Relatively, other sampling zones were not a suitable
nursery ground especially TC2. Possible factors were less area of suitable
substratum (especially TC1) and higher human disturbance (TC1 and TC2: close to
urban district and easily accessible). In TC2, large daily salinity fluctuation
was a possible factor either since it was flushed by two rivers under tidal
inundation. The individuals found in TC1, TC2 and TC3 were believed foraging
from the ST during high tide while it might return to ST over a certain period
of time. It accounted for the variable search records in the sampling zones
along the sampling months. For example, few individuals of Tachypleus tridentatus were found in TC1 only between Sep. 2012 and Sep. 2013. However it no
longer appeared while few individuals of Carcinoscorpius
rotundicauda were found after Mar. 2014.
Seasonal variation of horseshoe crab population
3.6.20 Throughout the monitoring period
conducted, the search record of horseshoe crab declined obviously during dry
season especially December (Figures 3.2 and 3.3 of Appendix O). In
present survey (Dec. 2014), 2 individuals of Carcinoscorpius rotundicauda and 8
individuals of Tachypleus
tridentatus were found only. Furthermore no
individual of either two species was found in the previous survey of Dec. 2013. As mentioned, the horseshoe crabs were inactive
and burrowed in the sediments during cold weather (<15 ºC). Similar results of low search record in dry season were reported in a
previous territory-wide survey of horseshoe crab. For example, the search
records in Tung Chung Wan were 0.17 ind. hr-1
person-1 and 0 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.
3.6.21
Between the sampling months Sep. 2012 and Dec. 2013, Carcinoscorpius rotundicauda was a less
common species relative to Tachypleus tridentatus. Only 4
individuals were ever recorded in ST in Dec. 2012. This species had been
believed of very low density in ST hence the encounter rate was very low. Until
Mar. 2014, it was found in all sampling zones with higher abundance in ST.
Based on its average size (mean prosomal width 39.28-49.81 mm), it indicated
that breeding and spawning of this species had occurred 3-4 years ago along the
coastline of Tung Chun Wan. However, these individuals were still small while
their walking trails were inconspicuous. Hence there was no search record in previous
sampling months. From Mar. to Sep. 2014, more individuals were recorded due to
larger size and higher activity.
3.6.22
For Tachypleus tridentatus, sharp increase of
number of individuals was recorded in ST with wet season (from Mar. to Sep. 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 period of
this year. The number of individuals increased in Mar. and Jun. 2014 followed
by a rapid decline in Sep. 2014. Apart from natural mortality, migration from
nursery soft shore to subtidal habitat was another possible cause. Since the
mean prosomal width of Tachypleus tridentatus continued
to grow and reached about 50 mm in this year. Most of the individuals might
have reached a suitable size strong enough to forage in subtidal habitat.
3.6.23
Figure 3.4 of Appendix O shows the changes of
prosomal width of horseshoe crab Carcinoscorpius rotundicauda and Tachypleus tridentatus in ST where was regarded as an important nursery
ground. As mentioned above, Carcinoscorpius rotundicauda was rarely
found between Sep. 2012 and Dec. 2013 hence the data were limiting. From Mar.
to Sep. 2014, the size of major population (50% records between upper and lower quartile) fluctuated
between 30-40 mm and 45-60
mm. Such fluctuation should be due to variable encounter rate influenced
by weather. For Tachypleus tridentatus, a consistent growing
trend was observed for the major population from Dec. 2012 to Dec. 2014.
regardless of change of search record. The prosomal width increased from 15-30
mm to 55-70 mm. As mentioned, the large individuals
might have reached a suitable size for migrating from the nursery soft shore to
subtidal habitat.
Impact of the HKLR project
3.6.24
The present survey was the eighth time of the EM&A programme during
the construction period. Based on the results, impact
of the HKLR project could not be detected on horseshoe crabs considering the
factor of natural, seasonal variation. In case, abnormal phenomenon (e.g. very few numbers of horseshoe crab individuals in warm weather, large number of dead individuals on the shore)
is observed, it would be reported as soon as possible.
Seagrass Beds
3.6.25 Table 3.3 of Appendix O show the records of
seagrass beds survey at
every sampling zone. Three small patches of Zostera japonica were found on sandy substratum nearby the seaward side of mangrove area at tidal
level 2.0 m above C.D. (Figure 3.5 of Appendix O). The estimated area ranged 0.3-4.2 m2 while
the estimated vegetation coverage was 20-40%. The total area and average area of seagrass beds were 4.7 m2
and 1.6 m2 respectively (Table 3.4 of Appendix O). Another
seagrass species Halophila
ovalis (Figure 3.5 of Appendix O). was no longer found in present
survey but it used to be abundant and extensive in previous surveys.
