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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.8 (Jun 2014 to Aug 2014)
27 November 2014
Revision 2
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/C for HKLR and EP-353/2009/G for
HKBCF were issued on 5 September 2013 and 6 August 2013, 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 Eighth 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 June to 31 August 2014.
Environmental
Monitoring and Audit Progress
The EM&A programme
were undertaken in accordance with the Updated EM&A Manual for HKLR
(Version 1.0). A summary of the
monitoring activities during this reporting period is presented as below:
Monitoring Activity
|
Monitoring Date
|
June 2014
|
July 2014
|
August 2014
|
Air
Quality
|
1-hr TSP
|
3, 6, 12,
18, 24 and 30
|
4, 10,
16, 22 and 28
|
1, 7, 13,
19, 25 and 29
|
24-hr TSP
|
AMS5:
6,11, 17, 23 and 27
AMS6:
5,11, 17, 23 and 27
|
AMS5: 3, 9, 15, 21, 25 and 31
AMS6: 4, 9, 15, 21, 25 and 31
|
5, 11,
15, 21 and 27
|
Noise
|
3, 12, 18
and 24
|
4, 10,
16, 22 and 28
|
7, 15, 22
and 25
|
Water
Quality
|
2, 4, 6,
9, 11, 13, 16, 18, 20, 23, 25, 27 and 30
|
2, 4, 7,
9, 11, 14, 16, 21, 23, 25, 28 and 30
|
1, 4, 6,
8, 11, 13, 15, 18, 20, 22, 25, 27 and 29
|
Chinese
White Dolphin
|
3, 5, 10
and 16
|
3, 9, 10,
14 and 21
|
5, 6, 15
and 19
|
Mudflat
Monitoring (Ecology)
|
1, 13,
14, 15 and 16
|
-
|
-
|
Mudflat
Monitoring (Sedimentation rate)
|
25
|
-
|
-
|
Site Inspection
|
4, 11, 18
and 27
|
2, 9, 16,
25 and 30
|
6, 13, 20
and 29
|
Due to boat
availability issue, the dolphin monitoring schedule was rescheduled from 18
June 2014 to 5 June 2014.
Due to the
electricity supply problem of high volume sampler, the 24-hr dust monitoring at
AMS5 was rescheduled from 5 June 2014 to 6 June 2014.
Due to the
electricity supply problem of high volume sampler, the 24-hr dust monitoring at
AMS6 was rescheduled from 3 July 2014 to 4 July 2014.
Due to boat
availability issue, the dolphin monitoring schedule was rescheduled from 8 July
2014 to 3 July 2014.
Water quality
monitoring on 18 July 2014 was cancelled for safety reason as strong wind
signal no. 3 was hoisted by Hong Kong Observatory.
Due to boat
availability issue, the dolphin monitoring schedule was rescheduled from 7
August 2014 to 6 August 2014.
Water quality
monitoring for mid-ebb tide on 13 August 2014 was cancelled for safety reason
as a thunderstorm warning was hoisted by Hong Kong Observatory.
Due to the inclement
weather on 13 August 2014 (red rainstorm signal was hoisted by Hong Kong
Observatory), dolphin monitoring schedule was rescheduled to 15 August
2014.
Due to the inclement
weather, the noise monitoring at NMS5 was rescheduled from 13 August 2014 to 15
August 2014 and from 19 August 2014 to 22 August 2014.
Breaches
of Action and Limit Levels
A summary of environmental exceedances for this
reporting period is as follows:
Environmental Monitoring
|
Parameters
|
Action Level (AL)
|
Limit Level (LL)
|
Air
Quality
|
1-hr TSP
|
0
|
0
|
24-hr TSP
|
0
|
0
|
Noise
|
Leq
(30 min)
|
0
|
0
|
Water
Quality
|
Suspended
solids level (SS)
|
2
|
0
|
Turbidity
level
|
0
|
0
|
Dissolved
oxygen level (DO)
|
10
|
0
|
Dolphin
Monitoring
|
Quarterly
Analysis (June to August 2014)
|
2
|
0
|
The Environmental Team investigated all
exceedances and found that they were not project related.
All investigation reports for exceedances of the
Contract have been submitted to ENPO/IEC for comments and/or follow up to
identify whether the exceedances occurred related to other HZMB contracts.
Implementation of Mitigation Measures
Site inspections were carried out on a weekly
basis to monitor the implementation of proper environmental pollution control
and mitigation measures for the Project.
Potential environmental impacts due to the construction activities were
monitored and reviewed.
Complaint Log
There were no complaints received in relation to
the environmental impacts during the reporting
period.
Notifications of Summons and Prosecutions
There were no notifications of summons or
prosecutions received during this reporting period.
Reporting Changes
This report has been developed in compliance
with the reporting requirements for the quarterly summary EM&A reports as
required by the Updated EM&A Manual for HKLR (Version 1.0).
The proposal for the change of Action Level and
Limit Level for suspended solid and turbidity was approved by EPD on 25 March
2013.
The revised Event and Action Plan for dolphin monitoring was approved by EPD on 6 May 2013.
The original monitoring station at IS(Mf)9
(Coordinate- East:813273, North 818850) was observed inside the perimeter silt
curtain of Contract HY/2010/02 on 1 July 2013, as such the original impact
water quality monitoring location at IS(Mf)9 was temporarily shifted outside
the silt curtain. As advised by the
Contractor of HY/2010/02 in August 2013, the perimeter silt curtain was shifted
to facilitate safe anchorage zone of construction barges/vessels until end of
2013 subject to construction progress.
Therefore, water quality monitoring station IS(Mf)9 was shifted to
813226E and 818708N since 1 July 2013.
According to the water quality monitoring team¡¦s observation on 24 March
2014, the original monitoring location of IS(Mf)9 was no longer enclosed by the
perimeter silt curtain of Contract HY/2010/02. Thus, the impact water quality
monitoring works at the original monitoring location of IS(Mf)9 has been
resumed since 24 March 2014.
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/C for HKLR and EP-353/2009/G for HKBCF were issued on 5 September
2013 and 6 August 2013, 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 Eighth 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
June to 31 August 2014.
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
Stone column
installation
¡P
Filling works
behind stone platform
¡P
Temporary stone
platform construction
¡P
Band drains
installationPiling Works
|
Portion Y
|
¡P
Access shaft construction
for Scenic Hill Tunnel (SHT) & HKBCF to Airport Tunnel (HAT)
¡P
Utility culvert
excavation
¡P
Pipe roofing
installation for Tunnel HAT
|
West Portal
|
¡P
Pipe roofing
installation and excavation of tunnel SHT
|
Airport Express Line
|
¡P
Pre-grouting and
pipe piling works for Airport Express Line (AEL) access shafts
|
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
|
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 .1 Summary
of 1-hour TSP Monitoring Results During the Reporting Period
Reporting Period
|
Monitoring
Station
|
Average (mg/m3)
|
Range (mg/m3)
|
Action Level (mg/m3)
|
Limit Level (mg/m3)
|
June 2014
|
AMS5
|
18
|
5 ¡V 41
|
352
|
500
|
AMS6
|
20
|
8 ¡V 38
|
360
|
July 2014
|
AMS5
|
16
|
4 - 52
|
352
|
AMS6
|
26
|
6 - 98
|
360
|
August 2014
|
AMS5
|
16
|
3 - 47
|
352
|
AMS6
|
17
|
8 - 40
|
360
|
Table 3.2 Summary
of 24-hour TSP Monitoring Results During the Reporting Period
Reporting Period
|
Monitoring
Station
|
Average (mg/m3)
|
Range (mg/m3)
|
Action Level (mg/m3)
|
Limit Level (mg/m3)
|
June 2014
|
AMS5
|
34
|
22 ¡V 54
|
164
|
260
|
AMS6
|
42
|
23 ¡V 74
|
173
|
July 2014
|
AMS5
|
35
|
17 - 66
|
164
|
AMS6
|
47
|
23 - 98
|
173
|
August 2014
|
AMS5
|
22
|
12 - 30
|
164
|
AMS6
|
41
|
17 - 83
|
173
|
3.2.2
For 1-hr TSP and 24-hr TSP, no Action and Limit Level exceedances were
recorded at AMS 5
and AMS 6 during the reporting period.
