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.
9 (Sep 2014 to Nov 2014)
22 May 2015
Revision 1
Main Contractor Designer
Executive Summary
The Hong Kong-Zhuhai-Macao Bridge (HZMB) Hong
Kong Link Road (HKLR) serves to connect the HZMB Main Bridge at the Hong Kong Special
Administrative Region (HKSAR) Boundary and the HZMB Hong Kong Boundary Crossing
Facilities (HKBCF) located at the north eastern waters of the Hong Kong
International Airport (HKIA).
The HKLR project has been separated into two
contracts. They are Contract No.
HY/2011/03 Hong Kong-Zhuhai-Macao Bridge Hong Kong Link Road-Section between
Scenic Hill and Hong Kong Boundary Crossing Facilities (hereafter referred to
as the Contract) and Contract No. HY/2011/09 Hong Kong-Zhuhai-Macao Bridge Hong
Kong Link Road-Section between HKSAR Boundary and Scenic Hill.
China State Construction Engineering (Hong Kong)
Ltd. was awarded by Highways Department as the Contractor to undertake the
construction works of Contract No. HY/2011/03. The main works of the Contract include
land tunnel at Scenic Hill, tunnel underneath Airport Road and Airport Express
Line, reclamation and tunnel to the east coast of the Airport Island, at-grade
road connecting to the HKBCF and highway works of the HKBCF within the Airport
Island and in the vicinity of the HKLR reclamation. The Contract is part of the HKLR Project
and HKBCF Project, these projects are considered to be ¡§Designated Projects¡¨,
under Schedule 2 of the Environmental Impact Assessment (EIA) Ordinance (Cap
499) and EIA Reports (Register No. AEIAR-144/2009 and AEIAR-145/2009) were
prepared for the Project. The
current Environmental Permit (EP) EP-352/2009/D for HKLR and EP-353/2009/H for
HKBCF were issued on 22 December 2014 and 19 January 2015, respectively. These
documents are available through the EIA Ordinance Register. The construction
phase of Contract was commenced on 17 October 2012.
BMT Asia Pacific Limited has been appointed by
the Contractor to implement the Environmental Monitoring & Audit (EM&A)
programme for the Contract in accordance with the Updated EM&A Manual for
HKLR (Version 1.0) and will be providing environmental team services to the
Contract.
This is the ninth 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 September 2014 to 30 November 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
|
September 2014
|
October 2014
|
November 2014
|
Air
Quality
|
1-hr TSP
|
AMS5: 4,
10, 18, 22, 26 and 30
AMS6: 4,
10, 16, 22, 26 and 30
|
6, 10,
16, 22 and 28
|
3, 7, 13,
19 and 25
|
24-hr TSP
|
AMS5: 2,
10, 12, 18, 24 and30
AMS6: 2,
8, 17, 18, 24 and 30
|
3, 9, 15,
21, 27 and 31
|
AMS5: 6,
12, 18, 24
AMS6: 6,
12, 18, 24 and 28
|
Noise
|
4, 10,
18, 22 and 30
|
6, 16, 22
and 28
|
3, 13, 19
and 25
|
Water
Quality
|
1, 3, 5,
8, 10, 12, 15, 17, 19, 22, 24, 26 and 29
|
1, 3, 6,
8, 10, 13, 15, 17, 20, 22, 24, 27, 29 and 31
|
3, 5, 7,
10, 12, 14, 17, 19, 21, 24, 26 and 28
|
Chinese
White Dolphin
|
2,11,19
and 22
|
7, 13, 16
and 23
|
4, 10, 12
and 18
|
Mudflat
Monitoring (Ecology)
|
6, 7, 8,
9, 20 and 21
|
-
|
-
|
Mudflat
Monitoring (Sedimentation rate)
|
6
|
-
|
-
|
Site Inspection
|
3, 10, 17
and 26
|
3, 8, 15,
22 and 31
|
5, 12, 19
and 28
|
Due to the power interruption on 8 September 2014, the 24-hr air monitoring undertaken at AMS5 was less than 24
hours. Therefore, the 24-hr TSP
monitoring result on 8 September 2014 was considered invalid and the 24 hrs dust monitoring was rescheduled
from 8 September 2014 to 10 September 2014.
Due to the motor failure of the high volume
sampler, the 24-hr air monitoring result at AMS6 on 12 September 2014 was considered invalid. The 24 hrs dust
monitoring was rescheduled from 12 September 2014 to 17 September 2014.
As Strong Wind Signal
No. 3 was hoisted by the Hong Kong Observatory (HKO) on 15 September 2014, the water quality monitoring for mid-ebb tide of 15 September 2014 was cancelled for safety reason. Also, the
dolphins monitoring was rescheduled from 15 September 2014 to 19 September 2014.As Tropical Cyclone Warning Signal No. 8 was hoisted on 16 September 2014, the 1-hr TSP monitoring at AMS5 and noise
monitoring at NMS5 were rescheduled from 16 September to 18 September 2014.As 1 and 2 October 2014 were bank holidays, 1-hr dust monitoring at
AMS5 and AMS6 were rescheduled to 30 September 2014.
Due to boat
availability issue, the dolphins monitoring schedule was rescheduled from 17
October 2014 to 16 October 2014, from 21 October 2014 to 23 October 2014, from
6 November 2014 to 10 November 2014 and from 14 November 2014 to 18 November
2014.