Temporal variation of seagrass beds
3.6.26 Figure 3.6 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 Mar. 2013 that grew within the
large patch of seagrass Halophila ovalis. Then the patch Jun.
2014, the patch size increased obviously again (41 m2) with warmer
climate. Similar to size increased and merged gradually with the warmer climate
from Mar. to Jun. 2013 (15 m2). However the patch size decreased
sharply and remained similar from Sep. 2013 (4 m2) to Mar. 2014 (3 m2).
In previous year, the patch size decreased again and remained similar Sep. 2014
(2 m2) to Dec. 2014 (5 m2, present survey).
3.6.27 For Halophila ovalis, it was recorded as 3-4 medium to large patches (area 18.9-251.7 m2;
vegetation coverage 50-80%) beside the mangrove vegetation at tidal level 2 m
above C.D in the Dec. 2013 (first survey). The total seagrass bed area grew steadily from 332.3 m2 in
Sep. 2012 to 727.4 m2 in Dec. 2013. Flowers could be observed in the
largest patch during its flowering period in Dec. 2013. In Mar. 2014, 31 small to
medium patches were newly recorded (variable area 1-72 m2 per patch,
vegetation coverage 40-80% per patch) in lower tidal zone between 1.0 and 1.5 m
above C.D. The total seagrass area increased further to 1350 m2. In
Jun. 2014, these small and medium patches grew and extended to each 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 Sep. 2014, the total seagrass area declined
sharply to 1111 m2. There were only 3-4 small to large patches
(6-253 m2) at high tidal level and 1 patch at low tidal level (786 m2). Typhoon or strong water current was a possible cause (Fong, 1998). In Sep. 2014,
there were two tropical cyclone records in Hong Kong (7th-8th
Sep.: no cyclone name, maximum signal number 1; 14th-17th
Sep.: Kalmaegi maximum signal number 8SE) before the seagrass survey dated 21st
Sep. 2014. The strong water current caused by the cyclone, Kalmaegi especially,
might have given damage to the seagrass beds. In addition, natural heat stress
and grazing force were other possible causes reducing seagrass beds area.
Besides, 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.
3.6.28
In Dec. 2014 (present survey), all the
seagrass patches of Halophila ovalis disappeared in ST. The seagrass bed of Halophila ovalis recorded in December survey was significantly different from the baseline condition. Figure 3.7 of Appendix O shows the difference of
the original seagrass beds area nearby the mangrove vegetation at high tidal
level between Jun. 2014 and Dec. 2014. Such rapid loss would not be seasonal
phenomenon because the seagrass beds at higher tidal level (2.0 m above C.D.)
were present and normal in December 2012 and 2013. According to Fong (1998),
similar incident had occurred in ST in the past. The original seagrass area had
declined significantly during the commencement of the construction and
reclamation works for the international airport at Chek Lap Kok in 1992. The seagrass
almost disappeared in 1995 and recovered gradually after the completion of
reclamation works. Moreover, incident of rapid loss of seagrass area was also
recorded in another intertidal mudflat in Lai Chi Wo in 1998 with unknown
reason. Hence Halophila
ovalis was regarded as a short-lived
and r-strategy seagrass that can
colonize areas in short period but disappears quickly under unfavourable
conditions (Fong, 1998).
Unfavourable
conditions to seagrass Halophila ovalis
3.6.29 Typhoon or strong water current was suggested as one unfavourable condition to Halophila ovalis (Fong, 1998). As
mentioned above, there were two tropical cyclone records in Hong Kong in Sep.
2014. The strong water current caused by the cyclones might have given damage
to the seagrass beds.
3.6.30 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).
3.6.31 In order to investigate any
deterioration of water quality (e.g. more turbid) in ST, the water quality measurement
results at two closest monitoring stations SR3 and IS5 of the EM&A
programme were obtained from the water quality monitoring team. Based on the
results from June to December 2014, the overall water quality was in normal
fluctuation except there was one exceedance of suspended solids (SS) at both
stations in September. On 10th Sep., 2014, the SS concentrations
measured 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 Sep. 2014 (daily total rainfall at
the Hong Kong International Airport: 0-2.1 mm; extracted from the
climatological data of Hong Kong Observatory). The effect of upstream runoff on
water quality should be neglectable in that period. Moreover the exceedance of
water quality was considered unlikely to be related to the contract works of
HKLR according to the ¡¥Notifications of Environmental Quality Limits
Exceedances¡¦ provided by the respective environmental team. The respective
construction of seawall and stone column works, which possibly caused turbid
water, were carried out within silt curtain as recommended in the EIA report.