3.3
Noise Monitoring Results
3.3.1
The monitoring results for construction noise
are summarized in Table 3.3 and the
monitoring results and relevant graphical plots for this reporting
period are provided in Appendix H.
Table 3.3 Summary
of Construction Noise Monitoring Results During the Reporting Period
Reporting period
|
Monitoring
Station
|
Average Leq
(30 mins), dB(A)*
|
Range of Leq
(30 mins), dB(A)*
|
Action Level
|
Limit Level Leq
(30 mins), dB(A)
|
June 2014
|
NMS5
|
69
|
67 ¡V71
|
When one documented complaint is received
|
75
|
July 2014
|
60
|
56 ¡V66
|
August 2014
|
57
|
55 ¡V 59
|
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, two Action Level
exceedances of suspended solid level were recorded. Ten Action Level exceedances of dissolved oxygen
level were recorded. No Limit Level exceedance of suspended solid level and
dissolved oxygen level were recorded. No Action
and Limit Level exceedance of turbidity was 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 (June ¡V August 2014).
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 June to August 2014, 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 894.40 km of survey effort was collected with 93.6% 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, 343.21 km and 551.19
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 647.96 km, while the effort on secondary lines was 246.44 km. Both survey effort conducted on primary and
secondary lines were considered as on-effort survey data. Summary table of the survey effort is
shown in Annex I
of Appendix J.
3.5.12
During the six sets of monitoring surveys in June to August 2014, a total of 28 groups of 96
Chinese White Dolphins were sighted.
All except two dolphin sightings
were made during on-effort search. Twenty on-effort sightings were made on primary lines,
while another six on-effort sightings were made on
secondary lines. In this quarterly period, almost all dolphin
groups were
sighted in NWL,
with the exception of one group of four dolphins being sighted in NEL.
Summary table of the dolphin sightings is
shown in Annex II of Appendix J.
Distribution
3.5.13
Distribution of dolphin sightings made during monitoring surveys in June, July and August 2014 was shown in Figure 1 of Appendix J.
In this quarter,
the majority of dolphin sightings were made in the western end of the North
Lantau region, with higher concentration within and adjacent to the Sha Chau
and Lung Kwu Chau Marine Park (Figure 1 of Appendix J). Other
dolphin sightings were scattered to the west and northeast of airport
platform. The lone sighting made in
NEL was located to the north of Yam O at the eastern end of the survey area.
3.5.14
Notably, none of the dolphin groups was
sighted in the vicinity of the HKLR03/ HKBCF reclamation sites or along the
entire alignment of 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 (June to August 2014) was compared to the one during
the baseline monitoring period (September to November 2011). In the present quarter, dolphins have
mostly 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 abandonment of NEL region by the
dolphins have been consistently recorded in the past six quarters.
3.5.16
On the other hand, dolphin occurrence in the
northwestern portion of North Lantau region
was somewhat different between the baseline and impact phase quarters. During the present impact monitoring
period, there appeared to be much fewer dolphins occurred in the middle portion
of North Lantau region than 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 between Black Point and Lung Kwu Chau during the
baseline period than during the present impact monitoring period (Figure 1 of Appendix J).
A number of dolphin sightings were made to the west of Chek Lap Kok
airport (especially near the HKLR09 alignment) during the baseline period, but
only two sightings were made there during the present impact phase period.
3.5.17
As the baseline monitoring period was in the
autumn season while the present monitoring period was in the summer season, a
direct comparison in dolphin distribution between the two quarterly periods of
summer months in 2013 and 2014 was also made to avoid the potential bias
contributed by seasonal variation in distribution (Figure 2 of Appendix J).
3.5.18
Among the two summer periods, only one dolphin
sighting was made in NEL in the summer of 2014, while there were five sightings
made there in the summer of 2013.
Moreover, a lot more dolphin sightings were made in the middle and
western portions of North Lantau waters
(especially near Black Point, Pillar Point, to the north of airport platform
and near the HKLR09 alignment) in the summer of 2013 than in the summer of
2014.
Encounter
Rate
3.5.19
For the three-month study
period in June, July and August 2014, 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) from
each of the survey areas 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 in September to November 2011 (See Table 3.5).
Table 3.4 Dolphin
Encounter Rates (Sightings Per 100 km of Survey Effort) During three Reporting
Period (June ¡V August 2014)
Survey Area
|
Dolphin Monitoring
|
Encounter rate (STG)
(no. of on-effort dolphin sightings per 100 km of survey effort)
|
Encounter rate (ANI)
(no. of dolphins from all on-effort sightings per 100 km of survey effort)
|
Primary Lines Only
|
Primary Lines Only
|
Northeast Lantau
|
Set 1 (3 & 5 Jun
2014)
|
0.00
|
0.00
|
Set 2 (10 & 16 Jun
2014)
|
0.00
|
0.00
|
Set 3 (3, 9 & 10 Jul 2014)
|
2.54
|
10.16
|
Set 4 (14 & 21 Jul 2014)
|
0.00
|
0.00
|
Set 5 (5 & 6 Aug 2014)
|
0.00
|
0.00
|
Set 6 (15 & 19 Aug 2014)
|
0.00
|
0.00
|
Northwest Lantau
|
Set 1 (3 & 5 Jun 2014)
|
1.67
|
5.00
|
Set 2 (10 & 16 Jun 2014)
|
0.00
|
0.00
|
Set 3 (3, 9 & 10 Jul 2014)
|
3.03
|
10.61
|
Set 4 (14 & 21 Jul 2014)
|
8.40
|
26.60
|
Set 5 (5 & 6 Aug 2014)
|
5.63
|
22.52
|
Set 6 (15 & 19 Aug 2014)
|
9.70
|
40.40
|
Table 3.5 Comparison
of Average Dolphin Encounter Rates between Reporting Period (June ¡V August
2014) and Baseline Monitoring Period (Sep ¡V Nov 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
|
0.42 ¡Ó 1.04
|
6.00 ¡Ó 5.05
|
1.69 ¡Ó 4.15
|
22.19 ¡Ó 26.81
|
Northwest Lantau
|
4.74 ¡Ó 3.84
|
9.85 ¡Ó 5.85
|
17.52 ¡Ó 15.12
|
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
5.04 sightings and 17.54 dolphins per 100 km of survey effort respectively,
while the encounter rates of sightings (STG) and dolphins (ANI) in NEL were
0.29 sightings and 1.17 dolphins per 100 km of survey effort respectively.