Due to malfunction of
HVS at AMS5 on 28 November 2014, the 24-hr air monitoring undertaken at AMS5 was less than
24
hours. The 24-hr TSP monitoring result obtained on 28 November 2014 was considered invalid
and the 24-hr dust monitoring
was rescheduled from 28 November 2014 to 2 December 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
|
2
|
0
|
Noise
|
Leq
(30 min)
|
0
|
0
|
Water
Quality
|
Suspended
solids level (SS)
|
9
|
3
|
Turbidity
level
|
0
|
0
|
Dissolved
oxygen level (DO)
|
0
|
0
|
Dolphin
Monitoring
|
Quarterly
Analysis (Sep to Nov 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/D for HKLR and EP-353/2009/H for HKBCF were issued on 22 December
2014 and 19 January 2015, respectively. These documents are available through
the EIA Ordinance Register. The construction
phase of Contract was commenced on 17 October
2012. Figure 1.1 shows
the project site boundary.
1.1.5
This is the ninth 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
September 2014 to 30 November 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 installation
¡P
Sheet piling and jet grouting
¡P
Excavation and lateral support works for Scenic Hill Tunnel (Cut &
Cover Tunnel
|
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
|
Airport Road
|
¡P
Pipe piling Cofferdam Works for HAT West
Cut & Cover tunnel
|
Kwo Lo Wan /Airport Road
|
¡P
Works for diversion of Airport Road and Kwo
Lo Wan Road
|
Kwo Lo Wan /Airport Road /Airport
Express Line
|
¡P
Utilities detection
|
Kwo Lo Wan Road
|
¡P
Excavation and lateral support works at
shaft 3 extension north shaft
|
2.1
Summary of
EM&A Requirements
2.1.1
The EM&A programme requires environmental
monitoring of air quality, noise, water quality, dolphin monitoring and mudflat
monitoring as specified in the approved EM&A Manual.
2.1.2
A summary of Impact EM&A requirements is
presented in Table 2.1. The
locations of air quality, noise and water quality monitoring stations are shown
as in Figure
2.1. The transect line
layout in Northwest and Northeast Lantau Survey Areas is presented in Figure
2.2.
Table 2.1 Summary
of Impact EM&A Requirements
Environmental
Monitoring
|
Description
|
Monitoring
Station
|
Frequencies
|
Remarks
|
Air Quality
|
1-hr TSP
|
AMS 5 & AMS 6
|
At least 3 times every 6 days
|
While the highest dust impact was expected.
|
24-hr TSP
|
At least once every 6 days
|
--
|
Noise
|
Leq (30mins),
L10 (30mins) and
L90 (30mins)
|
NMS5
|
At least once per week
|
Daytime on normal weekdays
(0700-1900 hrs).
|
Water Quality
|
¡P Depth
¡P Temperature
¡P Salinity
¡P Dissolved
Oxygen (DO)
¡P Suspended
Solids (SS)
¡P DO
Saturation
¡P Turbidity
¡P pH
|
¡P Impact
Stations:
IS5, IS(Mf)6, IS7, IS8, IS(Mf)9 & IS10,
¡P Control/Far
Field Stations:
CS2 & CS(Mf)5,
¡P Sensitive
Receiver Stations:
SR3, SR4, SR5, SR10A & SR10B
|
Three times per week
during mid-ebb and mid-flood tides (within ¡Ó 1.75 hour of the predicted time)
|
3
(1 m below water surface,
mid-depth and 1 m above sea bed, except where the water depth is less than 6
m, in which case the mid-depth station may be omitted. Should the water depth be less than 3
m, only the mid-depth station will be monitored).
|
Dolphin
|
Line-transect
Methods
|
Northeast Lantau survey
area and Northwest Lantau survey area
|
Twice per month
|
--
|
Mudflat
|
Horseshoe crabs, seagrass beds, intertidal soft shore communities,
sedimentation rates and water quality
|
San Tau and Tung Chung Bay
|
Once every 3 months
|
--
|
2.2.1
Table 2.2 presents
the Action and Limit Levels for the 1-hour TSP, 24-hour TSP and noise level.
Table 2.2 Action
and Limit Levels for 1-hour TSP, 24-hour TSP and Noise
Environmental Monitoring
|
Parameters
|
Monitoring Station
|
Action Level
|
Limit Level
|
Air
Quality
|
1-hr TSP
|
AMS 5
|
352 µg/m3
|
500 µg/m3
|
AMS 6
|
360 µg/m3
|
24-hr TSP
|
AMS 5
|
164 µg/m3
|
260 µg/m3
|
AMS 6
|
173 µg/m3
|
Noise
|
Leq
(30 min)
|
NMS 5
|
When one documented complaint is received
|
75 dB(A)
|
2.2.2
The Action and Limit
Levels for water quality monitoring are given as in Table 2.3.
Table 2.3 Action
and Limit Levels for Water Quality
Parameter
(unit)
|
Water
Depth
|
Action
Level
|
Limit
Level
|
Dissolved Oxygen (mg/L)
|
Surface and Middle
|
5.0
|
4.2 except 5 for Fish
Culture Zone
|
Bottom
|
4.7
|
3.6
|
Turbidity (NTU)
|
Depth average
|
27.5 or 120% of upstream
control station¡¦s turbidity at the same tide of the same day;
The action level has been
amended to ¡§27.5 and 120% of upstream control station¡¦s turbidity at the same
tide of the same day¡¨ since 25 March 2013.
|
47.0 or 130% of turbidity
at the upstream control station at the same tide of same day;
The limit level has been
amended to ¡§47.0 and 130% of turbidity at the upstream control station at the
same tide of same day¡¨ since 25 March 2013.
|
Suspended Solid (SS)
(mg/L)
|
Depth average
|
23.5 or 120% of upstream
control station¡¦s SS at the same tide of the same day;
The action level has been
amended to ¡§23.5 and 120% of upstream control station¡¦s SS at the same tide of
the same day¡¨ since 25 March 2013.
|
34.4 or 130% of SS at the
upstream control station at the same tide of same day and 10mg/L for Water
Services Department Seawater Intakes;
The limit level has been
amended to ¡§34.4 and 130% of SS at the upstream control station at the same
tide of same day and 10mg/L for Water Services Department Seawater Intakes¡¨
since 25 March 2013
|
Notes:
(1) Depth-averaged
is calculated by taking the arithmetic means of reading of all three depths.