Moreover there was no leakage of turbid water, abnormity or malpractice
recorded during water sampling. In general, the exceedance of suspended solids
concentration was considered to be attributed to other external factors, rather
than the contract works.
3.6.32 Based on the weather condition
and water quality results in ST, the co-occurrence of cyclone hit and turbid
waters in Sep. 2014 might have combined the adverse effects on Halophila ovalis that leaded to disappearance of this short-lived and r-strategy seagrass species. Fortunately
Halophila ovalis was a fast-growing
species (Vermaat et al., 1995). Previous studies showed that the
seagrass bed could be recovered to the original sizes in 2 months through
vegetative propagation after experimental clearance (Supanwanid, 1996).
Moreover it was reported to recover rapidly in less than 20 days after dugong
herbivory (Nakaoka and Aioi, 1999). As mentioned, the disappeared seagrass in
ST in 1995 could recover gradually after the completion of reclamation works
for international airport (Fong, 1998). The seagrass beds of Halophila ovalis might recolonize the
mudflat of ST through seed reproduction as long as there was no unfavourable
condition in the coming months.
Impact of the HKLR project
3.6.33 The present survey was the ninth
survey of the EM&A programme during the construction period. Based on the results, there was a complete
disappearance of seagrass Halophila
ovalis in the sampling zone ST. The combined effects of cyclone hits and
turbid water incidence in Sep. 2014 were believed the cause. For the turbid
water incidence (i.e. exceedance of SS concentration), there was no evidence
indicating correlation between the turbid water and the contract works of HKLR
(e.g. construction of seawall, stone column works)
as mentioned above. Hence
the negative impact of HKLR project on the seagrass was not significant.
3.6.34 As long as there is no unfavourable condition to Halophila ovalis, it is believed that
the seagrass beds would recover gradually in ST in the coming months. Because
it is a r-strategy seagrass species that
can colonize areas in short period (Fong, 1998).
3.6.35 Recently no follow-up action is
suggested. In case the disappearance of seagrass beds Halophila ovalis persists until June 2015, some follow-up actions should be taken. For
examples, more water quality parameters relevant to the seagrass toxicity (e.g.
herbicides and heavy metals) should be included in the water quality monitoring
programme. It is to investigate any seagrass toxicity present in the water that
is omitted in the original EM&A programme. Moreover, seagrass
transplantation may be adopted to fasten the recovery of seagrass beds.
Intertidal
Soft Shore Communities
3.6.36
Table 3.5 and Figure 3.8 of Appendix O show the types of
substratum along the horizontal transect at every tidal level of 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, the distribution of substratum varied
among three tidal levels. At high tidal level, there was higher percentage of
¡¥Gravels and Boulders¡¦ (50%) followed by ¡¥Sands¡¦ (30%) and ¡¥Soft mud¡¦ (20%). At
mid tidal level, ¡¥Gravels and Boulders¡¦ (90%) was the main substratum. At low
tidal level, there was higher percentage of ¡¥Sands¡¦ (50%) followed by ¡¥Gravels
and Boulders¡¦ (30%)¡¦and ¡¥Soft mud¡¦ (20%).
¡P
In TC2, high percentage of ¡¥Sands¡¦ (70%) were
recorded at all tidal levels. ¡¥Gravels and Boulders¡¦ (20-30%) was the second
abundant at high and mid tidal levels while ¡¥Soft mud¡¦ (20%) was the second
abundant at low tidal level.
¡P
In TC3, the distribution of substratum varied
among three tidal levels. High percentages of ¡¥Sands¡¦ (70%) was recorded at
high tidal level followed by ¡¥Soft mud¡¦ (30%). In contrast, high percentages of
¡¥Soft mud¡¦ (70%) was recorded at mid tidal level followed by ¡¥Sands¡¦ (30%).
¡¥Gravels and Boulders¡¦ was the major substratum type (70%) at low tidal level.
¡P
In ST, ¡¥Gravels and Boulders¡¦ (100%) was the
major substratum at high and mid tidal levels. ¡¥Soft mud¡¦ (50%) and ¡¥Sands¡¦
(40%) were mainly recorded at low tidal level.
3.6.37
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.
3.6.38 Table 3.6 of Appendix O lists the total abundance, density and number of taxon of every phylum in
the present survey.
A total of 10051 individuals
were recorded. Mollusca was significantly the most abundant phylum (total
individuals 9813, density 327 ind. m-2, relative
abundance 97.6%).