3.5.21
In NEL, the average dolphin encounter rates (both STG and ANI) in the
present three-month impact monitoring period was only a small fraction of the
baseline value (i.e. less than 10%), and such low occurrence of dolphins in NEL
have been consistently recorded in the past six quarters (Table 3.6).
3.5.22
It is a serious concern that dolphin occurrence in NEL in the past six 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). In fact,
the present quarter was the seventh consecutive quarters being accessed that
have triggered the Action Level under the Event and Action Plan. 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.
3.5.23
Moreover, the average dolphin encounter rates (STG and ANI) in NWL
during the present impact phase monitoring period were also much lower
(reductions of 52% and 61% respectively) than the ones recorded in the 3-month
baseline period, indicating a noticeable decline in dolphin usage of this
survey area during the present construction period. In fact, both dolphin
encounter rates in summer 2014 have dropped to the lowest since the
commencement of the HKLR03 dolphin monitoring (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
|
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
|
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.
3.5.24
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
(seventh quarter of the impact phase being assessed), the p-value for the
differences in average dolphin encounter rates of STG and ANI were 0.0199 and
0.0597 respectively. If the alpha value is set at 0.1, 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 seven quarters of the impact phase being
assessed), the p-value for the differences in average dolphin encounter rates
of STG and ANI were 0.0037 and 0.0013 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 waters (especially around the Brothers Islands
and Shum Shui Kok) 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 could possibly link to the HZMB-related
construction activities in NEL waters, which include the 150 hectares of
habitat loss due to HKBCF reclamation, 23 hectares of habitat loss due to
HKLR03 reclamation, as well as the recently commenced TMCLKL construction that
involves intensive bored piling activities for the southern viaduct and further
reclamation of 16.5 hectares for the northern landfall.
3.5.28 During the present quarter, all dolphin protective
measures are fully and properly implemented in accordance with the EM&A
Manual. 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
anchorage site at Sham Shui Kok as far as practicable. With these
implemented measures in place, disturbance to the dolphins have been minimized
by the Contractor as far as practicable. This would create the
opportunity for dolphins' continuous usage of NEL waters, where a future marine
park around the Brothers Islands will be established in this important dolphin
habitat as a compensation measure for the habitat loss resulted from the HKBCF
reclamation works. Unless such declining trend can be reverted after the
establishment of the Brothers Islands Marine Park, there should be a
presumption against further reclamation in North Lantau waters as suggested
in Hung (2013, 2014).
3.5.29
It should be noted that dolphin usage in NWL
have also been greatly diminished progressively in the past few quarters (Table 3.7), and such trend should be continuously
monitored, as the potential impacts of HZMB-related works on the dolphins may
have been extended to the entire North Lantau region.
Group
Size
3.5.30
Group size of Chinese White Dolphins ranged from one to eight
individuals per group in North Lantau region during June ¡V August 2014. The
average dolphin group sizes from these three months were compared with the ones
deduced from the baseline period in September to November 2011, as shown in Table 3.8.
Table 3.8 Comparison
of Average Dolphin Group Sizes between Reporting Period (June ¡V August 2014) and Baseline Monitoring
Period (Sep¡V Nov 2011)
|
Average Dolphin Group Size
|
Reporting Period
|
Baseline Monitoring Period
|
Overall
|
3.43 ¡Ó 1.95 (n = 28)
|
3.72 ¡Ó 3.13 (n = 66)
|
Northeast Lantau
|
4.00 ¡Ó 0.00 (n = 1)
|
3.18 ¡Ó 2.16 (n = 17)
|
Northwest Lantau
|
3.41 ¡Ó 1.99 (n = 27)
|
3.92 ¡Ó 3.40 (n = 49)
|
3.5.31
The average dolphin group sizes in the entire North Lantau region as
well as in NWL waters during June ¡V August 2014 were lower than the ones
recorded during the three-month baseline period (Table 3.8). In fact, 17 of the 28 groups were composed of 1-3 individuals only,
while no dolphin group was composed of more than 10 individuals.
3.5.32
Distribution of dolphins with larger group sizes (five individuals or
more per group) during the present quarter is shown in Figure 3
of Appendix J, with
comparison to the one in baseline period. During the
summer of 2014, distribution of all larger dolphin groups were concentrated within
and around the Sha Chau and Lung Kwu Chau
Marine Park (Figure 3
of Appendix J). This distribution pattern was
quite 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). Notably none of the larger
dolphin groups were sighted near the HKLR03 reclamation site in the present
monitoring period (Figure 3
of Appendix J).
3.5.33
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
3.5.34
From June to August 2014,
the most heavily utilized habitats by Chinese White Dolphins mainly concentrated
within and
around the marine park area (Figures 4a and 4b
of Appendix J). Only
one grid in NEL recorded the presence of dolphins. 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.
3.5.35
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.
3.5.36
When compared with the habitat use patterns
during the baseline period, dolphin usage in NEL 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 the very rare occurrence of dolphins during the
present impact phase period (Figure 5
of Appendix J).
3.5.37
The density patterns between the baseline and
impact phase monitoring periods were also different in NWL, with higher dolphin
usage near Black Point, as well as between Pillar Point and airport platform
during the baseline period (Figure 5
of Appendix J).
3.5.38
The absence of dolphins in the identified important
habitats around the Brothers Islands and Shum Shui Kok in consecutive quarters
in 2013-14 is of serious concern. The future Brothers Islands Marine Park will be
established in this area upon the completion of HKBCF reclamation works, as an
important compensation measure for the associated habitat loss. As suggested recently in Hung (2014),
such low usage of dolphins in this important habitat in the past two years was
likely related to the on-going HZMB-related construction works. Continuous monitoring of such diminished
use should be continued in this important dolphin habitat in the upcoming quarters.
Mother-calf Pairs
3.5.39
During the three-month
study period, only
three unspotted juveniles (UJ) were sighted in
NWL survey areas. These young calves comprised of 3.1% of all animals sighted, which was much lower than the percentage recorded during the baseline
monitoring period (6.8%).
3.5.40
The few young calves were found near Lung Kwu
Chau, Sha Chau and Shum Wat (Figure 6 of Appendix J), which
was very different from their distribution pattern during the baseline period
when young calves were sighted throughout the NWL survey area as well as a few
sighted in NEL waters. None of
these young calves were sighted in the vicinity of the HKBCF/HKLR03 reclamation
sites and HKLR09/TMCLKL alignments during the present quarter (Figure 6 of Appendix J).
Activities
and Associations with Fishing Boats
3.5.41
A total of four dolphin sightings were associated with socializing and traveling activities during the three-month study
period. Notably, no feeding activity of dolphin
was observed during the present quarter, which was in contrast to the
relatively high percentage of feeding activities recorded during the baseline
period (11.6%). On the contrary,
the percentage of socializing activities during the present impact phase
monitoring period (7.1%) was slightly higher than the one recorded during the
baseline period (5.4%).
3.5.42
Distribution of dolphins engaged in socializing and traveling activities during the present three-month period is shown in Figure 7
of Appendix J. The two sightings associated with socializing activities occurred near
Sha Chau, while the two sightings associated with traveling activities were
found adjacent to Lung Kwu (Figure 7
of Appendix J). Distribution of dolphin sightings associated with these activities
during the impact phase was drastically different from the distribution pattern
of these activities during the baseline period (Figure 7
of Appendix J).