(2) For DO,
non-compliance of the water quality limit occurs when monitoring result is
lower that the limit.
(3) For SS
& turbidity non-compliance of the water quality limits occur when
monitoring result is higher than the limits.
(4) The change
to the Action and limit Levels for Water Quality Monitoring for the EM&A
works was approved by EPD on 25 March 2013. Therefore, the amended Action and Limit
Levels are applied for the water monitoring results obtained on and after 25
March 2013.
2.2.3
The Action and Limit
Levels for dolphin monitoring are shown in Tables
2.4 and 2.5.
Table 2.4 Action
and Limit Level for Dolphin Impact Monitoring
|
North
Lantau Social Cluster
|
NEL
|
NWL
|
Action Level
|
STG < 70% of baseline
&
ANI < 70% of baseline
|
STG < 70% of baseline
&
ANI < 70% of baseline
|
Limit Level
|
STG < 40% of baseline
&
ANI < 40% of baseline
|
Remarks:
(1)
STG means quarterly average encounter rate of
number of dolphin sightings.
(2)
ANI means quarterly average encounter rate of
total number of dolphins.
(3)
For North Lantau Social Cluster, AL will be
trigger if either NEL or NWL fall below the criteria; LL will be triggered if
both NEL and NWL fall below the criteria.
Table 2.5 Derived
Value of Action Level (AL) and Limit Level (LL)
|
North
Lantau Social Cluster
|
NEL
|
NWL
|
Action Level
|
STG < 4.2 & ANI < 15.5
|
STG < 6.9 & ANI
< 31.3
|
Limit Level
|
(STG < 2.4 & ANI
< 8.9) and (STG < 3.9 & ANI < 17.9)
|
Remarks:
(1)
STG means quarterly average encounter rate of
number of dolphin sightings.
(2)
ANI means quarterly average encounter rate of
total number of dolphins.
(3)
For North Lantau Social Cluster, AL will be
trigger if either NEL or NWL fall below the criteria; LL will be triggered if
both NEL and NWL fall below the criteria.
2.3.1 The Event Actions Plans for air quality, noise, water quality and
dolphin monitoring are annexed in Appendix D.
2.4.1
Environmental
mitigation measures for the contract were recommended in the approved EIA
Report. Appendix E lists the recommended mitigation measures and the
implementation status.
3
Environmental Monitoring and Audit
3.1
Implementation of
Environmental Measures
3.1.1
In response to the site audit findings, the
Contractor carried out corrective actions.
Details of site audit findings and the corrective actions during the
reporting period are presented in Appendix
F.
3.1.2
A summary of the Implementation Schedule of
Environmental Mitigation Measures (EMIS) is presented in Appendix E.
3.1.3
Regular marine travel route for
marine vessels were implemented properly in accordance to the submitted plan
and relevant records were kept properly.
3.1.4
Dolphin Watching Plan was
implemented during the reporting period.
No dolphins inside the silt curtain were observed. The relevant records were kept
properly.
3.2.1
The monitoring results for 1-hour TSP and
24-hour TSP are summarized in Tables 3.1 and 3.2
respectively. Detailed impact air quality monitoring results and relevant graphical
plots are presented in Appendix G.
Table 3.1 Summary
of 1-hour TSP Monitoring Results During the Reporting Period
Reporting
Period
|
Monitoring
Station
|
Average (mg/m3)
|
Range (mg/m3)
|
Action Level (mg/m3)
|
Limit Level (mg/m3)
|
September 2014
|
AMS5
|
45
|
8-117
|
352
|
500
|
AMS6
|
38
|
16-77
|
360
|
October 2014
|
AMS5
|
146
|
73-274
|
352
|
AMS6
|
138
|
92-188
|
360
|
November 2014
|
AMS5
|
164
|
70-305
|
352
|
AMS6
|
145
|
81-181
|
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)
|
September 2014
|
AMS5
|
44
|
15-93
|
164
|
260
|
AMS6
|
92
|
40-132
|
173
|
October 2014
|
AMS5
|
75
|
36-116
|
164
|
AMS6
|
146
|
72-233
|
173
|
November 2014
|
AMS5
|
80
|
35-123
|
164
|
AMS6
|
104
|
69-151
|
173
|
3.2.2
For AMS5, no Action and Limit Level exceedances of 1-hr TSP and 24-hr
TSP were recorded at AMS 5
during the reporting period.
3.2.3
For AMS6, no Action
and Limit Level exceedances of 1-hr TSP level and no Limit Level exceedances of 24-hr TSP were recorded during the reporting period. An Action Level exceedance
of 24-hr TSP level was recorded on 15 and 27 October 2014, respectively.
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)
|
September 2014
|
NMS5
|
56
|
53-57
|
When one documented complaint is received
|
75
|
October 2014
|
60
|
58-62
|
November 2014
|
58
|
56-60
|
3.3.2
There were no Action and Limit Level exceedances for noise during
daytime on normal weekdays of the
reporting period.