The second abundant phylum
was Arthropoda (105 ind.,
4 ind. m-2, 1.0%). The third abundant phylum was Annelida (80 ind., 3 ind. m-2, 0.8%). Relatively
other phyla were very low in abundances (density £1 ind. m-2, relative
abundance £0.3%). Moreover, the most diverse phylum was Mollusca (37 taxa) followed by Arthropoda (11 taxa)
and Annelida (10 taxa). There was one taxon
recorded only in other phyla. The complete list of collected specimens is shown in Annex III of Appendix O.
3.6.39
Table 3.7 of Appendix O shows the number of individual, relative abundance and density of each phylum in every sampling
zone. The total abundance (1528-4072 ind.) varied
largely among the four sampling zones although the phyla distributions were similar. In general, Mollusca was the most dominant phylum (no. of individuals: 1455-3999 ind.; relative abundance 95.2-98.2%; density
194-533 ind. m-2). Other phyla were significantly lower in number of individuals. Arthropoda (12-38
ind.; 10.5-2.5%; 2-5 ind. m-2) and Annelida (12-32 ind.;
0.5-1.5%; 2-4 ind. m-2) were the second or third abundant phyla. In ST, Cnidaria (sea anemone) was the forth abundant phylum (12 ind.; 0.6%; 2 ind. m-2). Relatively, other phyla were low in abundance among the four sampling zones (< 0.5%).
Dominant species in every sampling zone
3.6.40
Table 3.8 of Appendix O lists the abundant
species (relative abundance >10%) in every sampling zone. In TC1, gastropod Batillaria multiformis was the
most abundant (203 ind. m-2, relative abundance 73%) at high tidal level (major substrata: ¡¥Gravels
and Boulders¡¦ and ¡¥Sands¡¦). At mid and low tidal levels (major substrata: ¡¥Gravels and Boulders¡¦
and ¡¥Sands¡¦), rock
oyster Saccostrea cucullata (151-176 ind.
m-2, 39-53%, attached on boulders) and gastropod Monodonta
labio (40-76 ind. m-2, 12-19%) were the first and second abundant taxa. Moreover gastropod Batillaria multiformis was the
third abundant (72 ind. m-2, 18%) at mid
tidal levels.
3.6.41
At TC2, gastropods Cerithidea djadjariensis (68 ind. m-2, 36%), Cerithidea cingulata (26 ind. m-2, 14%) and
rock oyster Saccostrea
cucullata (43 ind. m-2, 26%) were common taxa at low-moderate densities (major substratum: ¡¥Sands¡¦). At mid and low tidal levels (major substrata: ¡¥Sands¡¦), rock oyster Saccostrea
cucullata (84-136 ind. m-2, 51-52%) was the most abundant followed by gastropod Batillaria zonalis (32-39 ind. m-2, 12-24%) at low-moderate densities. Moreover, gastropod Cerithidea djadjariensis (27 ind. m-2, 10%) was another
common taxon at low-moderate density at mid tidal levels.
3.6.42 At TC3,
gastropod Batillaria
multiformis (549 ind. m-2, 66%) was high in density at high tidal level
followed by gastropod Cerithidea djadjariensis (180 ind. m-2, 22%) at moderate density (major substratum:
¡¥Sands¡¦). At mid tidal level (major substratum: ¡¥Soft mud¡¦), gastropod Cerithidea djadjariensis (176 ind. m-2, 54%) was
the most abundant at moderate density followed by gastropod Cerithidea
cingulata (69 ind. m-2, 21%). At low tidal level
(major substratum: ¡¥Gravels and Boulders¡¦), rock oyster Saccostrea cucullata (208 ind. m-2, 44%) was the most abundant at moderate density
followed by gastropods Monodonta labio (126 ind. m-2,
27%) and Batillaria
multiformis (49 ind. m-2, 10%) at much lower densities.
3.6.43 At ST, gastropod
Batillaria multiformis was most
abundant (106 ind. m-2, 35%) at moderate density at high tidal level
(major substratum: ¡¥Gravels and Boulders¡¦) followed by much less abundant gastropod Monodonta labio (68 ind. m-2, 23%) and
rock oyster Saccostrea cucullata (59 ind. m-2, 20%). At
mid tidal level (major substratum: ¡¥Gravels and Boulders¡¦), rock oyster Saccostrea cucullata (145 ind. m-2, 37%) was the most abundant at moderate density.