3.5.43
During the three-month period, none of the 28 dolphin groups was
found to be associated with an operating fishing vessels in North Lantau waters.
The 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
3.5.44
From June to August 2014, over
2,000 digital photographs of Chinese White Dolphins were taken
during the impact phase monitoring surveys for the photo-identification work.
3.5.45
In total, 32 individuals sighted 44 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 except four of these re-sightings
were made in NWL. Four individuals
(NL123, NL139, NL261 and NL285) were sighted once during the lone sighting made
in NEL in the present quarter.
3.5.46
Almost all identified
individuals were sighted only once or twice during the three-month period, with
the exception of one individual (NL272) being sighted thrice.
3.5.47
Notably
11 of these 32 individuals were also sighted in West
Lantau waters during the HKLR09 monitoring surveys during the same three-month
period, showing their extensive movement between North and West Lantau
regions. In particular, two
individuals (NL139 and NL261) were sighted in both NEL and WL during the same
quarter.
3.5.48
Six well-recognized females
(NL93, NL104, NL123, NL145, NL202 and WL124) were accompanied with their calves
during their re-sightings. Most of
these mothers were frequently sighted with their calves throughout the HKLR03
impact phase monitoring period since October 2012.
Individual
range use
3.5.49
Ranging patterns of the 32 individuals identified during the three-month
study period were determined by fixed kernel method, and are shown in Annex V of Appendix J.
3.5.50
With the exception of a few
individuals, most identified dolphins sighted in this quarter were utilizing
their range use in NWL (and some also in WL), 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.
3.5.51 For many individuals that have
previously utilized the Brothers Islands as their major core area of activities, they have apparently shifted their range use away from
this important habitat (e.g. NL93, NL123, NL136, NL261;
Annex V of Appendix J). Such shifts of range use and core area
use were also documented by Hung (2014) as well as in
the past monitoring quarters in 2013 and 2014 under the present study.
3.5.52
The diminished or abandoned usage of NEL waters by a large number of
individual dolphins coincided well with the noticeable decline in dolphin
occurrence in NEL as discussed in Sections 3.5.13 to 3.5.27. This is of serious
concern, as the Brothers Islands in NEL was once identified an important
habitat for many year-round residents that focused their core area use there
(Hung 2008, 2013). Therefore, the
ranging pattern of individual dolphins should be continuously monitored around
Lantau waters, and measures should be taken to ensure that dolphins will
continue to move between NWL and NEL without any hindrance as a result of the
HZMB-related construction works.
3.5.53
On the other hand, there were a
number of individuals sighted in NWL and NEL waters consistently in the past,
but have extended their range use to WL waters in the present quarter (e.g.
CH34, NL46, NL136, NL139, NL261; Annex V
of Appendix J). 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
3.5.54
There
were two Action Level exceedances of dolphin monitoring for the quarterly monitoring data (June ¡V August 2014). According to the contractor¡¦s
information, the
marine activities undertaken for HKLR03 during the quarter of June 2014 to
August 2014 included stone platform construction, reclamation, stone column
installation, band drain installation, excavation of stone platform, surcharge
activities, construction of seawall and temporary drainage diversion. There is
no evidence showing the current AL non-compliances directly related
to the construction works of HKLR03, although the generally increased amount of
vessel traffic in NEL during the impact phase has been partly contributed by
HKLR03 works since October 2012. It
should also be noted that reclamation work under HKLR03 (adjoining the Airport
Island) situates in waters which has rarely been used by dolphins in the past,
and the working vessels under HKLR03 have been travelling from source to
destination in accordance with the Marine Travel Route to minimize impacts on
Chinese White Dolphin. 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.
3.5.55
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).
3.5.56 For the comparison between the baseline period and
the present quarter (seventh quarter of the impact phase being assessed), the
p-value for the differences in average dolphin encounter rates of STG and ANI
were 0.0199 and 0.0597 respectively.
If the alpha value is set at 0.1, significant difference was detected
between the baseline and present quarters in both encounter rates of STG and
ANI.
3.5.57
For the comparison
between the baseline period and the cumulative quarters in impact phase (i.e.
first seven quarters of the impact phase being assessed), the p-value for the
differences in average dolphin encounter rates of STG and ANI were 0.0037 and
0.0013 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).
3.5.58
The AFCD monitoring data
during June to August 2014 has been reviewed by the dolphin specialist, and no
dolphin was sighted from 173.90 km of survey effort on primary lines in NEL
during the same quarter (a lone dolphin was sighted in NEL off-effort though
during AFCD monitoring survey in August 2014). This review has confirmed that the very
low occurrence of dolphins reported by the HKLR03 monitoring survey in summer
2014 in NEL is accurate.
3.5.59
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.
3.5.60
All dolphin protective
measures are fully and properly implemented in accordance with the EM&A Manual.
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.
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 25
June 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
(June 2014)
|
Monitoring Station
|
Easting (m)
|
Northing (m)
|
Surface Level
|
Easting (m)
|
Northing (m)
|
Surface Level
|
(mPD)
|
(mPD)
|
S1
|
810291.160
|
816678.727
|
0.950
|
810291.158
|
816678.724
|
1.003
|
S2
|
810958.272
|
815831.531
|
0.864
|
810958.292
|
815831.548
|
0.951
|
S3
|
810716.585
|
815953.308
|
1.341
|
810716.591
|
815953.335
|
1.449
|
S4
|
811221.433
|
816151.381
|
0.931
|
811221.436
|
816151.390
|
1.031
|
Table 3.9 Comparison
of measurement
|
Comparison of measurement
|
Remarks and Recommendation
|
Monitoring Station
|
Easting (m)
|
Northing (m)
|
Surface Level
(mPD)
|
S1
|
-0.002
|
-0.003
|
0.053
|
Within tolerance, no
significant change
|
S2
|
0.020
|
0.017
|
0.087
|
Level continuously increased
|
S3
|
0.005
|
0.027
|
0.078
|
Level continuously increased
|
S4
|
0.003
|
0.009
|
0.100
|
Level continuously increased
|
3.6.2
This measurement result was generally and relatively higher than the baseline
measurement at S2, S3 and S4. The mudflat level is continuously increased. For
S1 showed that the level has increased within tolerance and their sea bed depth would not be considered as
significant change.
Water
Quality Monitoring
3.6.3
The mudflat monitoring covered water quality
monitoring data. Reference was made
to the water quality monitoring data of the representative water quality
monitoring station (i.e. SR3) as in the EM&A Manual. The water quality monitoring location
(SR3) is shown in Figure 2.1.