3.3.3
Major noise sources during the noise monitoring
included construction activities of the Contract and nearby traffic noise.
3.4.1
Impact water quality monitoring was conducted at
all designated monitoring stations during the reporting period. Impact water quality monitoring results and
relevant graphical plots are provided in
Appendix I.
3.4.2
During the reporting period, nine Action Level
exceedances and three Limit Level exceedances of suspended solid level were
recorded. No Action and Limit Level exceedance of dissolved oxygen level were
recorded. No Action
and Limit Level exceedances of turbidity
were recorded.
3.4.3
Water quality impact sources during the water
quality monitoring were the construction activities of the Contract, nearby
construction activities by other parties and nearby operating vessels by other
parties.
Data
Analysis
3.5.1
Distribution Analysis ¡V The
line-transect survey data was integrated with the Geographic Information System
(GIS) in order to visualize and interpret different spatial and temporal
patterns of dolphin distribution using sighting positions. Location data of dolphin groups were
plotted on map layers of Hong Kong using a desktop GIS (ArcView© 3.1) to
examine their distribution patterns in details. The dataset was also stratified into
different subsets to examine distribution patterns of dolphin groups with
different categories of group sizes, young calves and activities.
3.5.2
Encounter rate analysis ¡V
Encounter rates of Chinese White Dolphins (number of on-effort sightings per
100 km of survey effort, and total number of dolphins sighted on-effort per 100
km of survey effort) were calculated in NEL and NWL survey areas in relation to
the amount of survey effort conducted during each month of monitoring survey.
Dolphin encounter rates were calculated in two ways for comparisons with the
HZMB baseline monitoring results as well as to AFCD long-term marine mammal
monitoring results.
3.5.3
Firstly, for the comparison
with the HZMB baseline monitoring results, the encounter rates were calculated
using primary survey effort alone, and only data collected under Beaufort 3 or
below condition would be used for encounter rate analysis. The average encounter rate of sightings
(STG) and average encounter rate of dolphins (ANI) were deduced based on the
encounter rates from six events during the present quarter (i.e. six sets of
line-transect surveys in North Lantau), which was also compared with the one
deduced from the six events during the baseline period (i.e. six sets of
line-transect surveys in North Lantau).
3.5.4
Secondly, the encounter rates
were calculated using both primary and secondary survey effort collected under
Beaufort 3 or below condition as in AFCD long-term monitoring study. The encounter rate of sightings and
dolphins were deduced by dividing the total number of on-effort sightings and
total number of dolphins (ANI) by the amount of survey effort for the entire
quarterly period (September¡V November 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 September to November
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 892.88 km
of survey effort was collected, with 97.1% 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, 343.71 km and 549.17 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 644.60 km, while the effort on secondary lines was 248.28
km. Both survey effort conducted on
primary and secondary lines were considered as on-effort survey data. A summary
table of the survey effort is shown in Annex
I of Appendix
J.
3.5.12
During the six sets of monitoring surveys
in September to November 2014, a total of 24 groups of 93 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 two on-effort sightings were made on secondary
lines. In this quarterly period,
all dolphin groups were sighted in NWL, while none of them were sighted in NEL.
A summary table of the dolphin sightings is shown in Annex II of Appendix J.
Distribution
3.5.13
Distribution of dolphin sightings made
during monitoring surveys in September to November 2014 was shown in Figure 1 of Appendix J.
Similar to recent quarters, the majority of dolphin sightings made in the
present quarter were concentrated in the northwestern end of the North Lantau region, with higher concentration around
Lung Kwu Chau (Figure 1 of Appendix J). A few other sightings were scattered
around Sha Chau and to the north of the airport platform. No dolphin sighting was made in NEL in
the present quarter.
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 (September to November 2014) was compared to the
one during the baseline monitoring period (September to November 2011). In the present quarter, dolphins have
completely avoided the NEL region, which was in stark contrast to their
frequent occurrence around the Brothers
Islands and in the
vicinity of HKBCF reclamation site during the baseline period (Figure 1 of Appendix J).
The nearly complete abandonment of NEL region by the dolphins has been
consistently recorded in the past seven quarters, which have resulted in
extremely low dolphin encounter rates in this area.
3.5.16
In NWL survey area, dolphin occurrence was
also very 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 near Sha Chau and Black Point during the
baseline period than during the present impact monitoring period (Figure 1 of Appendix J). Notably, 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 the dolphins were not sighted there
at all during the present impact phase period.
3.5.17
Another comparison in dolphin distribution
was made between the two quarterly periods of autumn months in 2013 and 2014
was also made (Figure 2 of Appendix J). Among the two autumn periods, no dolphin
sighting was made in NEL in the autumn of 2014, while there were two sightings
made there in the autumn of 2013.
Moreover, a lot more dolphin sightings were made in the middle and
western portions of North Lantau waters
(especially between Black Point and Lung Kwu Chau, as well as around Sha Chau)
in the autumn of 2013 than in the autumn of 2014. The comparison indicated that dolphin
usage in North Lantau waters was further
diminished in autumn of 2014 from the same period in the previous year.