Other less abundant taxa were gastropods Lunella coronata (66 ind. m-2, 17%), Monodonta labio (64 ind. m-2, 16%) and Batillaria
multiformis (38 ind. m-2, 10%) at low densities. At low tidal level (major
substrata: ¡¥Sands¡¦ and ¡¥Soft mud¡¦), rock oyster Saccostrea
cucullata (26 ind. m-2, 31%), gastropods Batillaria
zonalis (20 ind. m-2, 24%) and Lunella coronata (9 ind. m-2, 11%) were abundant taxa at low densities
relative to that at high and mid tidal levels.
3.6.44 There was no consistent zonation
pattern of species distribution observed across all sampling zones and tidal levels. The species distribution should be affected by the type of substratum primarily. In general, gastropods Batillaria multiformis (total number of individuals: 2683 ind., relative abundance 26.7%) and
Cerithidea djadjariensis (1274 ind., 12.7%) were the most commonly
occurring species on sandy and soft mud substrata. Rock oyster Saccostrea cucullata (2646 ind., 26.3%) and gastropod Monodonta
labio (1041 ind., 10.4%) were commonly occurring species inhabiting gravel and boulders substratum.
Biodiversity and abundance of soft shore
communities
3.6.45
Table 3.9 of Appendix O shows the mean values of
number of species, density, biodiversity index H¡¦ and species
evenness J of soft shore communities at every tidal level and in every sampling zone. Among the sampling zones, there was no clear difference in the mean
number of species (5-14 spp. 0.25 m-2). But the mean densities of
TC3 (328-828 ind. m-2) were highest followed by TC1 (280-390 ind. m-2)
and ST (84-396 ind. m-2). TC2 was relatively lowest at mean
densities (164-261 ind. m-2). The mean H¡¦ (1.57) and J (0.75) in ST were relatively higher
than that in TC1, TC2 and TC3 (H¡¦:
1.15-1.33; J: 0.60-0.69).
3.6.46 Across the tidal levels, there
was no consistent difference of the mean number of species, H¡¦ and J in all sampling zones. The mean densities were similar among the
three tidal levels in TC1 (280-390 ind. m-2) and TC2 (164-261 ind. m-2).
In TC3, the mean density at high tidal level (828 ind. m-2) was much
higher than mid and low tidal levels (328-472 ind. m-2). In ST, the
mean densities at high and mid tidal levels (300-396 ind. m-2) were
much higher than low tidal level (84 ind. m-2).
3.6.47
Figures 3.9 to 3.12 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. No consistent
temporal change of any biological parameters was observed. All the parameters
were under slight and natural fluctuation with the seasonal variation. Focused
on present survey (Dec. 2014), declines of mean density was observed in TC1,
TC2 and ST. It was believed the cause of higher mortality during cold, dry
season.
Impact of the HKLR project
3.6.48
The present survey was the ninth survey of the EM&A programme during
the construction period. Based on the results, impacts
of the HKLR project were not
detected on intertidal soft shore community. In case, abnormal phenomenon (e.g. large reduction of fauna densities and species number) is observed, it would be reported as soon as
possible.
3.7.1
The Contractor registered with EPD as a Chemical
Waste Producer on 12 July 2012 for the Contract. Sufficient numbers of
receptacles were available for general refuse collection and sorting.
3.7.2
The summary of waste flow table is detailed in Appendix K.
3.7.3
The Contractor was reminded that chemical waste
containers should be properly treated and stored temporarily in designated
chemical waste storage area on site in accordance with the Code of Practise on
the Packaging, Labelling and Storage of Chemical Wastes.
3.8
Environmental Licenses and Permits
3.8.1
The valid environmental licenses and permits
during the reporting period are summarized in Appendix L.
4
Environmental Complaint and
Non-compliance
4.1.1
The detailed air quality, noise, water quality and dolphin exceedances
are provided in Appendix M. Also,
the summaries of the environmental exceedances are presented as follows:
Air Quality
4.1.2 No Action and Limit Level
exceedances of 1-hour TSP and no Limit Level exceedance of 24-hour TSP were
recorded at AMS5 and AMS6 during the reporting period.
4.1.3 An Action Level exceedance
of 24-hour TSP at AMS5 was recorded on 21 January 2015. An Action Level
exceedances of 24-hour TSP at AMS6 was recorded on 16 December 2014 and 21 January 2015 respectively.
Noise
4.1.4
There were no Action and Limit Level exceedances for noise during
daytime on normal weekdays of the
reporting period.