3.6.4 Impact
water quality monitoring in San Tau (monitoring station SR3) was conducted in June 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)
|
02-Jun-14
|
9.26
|
3.5
|
3.95
|
8.67
|
1.9
|
3.15
|
04-Jun-14
|
7.74
|
3.25
|
3.30
|
7.70
|
1.30
|
3.45
|
06-Jun-14
|
8.63
|
3.15
|
4.10
|
8.46
|
2.05
|
4.25
|
09-Jun-14
|
6.29
|
1.90
|
4.00
|
5.89
|
4.40
|
6.50
|
11-Jun-14
|
5.92
|
1.55
|
6.05
|
5.74
|
4.60
|
6.55
|
13-Jun-14
|
8.09
|
4.25
|
5.15
|
8.18
|
9.90
|
6.75
|
16-Jun-14
|
5.72
|
5.80
|
3.35
|
5.55
|
4.15
|
5.75
|
18-Jun-14
|
6.85
|
4.75
|
3.00
|
6.41
|
2.85
|
3.50
|
20-Jun-14
|
8.04
|
6.90
|
5.90
|
7.11
|
5.60
|
4.35
|
23-Jun-14
|
5.71
|
8.45
|
4.90
|
6.22
|
8.20
|
5.80
|
25-Jun-14
|
5.72
|
4.60
|
3.80
|
6.16
|
6.05
|
3.15
|
27-Jun-14
|
5.64
|
7.05
|
3.80
|
5.91
|
18.65
|
3.95
|
30-Jun-14
|
5.78
|
5.80
|
3.90
|
5.51
|
5.15
|
4.55
|
Average
|
6.87
|
4.69
|
4.25
|
6.73
|
5.75
|
4.75
|
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 June 2014 (totally 6
sampling days between 1st and 16th June 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 13th (for TC3
and ST) and 16th (for TC1 and TC2) June 2014. The weather was sunny
and hot on both survey days.
Seagrass
Beds
3.6.8
An active search method was conducted for seagrass bed monitoring by two
experienced surveyors in every sampling zone. During the search period, any
accessible and potential area would be investigated for any seagrass beds
within 2-3 hours of low tide period. Once seagrass bed was found, the species,
estimated area, estimated coverage percentage and respective GPS coordinate
were recorded. A photographic record was taken for future investigation. The
seagrass beds surveys were conducted on 13th (for TC3 and ST) and 16th
(for TC1 and TC2) June 2014. The weather was sunny and hot on both survey days.
Intertidal
Soft Shore Communities
3.6.9 The intertidal soft shore
community surveys were conducted in low tide period on 1st (for ST),
2nd (for TC3), 14th (for TC2) and 15th June
2014 (for TC1). At each sampling zone, three 100 m horizontal transects were laid at high tidal level (H: 2.0 m above C.D.), mid
tidal level (M: 1.5 m above C.D.) and low tidal level (L: 1.0 m above C.D.). Along every horizontal transect, ten random quadrats (0.5 m x 0.5m) were placed.
3.6.10
Inside a quadrat, any visible epifauna were collected
and were in-situ identified to the
lowest practical taxonomical resolution. Whenever possible a hand core sample (10 cm internal diameter ´ 20 cm depth) of sediments was collected in the quadrat. The core sample was gently washed through a sieve of mesh size 2.0 mm in-situ. Any
visible infauna were collected and identified. Finally the top 5 cm surface
sediments was dug for visible infauna in the quadrat regardless of hand core
sample was taken.
3.6.11
All collected fauna were
released after recording except some tiny individuals that are too small to be identified on site. These
tiny individuals were taken to laboratory for identification under dissecting microscope.
3.6.12
The taxonomic classification
was conducted in accordance to the following references: Polychaetes: Fauchald (1977), Yang and Sun (1988); Arthropods: Dai and Yang (1991), Dong (1991);
Mollusks: Chan and Caley (2003), Qi (2004).
Data
Analysis
3.6.13
Data collected from direct search and core
sampling was pooled in every quadrat for data analysis. Shannon-Weaver
Diversity Index (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.
In general, Carcinoscorpius rotundicauda was found in all sampling zones (TC1: 24 ind., TC2: 1 ind., TC3: 22 ind., ST: 30 ind.) while Tachypleus
tridentatus was found in sampling zones TC3 (11 ind.) and ST (44 ind.) only. All individuals were found on either fine sand
or soft mud substratum. Grouping
was observed from both species while the group
size ranged 2-8 individuals.
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 6.0 ind. hr-1
person-1 (mean prosomal width: 46.96 mm), 0.3 ind. hr-1 person-1 (36.19 mm), 5.5 ind. hr-1 person-1 (28.46 mm), 5.0 ind. hr-1 person-1 (52.47 mm) at TC1, TC2, TC3 and ST respectively. According to Li (2008), the prosomal width of recorded individuals ranged 10.67¡Ð84.84 mm that was about 1.6-9.8 years
old. For
Tachypleus tridentatus, the search record was 2.8 ind. hr-1 person-1 (43.75 mm) and 7.3 ind.
hr-1 person-1 (51.57 mm) at TC3 and ST respectively. The
prosomal
width of recorded individuals ranged
28.14¡Ð73.08 mm that was about 3.6¡V8.5 years old.
3.6.16
Besides, 18 and 3 marked individuals of Tachypleus tridentatus had been recorded in
previous surveys conducted in Sep. 2013 and Mar. 2014 respectively. 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.
3.6.17
The artificial bred individuals were 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 in the past one year. The artificially released
individuals were no longer distinguishable from the natural population without
the specific chip sensor. No marked individual was found in this survey. Hence
the survey data collected would possibly cover both natural population and
artificially bred individuals.
3.6.18
Figure 3.2 and 3.3 of Appendix O shows the changes of number of individuals, mean prosomal width and search record of
horseshoe crab 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 in active season. In contrast, much lower search record was found in other sampling zones
especially TC2 (2 ind. in Sep. 2013, 1 ind. in Mar. 2014 and 1 ind. in Jun.
2014 only). 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, other sampling zones were not suitable
for nursery of horseshoe crab especially TC2. Possible factors were less area
of suitable substratum (especially TC1) and higher human disturbance (TC1, TC2
and TC3: 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
three 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 individuals of Carcinoscorpius rotundicauda were found
after Mar. 2014.
3.6.20 During the survey period from
Sep. 2012 to Jun 2014, the search record of horseshoe crab declined obviously
during dry season especially December (Figures 3.2 and 3.3 of Appendix O).
Furthermore no individual was found in 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. In this survey (Jun. 2014), more individuals were
recorded due to larger size (mean prosomal width 28.46-52.47 mm) and higher
activity.
3.6.22
For Tachypleus tridentatus, sharp increase of
number of individuals was recorded in ST with wet season (from Mar. 2013 (15
ind.), Jun. 2013 (59 ind.) to Sep. 2013 (94 ind.)). 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. Similar pattern
might be recorded in this year of survey.
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 Jun. 2014, the size of major population (50% records between upper and lower quartile) increased
clearly. The prosomal
width increased from 30-40 mm to 45-60 mm. For Tachypleus tridentatus, a consistent growing
trend was observed for the major population from Dec. 2012 to Jun. 2014. The
prosomal width increased from 10-20 mm to 40-60 mm.
The present survey was the seventh time of sampling 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
3.6.24 Table 3.3 of Appendix O show the
records of seagrass beds survey at every sampling zone. Two species of seagrass Halophila ovalis and Zostera japonica were recorded in ST only. In general the number of patches and area of Halophila ovalis were
obviously higher (Table 3.4 of Appendix O). For Halophila
ovalis, the area of highest density consisted of one large and one medium
patches on sandy substratum beside the mangrove vegetation at tidal
level 2 m above C.D. (Figure 3.5(A) of Appendix O). The estimated total seagrass
area was about
469.7 m2 with vegetation coverage 70-90% and smaller leaves. Dry season was its reproductive period while flowers could be observed in Dec. (Figure 3.6 of Appendix O).