Encounter Rate
3.5.18
For the three-month study period in
September, October and November 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 (Sep ¡VNov 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 (2 & 11 Sep 2014)
|
0.00
|
0.00
|
Set 2 (19 & 22 Sep 2014)
|
0.00
|
0.00
|
Set 3 (7 & 13 Oct 2014)
|
0.00
|
0.00
|
Set 4 (16 & 23 Oct 2014)
|
0.00
|
0.00
|
Set 5 (4 & 10 Nov 2014)
|
0.00
|
0.00
|
Set 6 (12 & 18 Nov 2014)
|
0.00
|
0.00
|
Northwest Lantau
|
Set 1 (2 & 11 Sep 2014)
|
5.72
|
28.58
|
Set 2 (19 & 22 Sep 2014)
|
4.34
|
18.80
|
Set 3 (7 & 13 Oct 2014)
|
13.13
|
42.67
|
Set 4 (16 & 23 Oct 2014)
|
0.00
|
0.00
|
Set 5 (4 & 10 Nov 2014)
|
4.60
|
24.54
|
Set 6 (12 & 18 Nov 2014)
|
2.84
|
8.53
|
Table 3.5 Comparison
of Average Dolphin Encounter Rates between Reporting Period (Sep ¡V Nov 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
|
0.00
|
6.00 ¡Ó 5.05
|
0.00
|
22.19 ¡Ó 26.81
|
Northwest Lantau
|
5.10 ¡Ó 4.40
|
9.85 ¡Ó 5.85
|
20.52 ¡Ó 15.10
|
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)
3.5.19
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
4.18 sightings and 16.17 dolphins per 100 km of survey effort respectively,
while the encounter rates of sightings (STG) and dolphins (ANI) in NEL were
both nil.
3.5.20
In NEL, the average dolphin encounter rates (both STG and ANI) in the
present three-month impact monitoring period were zero, and such low occurrence
of dolphins in NEL have been consistently recorded in the past seven quarters (Table 3.6).
3.5.21
It is a serious concern that dolphin occurrence in NEL in the seven
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 eighth consecutive quarters being assessed that have triggered the
Action Levels 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.
3.5.22
Moreover, the average dolphin encounter rates (STG and ANI) in NWL
during the present impact phase monitoring period were also much lower
(reductions of 48.2% and 54.1% 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 (Table 3.7).
Table
3.6 Comparison of Average
Dolphin Encounter Rates in Northeast Lantau Survey Area from All Quarters of
Impact Monitoring Period and Baseline Monitoring Period (Sep ¡V Nov 2011)
|
Encounter rate (STG)
(no. of on-effort dolphin sightings per 100 km of survey effort)
|
Encounter rate (ANI)
(no. of dolphins from
all on-effort sightings per 100 km of survey effort)
|
September-November
2011 (Baseline)
|
6.00 ¡Ó 5.05
|
22.19 ¡Ó 26.81
|
December
2012-February 2013 (Impact)
|
3.14 ¡Ó 3.21
|
6.33 ¡Ó 8.64
|
March-May 2013
(Impact)
|
0.42 ¡Ó 1.03
|
0.42 ¡Ó 1.03
|
June-August 2013
(Impact)
|
0.88 ¡Ó 1.36
|
3.91 ¡Ó 8.36
|
September-November
2013 (Impact)
|
1.01 ¡Ó 1.59
|
3.77 ¡Ó 6.49
|
December
2013-February 2014 (Impact)
|
0.45 ¡Ó 1.10
|
1.34 ¡Ó 3.29
|
March-May 2014
(Impact)
|
0.00
|
0.00
|
June-August 2014
(Impact)
|
0.42 ¡Ó 1.04
|
1.69 ¡Ó 4.15
|
September-November
2014 (Impact)
|
0.00
|
0.00
|
Note:
The encounter rates deduced from the baseline monitoring period have been
recalculated based only on survey effort and on-effort sighting data made along
the primary transect lines under favourable conditions.
Table 3.7 Comparison of Average Dolphin Encounter Rates in Northwest Lantau
Survey Area from All Quarters of Impact Monitoring Period and Baseline
Monitoring Period (Sep ¡V Nov 2011)
|
Encounter
rate (STG)
(no. of on-effort
dolphin sightings per 100 km of survey effort)
|
Encounter
rate (ANI)
(no. of dolphins from all on-effort sightings per 100 km of survey
effort)
|
September-November 2011 (Baseline)
|
9.85 ¡Ó 5.85
|
44.66 ¡Ó 29.85
|
December 2012-February 2013 (Impact)
|
8.36 ¡Ó 5.03
|
35.90 ¡Ó 23.10
|
March-May 2013 (Impact)
|
7.75 ¡Ó 3.96
|
24.23 ¡Ó 18.05
|
June-August 2013 (Impact)
|
6.56 ¡Ó 3.68
|
27.00 ¡Ó 18.71
|
September-November 2013 (Impact)
|
8.04 ¡Ó 1.10
|
32.48 ¡Ó 26.51
|
December 2013-February 2014 (Impact)
|
8.21 ¡Ó 2.21
|
32.58 ¡Ó 11.21
|
March-May 2014 (Impact)
|
6.51 ¡Ó 3.34
|
19.14 ¡Ó 7.19
|
June-August 2014 (Impact)
|
4.74 ¡Ó 3.84
|
17.52 ¡Ó 15.12
|
September-November 2014 (Impact)
|
5.10 ¡Ó 4.40
|
20.52 ¡Ó 15.10
|
Note: The encounter rates deduced from the
baseline monitoring period have been recalculated based only on survey effort
and on-effort sighting data made along the primary transect lines under
favourable conditions.
3.5.23
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).
3.5.24
For the comparison between the baseline period
and the present quarter (eighth quarter of the impact phase being assessed),
the p-value for the differences in average dolphin encounter rates of STG and
ANI were 0.0222 and 0.0662 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.