Water Quality
4.1.5 During
the reporting period, five Action Level exceedances and two Limit
Level exceedances for suspended solid level were recorded. No exceedances of Action and Limit Level for
dissolved oxygen level and turbidity were recorded. There were no specific activities recorded during the
monitoring period that would cause any significant impacts on monitoring
results and no leakage of turbid water or any abnormity or malpractice was
observed during the sampling exercise. Therefore, all exceedances were considered as
non-contract related. The detailed numbers of
exceedances recorded during the reporting period at each impact station are summarised in Table 4.1.
Dolphin
4.1.6
There was one Limit Level exceedance of dolphin monitoring for the
quarterly monitoring data (December 2014 ¡V February 2015). According to the contractor¡¦s information, the
marine activities undertaken for HKLR03 during the quarter of December 2014 to
February 2015 included reclamation, excavation of stone platform, surcharge
activities, construction of seawall, temporary drainage diversion and ground
investigation.
4.1.7
There is no evidence showing the current LL
non-compliance directly related to the construction works of HKLR03 (where the
amounts of working vessels for HKLR03 have been decreasing), although the
generally increased amount of vessel traffic in NEL during the impact phase
October 2012. It should also be noted that reclamation work under HKLR03
(adjoining the Airport Island) situates in waters which has rarely been used by
dolphins in the past, and the working vessels under HKLR03 have been travelling
from source to destination in accordance with the Marine Travel Route to
minimize impacts on Chinese White Dolphin.
In addition, the contractor will implement proactive mitigation measures
such as avoiding anchoring at Marine Department¡¦s designated anchorage site ¡V
Sham Shui Kok Anchorage (near Brothers Island) as far as practicable.
4.1.8 All dolphin protective measures
are fully and properly implemented in accordance with the EM&A Manual.
According to the Marine Travel Route Plan, if vessels are crossing along edge
of the proposed marine park, the travelling speed will keep not exceeding 5
knots when crossing the edge of the proposed marine park. The Contractor will
continue to provide training for skippers to ensure that their working vessels
travel from source to destination to minimize impacts on Chinese White Dolphin
and avoid anchoring at Marine 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.
Table 4.1 Summary
of Water Quality Exceedances
Station
|
Exceedance Level
|
DO (S&M)
|
DO (Bottom)
|
Turbidity
|
SS
|
Total Number of Exceedances
|
Ebb
|
Flood
|
Ebb
|
Flood
|
Ebb
|
Flood
|
Ebb
|
Flood
|
Ebb
|
Flood
|
IS5
|
Action Level
|
--
|
--
|
--
|
--
|
--
|
--
|
26
Jan 2015
|
--
|
1
|
0
|
Limit Level
|
--
|
--
|
--
|
--
|
--
|
--
|
--
|
--
|
0
|
0
|
IS(Mf)6
|
Action Level
|
--
|
--
|
--
|
--
|
--
|
--
|
--
|
--
|
0
|
0
|
Limit Level
|
--
|
--
|
--
|
--
|
--
|
--
|
--
|
--
|
0
|
0
|
IS7
|
Action Level
|
--
|
--
|
--
|
--
|
--
|
--
|
--
|
--
|
0
|
0
|
Limit Level
|
--
|
--
|
--
|
--
|
--
|
--
|
--
|
--
|
0
|
0
|
IS8
|
Action Level
|
--
|
--
|
--
|
--
|
--
|
--
|
--
|
--
|
0
|
0
|
Limit Level
|
--
|
--
|
--
|
--
|
--
|
--
|
--
|
--
|
0
|
0
|
IS(Mf)9
|
Action Level
|
--
|
--
|
--
|
--
|
--
|
--
|
--
|
12 Jan 2015
|
0
|
1
|
Limit Level
|
--
|
--
|
--
|
--
|
--
|
--
|
5
Dec 2014
|
--
|
1
|
0
|
IS10
|
Action Level
|
--
|
--
|
--
|
--
|
--
|
--
|
--
|
21 Jan 2015
|
0
|
1
|
Limit Level
|
--
|
--
|
--
|
--
|
--
|
--
|
--
|
--
|
0
|
0
|
SR3
|
Action Level
|
--
|
--
|
--
|
--
|
--
|
--
|
--
|
--
|
0
|
0
|
Limit Level
|
--
|
--
|
--
|
--
|
--
|
--
|
--
|
--
|
0
|
0
|
SR4
|
Action Level
|
--
|
--
|
--
|
--
|
--
|
--
|
--
|
--
|
0
|
0
|
Limit Level
|
--
|
--
|
--
|
--
|
--
|
--
|
--
|
--
|
0
|
0
|
SR5
|
Action Level
|
--
|
--
|
--
|
--
|
--
|
--
|
--
|
21 Jan 2015
23 Jan 2015
|
0
|
2
|
Limit Level
|
--
|
--
|
--
|
--
|
--
|
--
|
--
|
--
|
0
|
0
|
SR10A
|
Action Level
|
--
|
--
|
--
|
--
|
--
|
--
|
--
|
--
|
0
|
0
|
Limit Level
|
--
|
--
|
--
|
--
|
--
|
--
|
--
|
23 Jan 2015
|
0
|
0
|
SR10B
|
Action Level
|
--
|
--
|
--
|
--
|
--
|
--
|
--
|
--
|
0
|
0
|
Limit Level
|
--
|
--
|
--
|
--
|
--
|
--
|
--
|
--
|
0
|
0
|
Total
|
Action
|
0
|
0
|
0
|
0
|
0
|
0
|
1
|
4
|
5**
|
Limit
|
0
|
0
|
0
|
0
|
0
|
0
|
1
|
1
|
2**
|
Notes:
S: Surface;
M: Mid-depth;
** The
total exceedances.