3.6.25 Since
Sep. 2013, seasonal recruitment and spreading of Halophila
ovalis were
occurring in ST. Numerous small patches were found on soft mud at tidal level
between 0.5 m and 1.5 m above C.D.. In Mar. 2014, 31 small to medium patches
were recorded (variable area 1-72 m2 per patch, vegetation coverage
40-80% per patch). 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 (Figure
3.5(B) of Appendix O). It was generally grouped into 4 large areas (1116.3
¡V 2442.6 m2) of seagrass beds characterized of patchy distribution,
variable vegetable coverage (40-80%) and smaller leaves.
3.6.26 Four small patches of Zostera
japonica were found within the long strand of Halophila
ovalis. (Figure 3.5 of Appendix O).The
estimated area ranged 0.5-25.7 m2 while the
estimated coverage was
about 40-85%.
3.6.27 Figure 3.7 of Appendix O shows the changes of estimated total area of seagrass beds at ST along the
sampling months. For Halophila ovalis, the total area and estimated coverage increased gradually from Sep.
2012 to Mar. 2014. It showed that the seagrass was in scattered patches on the shore
during dry season of 2012. Then it grew larger and became numerous patches of
varying sizes during 2013. Until Jun. 2014, the total seagrass bed area
increased sharply due to merging of the patches. However the vegetation was in
patchy distribution with highly variable coverage. It was still doubt that
these patches would survive from the natural heat stress, grazing and storm in
the coming hottest period (Jun to Sep 2014).
3.6.28 For Zostera japonica, it
was not recorded in the 1st and 2nd surveys of monitoring
programme. Seasonal recruitment of few patches was found in Mar. 2013. Then the
patch size increased and merged gradually with the warmer climate from Mar. to
Jun. 2013. However the patch size decreased sharply and remained similar from
Sep. 2013 to Mar. 2014. Until Jun. 2014, the patch size increased obviously
again with warmer climate.
3.6.29 The present survey was the sevenh
time of sampling of the EM&A programme during the construction period. Based on the results, impacts of the HKLR project could not be
detected on seagrass considering the factor of natural, seasonal variation. In case, abnormal phenomenon (e.g. rapid
reduction of seagrass patch size, abnormal change of leave colour) is
observed, it would be reported as soon as possible.
Intertidal
Soft Shore Communities
3.6.30
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.
3.6.31 The distribution of substratum types varied among tidal levels and sampling zones. At TC1, even distribution (50%) of ¡¥Gravels and
Boulders¡¦ and ¡¥Sands¡¦ was recorded at high
tidal level. High
percentage of ¡¥Gravels and Boulders¡¦ (90%) was recorded at mid tidal level. Higher percentage of ¡¥Soft mud¡¦ (60%) were
recorded at low tidal level followed by ¡¥Sands¡¦ (20%) and ¡¥Soft mud¡¦ (20%). At TC2, 60% ¡¥Sands¡¦ and 30%
¡¥Soft mud¡¦ were recorded at high tidal level.
Higher percentage of ¡¥Soft mud¡¦ (40-70%) were recorded at mid and low tidal
levels followed by ¡¥Sands¡¦ (30%). At TC3, ¡¥Sands¡¦ (100%) was recorded only at high tidal level. ¡¥Sands¡¦ (60%) and ¡¥Soft mud¡¦ (40%) were
recorded only at mid tidal level. ¡¥Gravels and Boulders¡¦ was the major substratum type (80%) at low tidal
level. At ST, Gravels and Boulders¡¦ (100%) was
the major substratum at high and mid tidal levels. ¡¥Soft mud¡¦ (60%) was mainly recorded
at low tidal level followed by ¡¥Sands¡¦ (20%) and ¡¥Gravels and Boulders¡¦ (20%).
3.6.32 There was neither consistent
vertical nor horizontal zonation pattern of substratum type all sampling zones. In
general, ¡¥Gravels and Boulders¡¦ and ¡¥Sands¡¦ were usually observed at high and mid tidal levels. However
¡¥Soft mud¡¦ was mainly observed at low tidal level. Such
heterogeneous variation
should be caused by different hydrology (e.g. wave in different direction and
intensity) received by the four sampling zones.
3.6.33 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 17896 individuals were recorded. Mollusks
were significantly the most abundant phylum (total individuals 17439, density 581
ind. m-2, relative abundance 97.4%). The second abundant group was arthropods (210 ind.,
7 ind. m-2, 1.2%). The third abundant group was annelids (160 ind., 5 ind. m-2,
0.9%). Relatively
other phyla were very low in abundances (£1 ind. m-2, relative abundance £0.2%). Moreover, the most diverse phylum was mollusks (45 taxa)
followed by arthropods (15 taxa)
and annelids (11 taxa). The
taxa of other phyla
were relatively less (1-2 taxa). The complete list of collected specimens is
provided in Annex III of Appendix O.
3.6.34
Table 3.7 of Appendix O shows the number of individual, relative abundance and density of each phylum at every sampling zone The results were similar
among the four sampling zones. In general, mollusks were the most dominant
phylum (no. of individuals: 3191-6625
ind., relative abundance 95.1-98.7%).
For TC1, TC3 and ST, arthropods were the second abundant phylum (27-58 ind., 0.7-1.4%) although the number of individuals was significantly lower than that
of mollusks. Annelids were the third abundant
phylum (14-39 ind., 0.4-1.0%). For TC2, annelids (76 ind., 2.3%) and arthropods (74 ind., 2.2%) were
similar in abundances. Relatively, other phyla were low
in abundance among the
four sampling zones (< 1%).
3.6.35
Table 3.8 of Appendix O lists the
abundant species (relative abundance >10%) in every sampling zone. In TC1, gastropod Batillaria multiformis was
clearly abundant (321-323 ind. m-2, relative abundance 49-63%) at high and mid tidal levels (major substrata: ¡¥Gravels and Boulders¡¦
& ¡¥Sands¡¦) while other taxa were less in densities. Gastropod Cerithidea
cingulata (79
ind. m-2, 15%) was the second abundant taxon at high tidal
level. Gastropods Cerithidea djadjariensis (110 ind. m-2, 17%) and Monodonta
labio (74 ind. m-2, 11%) were the second and third abundant taxa
respectively at mid tidal level. At low tidal level (major substratum: ¡¥Soft
mud¡¦), gastropods Batillaria zonalis (75 ind. m-2, 17%), Cerithidea djadjariensis (64 ind. m-2, 15%) and rock oyster Saccostrea cucullata (68 ind. m-2, 16%, attached on boulders) were even and moderately abundant at low
tidal levels.
3.6.36
At TC2, gastropods Cerithidea djadjariensis (363 ind. m-2, 52%) and Cerithidea cingulata (210 ind. m-2, 30%) were highly abundant at high tidal level (major substratum: ¡¥Sands¡¦). At mid and low tidal levels (major substrata: ¡¥Soft mud¡¦ &
¡¥Sands¡¦), gastropod Cerithidea djadjariensis was still the most abundant taxon
but the mean densities were much lower (126-135 ind.
m-2, 32-53%). Rock oyster Saccostrea cucullata was the second abundant taxon (72 ind. m-2, 18% attached on boulders) at mid tidal level. Gastropod Batillaria
zonalis were
relatively less in densities (41-44 ind. m-2, 10-18%) at mid and low tidal levels.