3.5.25
For the comparison between the baseline period
and the cumulative quarters in impact phase (i.e. first eight quarters of the
impact phase being assessed), the p-value for the differences in average
dolphin encounter rates of STG and ANI were 0.0019 and 0.0006
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).
3.5.26
As indicated in both dolphin distribution
patterns and encounter rates, dolphin usage has been significantly reduced in
NEL waters in the present quarterly period, and such low occurrence has been
consistently documented in previous quarters. This raises serious concern, as the
decline in dolphin usage could possibly link to the HZMB-related construction
activities in NEL waters.
3.5.27
To ensure the continuous usage of NEL waters by
the dolphins, every possible measure should be implemented by the contractors
and relevant authorities to minimize all disturbances to the dolphins, as 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).
3.5.28
It should be noted that dolphin usage in NWL
have also been diminished progressively in the past few quarters (Table 3.7), and such downward trend
should be closely monitored, as the potential impacts of HZMB-related works on
the dolphins may have been extended to the entire North Lantau region.
Group
Size
3.5.29
Group size of Chinese White Dolphins ranged from
one to 13 individuals per group in North Lantau
region during September ¡V November 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 (Sep ¡V Nov 2014) and Baseline Monitoring
Period (Sep¡V Nov 2011)
|
Average Dolphin Group Size
|
Reporting Period
|
Baseline Monitoring Period
|
Overall
|
3.88 ¡Ó 2.69 (n = 24)
|
3.72 ¡Ó 3.13 (n = 66)
|
Northeast Lantau
|
0.00
|
3.18 ¡Ó 2.16 (n = 17)
|
Northwest Lantau
|
3.88 ¡Ó 2.69 (n = 24)
|
3.92 ¡Ó 3.40 (n = 49)
|
3.5.30
The average dolphin group sizes in the entire North Lantau region as
well as in NWL waters during September ¡V November 2014 were similar to the ones
recorded during the three-month baseline period (Table 3.8). Sixteen of
the 24 groups were composed of 1-4 individuals only, while there was only one
dolphin group with more than 10 individuals.
3.5.31
Distribution of dolphins with larger group sizes (five individuals or
more per group) during the present quarter is shown in Figure 3 of Appendix J, with comparison to the one in baseline period. During the autumn of 2014, distribution
of the majority of larger dolphin groups were concentrated near Lung Kwu Chau (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).
3.5.32
Notably, none of the larger dolphin groups were sighted near the HKLR03
reclamation site in the present monitoring period (Figure 3 of Appendix J).
Habitat
Use
3.5.33
From September to November 2014, the most heavily utilized habitats by
Chinese White Dolphins mainly concentrated around Lung Kwu Chau (Figures 4a and 4b of Appendix J). None of the grids in NEL
recorded the presence of dolphins in the present quarter. Moreover, all grids near HKLR03/HKBCF
reclamation sites, HKLR09 or TMCLKL alignment did not record any presence of
dolphins during on-effort search in the present quarterly period.
3.5.34
However, it should be emphasized that the amount of survey effort
collected in each grid during the three-month period was fairly low (6-12 units
of survey effort for most grids), and therefore the habitat use pattern derived
from the three-month dataset should be treated with caution. A more complete picture of dolphin habitat
use pattern will be presented when more survey effort for each grid will be
collected throughout the impact phase monitoring programme.
3.5.35
When compared with the habitat use patterns during the baseline period,
dolphin usage in NEL was dramatically different from the present impact
monitoring period (Figure 5 of Appendix J). During the baseline
period, nine grids between Siu Mo To and Shum Shui Kok recorded moderately high
to high dolphin densities, which was in stark contrast to complete absence of
dolphins during the present impact phase period (Figure 5 of Appendix J).
3.5.36
The density patterns between the baseline and impact phase monitoring
periods were also different in NWL, with higher dolphin usage around Sha Chau,
near Black Point, to the west of the airport, as well as between Pillar Point
and airport platform during the baseline period (Figure 5 of Appendix J).
3.5.37
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
3.5.38
During the three-month study period, only four unspotted juveniles (UJ)
were sighted in NWL survey areas.
These young calves comprised of 4.3% of all animals sighted, which was
lower than the percentage recorded during the baseline monitoring period
(6.8%).
3.5.39
All four young calves were sighted around Lung Kwu Chau (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 the four 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
3.5.40
A total of three dolphin sightings were associated with feeding and
socializing activities respectively during the three-month study period. The percentage of sightings associated
with feeding activities during the present quarter (8.3%) was lower than the
one recorded during the baseline period (11.6%). On the contrary, the percentage of
socializing activities during the present impact phase monitoring period (4.2%)
was slightly lower than the one recorded during the baseline period
(5.4%). One group of five dolphins
was also engaged in traveling activity during the present quarter.
3.5.41
Distribution of dolphins engaged in feeding, socializing and traveling
activities during the present three-month period is shown in Figure 7 of Appendix J. The three sightings
associated with feeding and traveling activities all occurred to the north of
Lung Kwu Chau, while the lone sighting associated with socializing activity was
located to the north of the airport (Figure
7 of Appendix J). Distribution of dolphin
sightings associated with these activities during the impact phase was very different
from the distribution pattern of these activities during the baseline period (Figure 7 of Appendix J).
3.5.42
During the three-month period, none of the 24 dolphin groups was found
to be associated with an operating fishing vessels in North
Lantau waters. The
extremely rare events of fishing boat association in the present and previous
quarters were consistently found, and were likely related to the recent trawl
ban being implemented in December 2012 in Hong Kong
waters.
Photo-identification
and Individual Range Use
3.5.43
From September to November
2014, over 2,000 digital photographs of Chinese White Dolphins were taken
during the impact phase monitoring surveys for the photo-identification work.