4.2
Summary of Environmental Complaint, Notification of
Summons and Successful Prosecution
4.2.1
There were two environmental
complaints received during the reporting period. The summary of environmental
complaints is presented in Table 4.2. The
details of cumulative statistics of Environmental Complaints are provided in Appendix N.
Table 4.2 A
Summary of Environmental Complaints for the Reporting Period
Environmental Complaint No.
|
Date of Complaint Received
|
Description of Environmental Complaints
|
COM-2014-063
|
3
December 2014
|
Noise
|
COM-2014-065
|
24
December 2014
|
Water
Quality
|
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:
¡±
The Contractor was reminded to remove the rubbish from the shore of S16, S7, S11, S15, S22, S25, N1 and N20.
¡± The Contractor was reminded to
provide a drip tray for the chemical containers on vessel Sing Kee, N1 and N4.
¡± The Contractor was reminded to
spray water on the stockpile of fill material at N13.
¡± The Contractor was reminded to
remove the stagnant water from the drip tray at N4.
¡± The Contractor was reminded to
clean up the oil stains on the unpaved road at N13.
¡± The Contractor was reminded to remove the rubbish in the U channel and
divert the wastewater to a treatment facility for treatment at N13.
¡±
The Contractor was reminded to provide a drip tray for the oil drums at S11 and S25.
¡± The Contractor was reminded to
provide sorting for the waste generated from the Contact and disposed of them
regularly.
¡± The Contractor was reminded to
clean up the stagnant water at N1, N20, S11, S19, WA4 and WA6.
¡± The Contractor was reminded to
replace the broken rubbish bin at N13.
¡± The Contractor was reminded to
clean up the oil stains inside the sheet pile at S11.
¡±
The Contractor was reminded to spray water during the percussive
activity at S15.
¡± The Contractor was reminded to
clean up the slurry which observed on barge edge of vessel Shun Tat 82.
¡± The Contractor was reminded to
remove the excess fill material on barge edge of vessel Kiu Tak.
¡± The Contractor was reminded to
clean up the muddy water at S7 and S8.
¡±
The Contractor was reminded to clean up the oil stains and provide a
drip tray for the air compressor at N4.
¡± The Contractor was reminded to
replace the broken sand bags along the barge edge.
¡± The Contractor was asked to stop
discharging the untreated wastewater into the sea at S11 and treat the
wastewater prior to discharge.
¡±
The Contractor was reminded to clean up the sundries at S15.
¡± The Contractor was reminded to
spray water for the stockpiles of fill material at S22 a d N13.
¡± The Contractor was reminded to
remove the crushed stones and keep functional of the wheel washing bay at N20.
¡± The Contractor was reminded to
provide bunds/sand bags along gullies at N20 to prevent washing away of sand
into the gullies.
¡± The Contractor was reminded to
provide a standard wheel washing facility at S8A.
¡± The Contractor was reminded to
divert the muddy water to a waste water facility for treatment prior to
discharge.
¡± The Contractor was reminded to
close the gap between silt curtain sections at Portion X.
¡± The Contractor was reminded to
provide a cover for the rubbish bin at N4.
¡± The Contractor was reminded to
place sand bags around the gully at N20.
¡±
The Contractor was reminded to provide a drip tray and labels for
chemical containers at N20.
¡± The Contractor was reminded to
treat the wastewater properly at N4.
¡± The Contractor was reminded to
provide the sand bags around the gutter to prevent washing away of silt/sand
into the drainage system at N20.