3.6.37 At TC3,
gastropod Batillaria multiformis was highly abundant (810 ind. m-2, 62%) at
high tidal level (major substratum: ¡¥Sands¡¦) followed by less abundant
gastropods Cerithidea djadjariensis (302 ind. m-2, 23%) and Cerithidea cingulata (144 ind. m-2, 11%). At mid tidal level (major substrata: ¡¥Sands¡¦
& ¡¥Soft mud¡¦), the density of gastropod Batillaria
multiformis
declined sharply (62
ind. m-2, 10%) and became the third abundant taxon. The
gastropods Cerithidea djadjariensis (284 ind. m-2, 47%) and Cerithidea cingulata (172 ind. m-2, 29%) became the first and second abundant taxa
although their densities were similar. At low tidal level (major substratum: ¡¥Gravels and Boulders¡¦), rock oyster Saccostrea
cucullata (212 ind. m-2, 27%) and
gastropod Batillaria multiformis (206 ind. m-2, 27%) were
more abundant followed by gastropod Monodonta labio (168 ind. m-2, 22%).
3.6.38 At ST,
gastropod Batillaria multiformis
was highly abundant (332 ind. m-2,
50%) at high tidal level (major substratum:
¡¥Gravels and Boulders¡¦) followed by much less abundant gastropod Monodonta labio (83 ind. m-2, 12%) and
rock oyster Saccostrea cucullata (77 ind. m-2, 12%). At
mid tidal level (major substratum: ¡¥Gravels and Boulders¡¦), gastropod Monodonta labio (134 ind. m-2, 21%) and
rock oyster Saccostrea cucullata (131 ind. m-2, 21%) were higher in abundances. Other less
abundant taxa were gastropods Batillaria multiformis (97 ind. m-2, 15%) and Cellana toreuma (88 ind. m-2, 14%). At low tidal level (major substratum: ¡¥Soft
mud¡¦), gastropods Cerithidea djadjariensis (55 ind. m-2, 23%), Batillaria
zonalis (51 ind. m-2, 22%), Batillaria bornii (25 ind. m-2, 11%) and rock oyster Saccostrea
cucullata (43 ind. m-2, 18%, attached on boulders) were abundant taxa at
lower densities relative to that at high and mid tidal levels.
3.6.39 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: 5665 ind., relative abundance 31.7%), Cerithidea djadjariensis (4013 ind., 22.4%) and Cerithidea cingulata (1831 ind., 10.2%) were the most commonly
occurring species on sandy substratum. Moreover rock oyster Saccostrea cucullata (1827 ind., 10.2%) and gastropod Monodonta
labio (1374 ind., 7.7%) were commonly occurring species inhabiting gravel and boulders substratum.
3.6.40
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, the mean number of species was similar (9-14
spp. 0.25 m-2). The mean densities in TC3 (600-1309 ind. m-2) was higher than
that in TC1 (431-655 ind. m-2), ST (236-665 ind. m-2) and
TC2 (253-692 ind. m-2). The mean H¡¦
(1.60) and J (0.66) in ST were
relatively higher than that in TC1, TC2 and TC3 (H¡¦: 1.22-1.39, J:
0.55-0.62).
3.6.41 Across the tidal levels, there was
no difference for the mean number of species. Higher mean densities were found
at high and mid tidal levels. Higher H¡¦
and J were observed at mid and low
tidal levels in TC1, TC2 and TC3. But both values were higher at high and mid
tidal levels in ST.
3.6.42 Figure 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 significant
temporal change of any biological parameters was observed. All the parameters
were under slight and natural fluctuation with the seasonal variation.
3.6.43
The present survey was the seventh survey of the EM&A programme
during the construction period. Based on the results,
impacts of the HKLR project were not
detected on intertidal soft shore community. In case, abnormal phenomenon (e.g. large reduction of fauna densities and species number) is observed, it would be reported as soon as
possible.
3.7
Solid and Liquid Waste Management Status
3.7.1
The Contractor registered with EPD as a Chemical
Waste Producer on 12 July 2012 for the Contract. Sufficient numbers of
receptacles were available for general refuse collection and sorting.
3.7.2
The summary of waste flow table is detailed in Appendix K.
3.7.3
The Contractor was reminded that chemical waste
containers should be properly treated and stored temporarily in designated
chemical waste storage area on site in accordance with the Code of 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 followed:
Air Quality
4.1.2
For air quality, there were no
Action and Limit Level exceedances for 1-hr TSP and 24-hr TSP during the
reporting period.
Noise
4.1.3
There were no Action and Limit Level exceedances for noise during
daytime on normal weekdays of the reporting period.
Water Quality
4.1.4 During the reporting period, two Action Level exceedances of suspended solid
level were recorded. Ten Action Level exceedances of dissolved oxygen level
were recorded. No Action
and Limit Level exceedance of turbidity was 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
4.1.5
There
were two Action Level exceedances of dolphin monitoring for the quarterly monitoring data (June ¡V August 2014). According to the
contractor¡¦s information, the
marine activities undertaken for HKLR03 during the quarter of June 2014 to
August 2014 included stone platform construction, reclamation, stone column
installation, band drain installation, excavation of stone platform, surcharge
activities, construction of seawall and temporary drainage diversion.
4.1.6
There is no evidence showing the current AL
non-compliances directly related to the construction works
of HKLR03, although the generally increased amount of vessel traffic in NEL during
the impact phase has been partly contributed by HKLR03 works since October
2012. It should also be noted that
reclamation work under HKLR03 (adjoining the Airport Island) situates in waters
which has rarely been used by dolphins in the past, and the working vessels
under HKLR03 have been travelling from source to destination in accordance with
the Marine Travel Route to minimize impacts on Chinese White Dolphin. In addition, the contractor will
implement proactive mitigation measures such as avoiding anchoring at Marine
Department¡¦s designated anchorage site ¡V Sham Shui Kok Anchorage (near Brothers
Island) as far as practicable.
4.1.7 All dolphin protective measures
are fully and properly implemented in accordance with the EM&A Manual. The Contractor will continue to provide training to 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.
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
|
--
|
--
|
--
|
--
|
--
|
--
|
--
|
--
|
0
|
0
|
Limit Level
|
--
|
--
|
--
|
--
|
--
|
--
|
--
|
--
|
0
|
0
|
IS(Mf)6
|
Action Level
|
--
|
9 July 2014
|
--
|
--
|
--
|
--
|
11 Aug 2014
|
--
|
1
|
1
|
Limit Level
|
--
|
--
|
--
|
--
|
--
|
--
|
--
|
--
|
0
|
0
|
IS7
|
Action Level
|
--
|
--
|
--
|
--
|
--
|
--
|
--
|
--
|
0
|
0
|
Limit Level
|
--
|
--
|
--
|
--
|
--
|
--
|
--
|
--
|
0
|
0
|
IS8
|
Action Level
|
--
|
27 June 2014
|
--
|
--
|
--
|
--
|
--
|
--
|
0
|
1
|
Limit Level
|
--
|
--
|
--
|
--
|
--
|
|
--
|
--
|
0
|
0
|
IS(Mf)9
|
Action Level
|
--
|
--
|
--
|
--
|
--
|
--
|
--
|
--
|
0
|
0
|
Limit Level
|
--
|
--
|
--
|
--
|
--
|
--
|
--
|
--
|
0
|
0
|
IS10
|
Action Level
|
15 Aug 2014
|
15 Aug 2014
|
15 Aug 2014
|
15 Aug 2014
|
--
|
--
|
--
|
--
|
2
|
2
|
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
|
15 Aug 2014
|
15 Aug 2014
|
15 Aug 2014
|
15 Aug 2014
|
--
|
--
|
--
|
13 Aug 2014
|
2
|
3
|
Limit Level
|
--
|
--
|
--
|
--
|
--
|
--
|
--
|
--
|
0
|
0
|
SR10A
|
Action Level
|
--
|
--
|
--
|
--
|
--
|
--
|
--
|
--
|
0
|
0
|
Limit Level
|
--
|
--
|
--
|
--
|
--
|
--
|
--
|
--
|
0
|
0
|
SR10B
|
Action Level
|
--
|
--
|
--
|
--
|
--
|
--
|
--
|
--
|
0
|
0
|
Limit Level
|
--
|
--
|
--
|
--
|
--
|
--
|
--
|
--
|
0
|
0
|
Total
|
Action
|
2
|
4
|
2
|
2
|
0
|
0
|
1
|
1
|
12**
|
Limit
|
0
|
0
|
0
|
0
|
0
|
0
|
0
|
0
|
0**
|
Notes:
S: Surface;
M: Mid-depth;