3.5.44
In total, 26 individuals
sighted 49 times altogether were identified (see summary table in Annex III
of Appendix
J
and
photographs of
identified individuals in Annex IV
of Appendix
J). All
of these 49 re-sightings were made in NWL.
3.5.45
The majority of identified individuals were sighted only once or twice
during the three-month period, with the exception of five individuals (NL202,
NL214, NL233, NL286 and WL05) being sighted thrice and two individuals (NL48
and NL182) being sighted four times.
3.5.46
Five of these 26 individuals were also sighted in West Lantau waters
during the HKLR09 monitoring surveys for the same three-month period, showing
their movement between North and West Lantau regions.
3.5.47
Five recognized females (NL104, NL182, NL202, NL233 and NL256) were
accompanied with their calves during their re-sightings. Some of these mothers were frequently
sighted with their calves throughout the HKLR03 impact phase monitoring period
since October 2012.
Individual
range use
3.5.48
Ranging patterns of the 26
individuals identified during the three-month study period were determined by
fixed kernel method, and are shown in Annex
V of Appendix J.
3.5.49
All 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.
3.5.50
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. NL136, NL182, NL259; 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.
3.5.51
On the other hand, there were a
few 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.
NL259). 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
3.5.52
There were two Action Level exceedances of dolphin
monitoring for the quarterly monitoring data (September ¡V November 2014). According to the Contractor¡¦s information, the marine activities undertaken for HKLR03 during
the quarter of September 2014 to November 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-compliance 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.
3.5.53
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).
3.5.54
For the comparison
between the baseline period and the present quarter (eighth quarter of the
impact phase), the p-value for the differences in average dolphin encounter
rates of STG and ANI were 0.0222 and 0.0662 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.
3.5.55
For the comparison
between the baseline period and the cumulative quarters in impact phase (i.e.
first eight quarters of the impact phase), the p-value for the differences in
average dolphin encounter rates of STG and ANI were 0.0019 and 0.0006
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).
3.5.56
The AFCD monitoring data
during September to November 2014 has been reviewed by the dolphin specialist,
and no dolphin was sighted from 108.93 km of survey effort on primary lines in
NEL during the same quarter. This
review has confirmed that the extremely low occurrence of dolphins reported by
the HKLR03 monitoring survey in autumn 2014 in NEL is accurate.
3.5.57
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.
3.5.58
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.
3.5.59
A
meeting was held on 9 December 2014 with attendance of ENPO, Resident Site
Staff (RSS), Environmental Team (ET) and dolphin specialist for Contract No.
HY/2010/02, RSS, ET, dolphin specialist and main Contractor for Contract No.
HY/2011/03. The discussion/recommendation as recorded in the minutes of the
meeting, which might be relevant to HKLR03 Contract are summarized below.
3.5.60
It
was concluded that the HZMB works is one of the contributing factors affecting
the dolphins. It was also concluded the contribution of impacts due to the HZMB
works as a whole (or individual marine contracts) cannot be quantified nor
separate from the other stress factors.
3.5.61
It
was reminded that the ETs shall keep reviewing the implementation status of the
dolphin related mitigation measures and remind the contractor to ensure the
relevant measures were fully implemented.
3.5.62
It
was recommended that the marine works of HZMB projects should be completed as
soon as possible so as to reduce the overall duration of impacts and allow the
dolphins population to recover as early as possible.
3.5.63
It
was also recommended that the marine works footprint (e.g., reduce the size of
peripheral silt curtain) and vessels for the marine works should be reduced as
much as possible, and vessels idling / mooring in other part of the North
Lantau shall be avoided whenever possible. The team for HY/2010/02 advised that
the contractor was already using large capacity sand barge so as to reduce the
number of vessel traffics, and had already submitted a proposal to resize the
peripheral silt curtain.
3.5.64
It
was suggested that the protection measures (e.g., speed limit control) for the
proposed Brothers Island Marine Park (BMP) shall be brought forward as soon as
possible before its establishment so as to provide a better habitat for dolphin
recovery. It was noted that under the Regular Marine Travel Route Plan, the
contractors have committed to reduce the vessel speed in BMP.
3.5.65
There
was a discussion on exploring possible further mitigation measures, for
example, controlling the underwater noise. It was noted that the EIA reports
for the projects suggested several mitigation measures, all of which have been
implemented.
3.6
Mudflat Monitoring Results
Sedimentation
Rate Monitoring
3.6.1
The baseline sedimentation rate monitoring was
in September 2012 and impact sedimentation rate monitoring was undertaken on 6
September 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
(September 2014)
|
Monitoring Station
|
Easting (m)
|
Northing (m)
|
Surface Level
|
Easting (m)
|
Northing (m)
|
Surface Level
|
(mPD)
|
(mPD)
|
S1
|
810291.160
|
816678.727
|
0.950
|
810291.165
|
816678.754
|
1.030
|
S2
|
810958.272
|
815831.531
|
0.864
|
810958.261
|
815831.522
|
0.940
|
S3
|
810716.585
|
815953.308
|
1.341
|
810716.593
|
815953.320
|
1.450
|
S4
|
811221.433
|
816151.381
|
0.931
|
811221.424
|
816151.402
|
1.146
|
Table 3.9 Comparison
of measurement
|
Comparison of measurement
|
Remarks and Recommendation
|
Monitoring Station
|
Easting (m)
|
Northing (m)
|
Surface Level
(mPD)
|
S1
|
0.005
|
0.027
|
0.080
|
Level continuously increased
|
S2
|
-0.011
|
-0.009
|
0.076
|
Level continuously increased
|
S3
|
0.008
|
0.011
|
0.109
|
Level continuously increased
|
S4
|
-0.009
|
0.054
|
0.215
|
Level continuously increased
|
3.6.2
This measurement result was generally and relatively higher than the
baseline measurement at S1, S2, S3 and S4. The mudflat level is continuously
increased.