¡± The Contractor was reminded to
remove the broken water barrier at S7
¡± The Contractor was reminded to
provide water spray for the breaking activity at S11.
¡±
The Contractor was reminded to fully enclose the cement mixing plant at
S15.
¡± The Contractor was reminded to
remove the excess rubbish regularly at N1 and S19.
¡± The Contractor was reminded to
remove the concrete waste at N13.
¡± The Contractor was reminded to
provide water spraying for the dry unpaved road at S16.
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 tenth Quarterly EM&A
Report which summarises the
monitoring results and audit findings of the EM&A programme during the
reporting period from 1 December 2014 to 28 February
2015.
Air Quality
5.3.2
For AMS5, no Action and Limit Level exceedances of 1-hr TSP and 24-hr
TSP were recorded at AMS 5
during the reporting period.
5.3.3
For AMS6, no Action and Limit Level exceedances
of 1-hr TSP level and no Limit Level exceedances of 24-hr TSP were recorded
during the reporting period. An Action Level exceedance of 24-hr TSP level was
recorded on 15 and 27 October 2014, respectively.
Noise
5.3.4
For construction noise, there
were no Action Level and Limit Level exceedances during the reporting
period.
Water Quality
5.3.5
During the reporting period, nine Action Level
exceedances and three Limit Level exceedances of suspended solid level were
recorded. No Action and Limit Level exceedances of dissolved oxygen level were
recorded. No Action
and Limit Level exceedances of turbidity
were recorded.
Dolphin
5.3.6
There was one Limit Level exceedance of dolphin monitoring for the
quarterly monitoring data (December
2014 ¡V February 2015).
5.3.7
During this quarter of dolphin
monitoring, no adverse impact from the activities of this construction project
on Chinese White Dolphins was noticeable from general observations.
5.3.8
Although dolphins rarely
occurred in the area of HKLR03 construction in the past and during the baseline
monitoring period, it is apparent that dolphin usage has been significantly
reduced in NEL in 2012-15, and many individuals have shifted away from the
important habitat around the Brothers Islands.
5.3.9
It is critical to monitor the
dolphin usage in North Lantau region in the upcoming quarters, to determine
whether the dolphins are continuously affected by the various construction
activities in relation to the HZMB-related works, and whether suitable
mitigation measure can be applied to revert the situation.
Mudflat
-Sedimentation Rate
5.3.10 This measurement result was
generally and relatively higher than the baseline measurement at S1, S2, S3 and
S4. The mudflat level is continuously increased.
5.3.11 Impact
water quality monitoring in San Tau (monitoring station SR3) was conducted in December
2014. The monitoring parameters included dissolved
oxygen (DO), turbidity and suspended solids (SS).
Mudflat - Ecology
5.3.12
The December 2014 survey was the ninth survey of the EM&A programme
during the construction period. Based on the results, impacts of the HKLR project were not detected on horseshoe crabs and intertidal soft shore community. It
was found that there was a complete
disappearance of seagrass Halophila
ovalis in the sampling zone ST. The combined effects of cyclone hits and
turbid water incidence in Sep. 2014 were believed the cause. For the turbid
water incidence (i.e. exceedance of SS concentration), there was no evidence
indicating correlation between the turbid water and the contract works of HKLR
(e.g. construction of seawall, stone column works)
as mentioned above. Hence
the negative impact of HKLR project on the seagrass was not significant.
Recently no follow-up action is suggested. In case the disappearance of
seagrass beds Halophila ovalis persists until June 2015, some follow-up
actions should be taken.
Environmental Site
Inspection and Audit
5.3.13
Environmental site inspection
was carried out on 3, 10,
17, 24 and 30 December 2014, 7, 14, 21 and 30 January 2015 and
4, 11, 17 and 27 February 2015. Recommendations on
remedial actions were given to the Contractors for the deficiencies identified
during the site inspections.
5.3.14 There were two environmental complaints received during the
reporting period.
5.3.15
No notification of summons and
prosecution was received during the reporting period.
Environmental Management
Structure
Construction Programme
Location
of Works Areas
Event and Action Plan
Implementation Schedule of
Environmental Mitigation Measures
Site Audit Findings and Corrective Actions
Air
Quality Monitoring Data and Graphical Plots
Noise
Monitoring Data and Graphical Plots
Water
Quality Monitoring Data and Graphical Plots
Dolphin Monitoring Results
Waste Flow Table
Summary
of Environmental Licenses and Permits
Record of ¡§Notification of
Environmental Quality Limit Exceedances
Cumulative Statistic on
Complaints
Mudflat Monitoring Results