** The total exceedances.
4.2
Summary of Environmental Complaint, Notification of
Summons and Successful Prosecution
4.2.1
There were no environmental complaints received during this
reporting period. The details
of cumulative statistics of environmental complaints are provided in Appendix
N.
4.2.2
No notification of
summons and prosecution was received during the reporting period.
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
provide vehicle washing bay at site exits of S8/S9.
¡± The Contractor was reminded to
provide an impervious cover when piling at S11.
¡± The Contractor was reminded to
clean the oily films at S11.
¡± The Contractor was reminded to
provide water spray regularly on the haul road/unpaved road at S15 and S25.
¡± The Contractor was reminded to
provide water spray to breaking activity at N1.
¡± The Contractor was reminded to
connect with the waste water treatment facilities at S25.
¡± The Contractor was reminded to
provide a proper cover at the top and 3 sides for the cement mixing plant at S9
and S11.
¡± The Contractor was reminded to
cover the cement bags at S15.
¡± The Contractor was reminded to
remove the construction equipment adjacent to the trees and fencing off the
tree.
¡± The Contract was reminded to remove
the stagnant water inside the disused wheel washing bay and H-beam at N4.
¡± The Contractor was reminded to
remove the stagnant water at abutment at N1 and on the ground at N13.
¡± The Contractor was reminded to
fill up the recesses of the concrete block to avoid accumulation of water at
N4.
¡± The Contractor was reminded to
water the dry stockpile material at S13.
¡± The
Contractor was reminded to provide maintenance to the noise barriers at S16.
¡± The Contractor was reminded to enhance
the standard of wheel washing facility at S25.
¡± The Contractor was reminded to
ensure the overlapping length of two pieces of silt-curtain for the vessel
access opening over 150m.
¡± The
Contractor was reminded to provide sandbags along the public road at N13.
¡± The Contractor was reminded to
provide sandbags along the seaside at S7.
¡± The Contractor was reminded to
provide a proper noise enclosure at S23.
¡± The Contractor was reminded to
clean up the oil leakage from excavator at S16.
¡± The Contractor was reminded to
clean up the fill materials at the edge of the barge at vessel of Chung Sheng
308 and Kiu Tak at S7.
¡± The Contractor was reminded to
provide proper drainage system for flood protection at S15.
¡± The Contractor was reminded to
repair the damaged impervious sheet of dump truck at S16.
¡± The Contractor was reminded to
provide drip tray and label to chemical containers at N4, N13, S25 and at
vessel of Chun Ming 83.
¡± The Contractor was reminded to
remove rubbish frequently at S15, N1 and N4.
¡± The Contractor was reminded to
provide the stopper to drip tray to avoid oil leakage at S15 and N4.
¡± The Contractor was reminded to
seal the water barrier at N1.
¡± The Contractor was reminded to
provide sand bags to prevent leakage of muddy water onto the public road at
S11-S15.
¡± The Contractor was reminded to
enclose the gaps between silt curtain and seashore at S16.
¡± The Contractor was reminded to straighten the curved silt curtain.
¡± The Contractor was reminded to repair the damaged cover of the dump truck (number plate: HA196) at
S15.
¡± The Contractor was reminded to
clean up the blocked drainage system at S23.
¡± The Contractor was reminded to
provide maintenance for the emission for Chun Ming 18 at S7.
¡± The Contractor was reminded to
provide proper wheel washing facility at the entrance/exit of N20 and S22.
¡± The Contractor was reminded to
provide maintenance to the damaged hoarding at S11.
¡± The Contractor was reminded to
replace the air filter of vessel Shun Tak 22.
¡± The Contractor was reminded to
stop muddy water discharge from vessel Shun Tak 22.
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 Eighth Quarterly EM&A Report which summarises
the monitoring results and audit findings of the EM&A programme during the
reporting period from 1 June to 31 August 2014.
Air Quality
5.3.2
For air quality, there were no
Action and Limit Level exceedances for 1-hr TSP and 24-hr TSP recorded during
the reporting period.
Noise
5.3.3
For construction noise, there
were no Action Level and Limit Level exceedances during the reporting
period.
Water Quality
5.3.4
During the reporting period, two Action Level
exceedances of suspended solid level were recorded. Ten Action Level
exceedances of dissolved oxygen level were recorded. No Limit Level exceedance
of suspended solid level and dissolved oxygen level were recorded. No Action and Limit Level exceedance of turbidity
was recorded.
Dolphin
5.3.5
There were two Action Level exceedances of dolphin monitoring for the quarterly monitoring
data (June ¡V August 2014).
5.3.6
During this quarter of dolphin
monitoring, no adverse impact from the activities of this construction project
on Chinese White Dolphins was noticeable from general observations.
5.3.7
Although dolphins rarely
occurred in the area of HKLR03 construction in the past and during the baseline
monitoring period, it is apparent that dolphin usage has been significantly
reduced in NEL in 2012 - 2014, and many individuals have shifted away from the
important habitat around the Brothers Islands.
5.3.8
It 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 situation.
Mudflat
-Sedimentation Rate
5.3.9
This measurement result was generally and relatively higher than the
baseline measurement at S2, S3 and S4. The mudflat level is continuously
increased. For S1 showed that the level has increased within tolerance and their sea bed depth would not be considered as
significant change.
5.3.10 Impact
water quality monitoring in San Tau (monitoring station SR3) was conducted in June 2014.
The monitoring parameters included dissolved oxygen (DO), turbidity and
suspended solids (SS).
Mudflat - Ecology
5.3.11
The June 2014 survey was the seventh time of sampling of the EM&A programme during the construction
period. Based on the results, impacts of the HKLR
project were not detected on horseshoe crabs, seagrass
and intertidal soft shore community.
Environmental
Site inspection and Audit
5.3.12
Environmental site inspection
was carried out on 4, 11, 18 and 27 June 2014, 2, 9, 16,
25 and 30 July
2014 and 6, 13, 20 and 29 August 2014. Recommendations on remedial actions were given to the Contractors
for the deficiencies identified during the site inspections.
5.3.13
There were no environmental
complaints received during this reporting period.
5.3.14
No notification of summons and
prosecution was received during the reporting period.