Water
Quality Monitoring
3.6.3
The mudflat monitoring covered water quality
monitoring data. Reference was made
to the water quality monitoring data of the representative water quality
monitoring station (i.e. SR3) as in the EM&A Manual. The water quality monitoring location
(SR3) is shown in Figure
2.1.
3.6.4 Impact
water quality monitoring in San Tau (monitoring station SR3) was conducted in September 2014.
The monitoring parameters included dissolved oxygen (DO), turbidity and
suspended solids (SS).
3.6.5 The
Impact monitoring result for SR3 were extracted and summarised below:
Table 3.10 Impact
Water Quality Monitoring Results (Depth Average)
Date
|
Mid Ebb Tide
|
Mid Flood Tide
|
DO (mg/L)
|
Turbidity
(NTU)
|
SS (mg/L)
|
DO (mg/L)
|
Turbidity
(NTU)
|
SS (mg/L)
|
01-Sep-14
|
6.48
|
6.50
|
5.20
|
6.01
|
7.35
|
6.50
|
03-Sep-14
|
6.17
|
3.45
|
1.95
|
7.36
|
3.15
|
3.70
|
05-Sep-14
|
5.96
|
5.35
|
4.50
|
8.40
|
5.80
|
6.80
|
08-Sep-14
|
6.19
|
7.50
|
10.95
|
6.48
|
7.30
|
6.45
|
10-Sep-14
|
5.49
|
25.05
|
27.50
|
5.44
|
9.10
|
8.55
|
12-Sep-14
|
5.76
|
17.05
|
17.10
|
5.71
|
12.20
|
12.50
|
15-Sep-14*
|
-
|
-
|
-
|
5.65
|
5.25
|
5.65
|
17-Sep-14
|
6.00
|
5.85
|
6.20
|
6.50
|
6.45
|
6.30
|
19-Sep-14
|
6.28
|
4.30
|
2.60
|
7.18
|
3.05
|
5.20
|
22-Sep-14
|
6.98
|
8.55
|
5.50
|
6.82
|
8.30
|
8.90
|
24-Sep-14
|
6.34
|
9.30
|
8.70
|
6.60
|
8.90
|
9.25
|
26-Sep-14
|
5.78
|
12.35
|
17.50
|
5.88
|
13.40
|
22.05
|
29-Sep-14
|
5.98
|
12.30
|
12.35
|
6.02
|
5.80
|
6.60
|
Average
|
6.12
|
9.80
|
10.00
|
6.46
|
7.39
|
8.34
|
Remark:
* As
Strong Wind Signal No. 3 was hoisted by HKO on 15 September 2014, the water quality monitoring for mid-ebb tide of 15 September 2014 was
cancelled for safety reason.
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 September 2014 (totally 6 sampling days between 6th and 21st September 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 8th (for TC1
and TC2) and 21st (for TC3 and ST) September 2014. The weather was
cloudy and windy on both survey days.
Seagrass
Beds
3.6.8
Active search method was conducted for seagrass bed monitoring
by two experienced surveyors at every sampling zone. During the search period, any
accessible and potential area would be investigated for any seagrass beds
within 2-3 hours in low tide period. Once seagrass
bed was found, the species, estimated area, estimated coverage percentage and respective GPS coordinate were recorded. A photographic
record was taken for
future investigation. The seagrass beds surveys were
conducted on 8th (for TC1 and TC2) and 21st (for TC3 and
ST) September 2014. The weather was cloudy and windy on both survey days.
Intertidal
Soft Shore Communities
3.6.9 The intertidal soft shore
community surveys were conducted in low tide period on 6th (for
TC3), 7th (for ST), 9th (for TC2) and 20 September 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: 21 ind., TC2: 1 ind., TC3: 58 ind., ST: 43 ind.) while Tachypleus
tridentatus was found in sampling zones TC1 (1 ind.), TC3 (11 ind.) and ST (4 ind.). Most of individuals were found on fine sand
substratum followed by soft mud. Grouping
was observed from both species while the group
size ranged 2-14 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 5.3 ind. hr-1
person-1 (mean prosomal width: 40.73 mm), 0.3 ind. hr-1 person-1 (45.82 mm), 14.5 ind. hr-1 person-1 (27.81 mm), 10.8 ind. hr-1 person-1 (38.39 mm) at TC1, TC2, TC3 and ST respectively. According to Li (2008), the prosomal width of recorded individuals ranged 15.39¡Ð70.93 mm that was about 2.7-11.3 years
old. For
Tachypleus tridentatus, the search record was 0.3 ind. hr-1 person-1 (30.48 mm), 2.8 ind. hr-1
person-1 (32.48 mm) and 0.7 ind. hr-1 person-1 (49.93 mm) at TC1, TC3 and ST respectively. The prosomal width of
recorded individuals ranged
27.33¡Ð66.74 mm that was about 3.5¡V7.8 years old.
3.6.16
Besides, marked individuals of Carcinoscorpius rotundicauda (2 ind.) and Tachypleus tridentatus (1 ind.) were recorded
in ST in present survey. Similar findings had been recorded in previous surveys
conducted in Sep. 2013 and Mar. 2014. All of them were released through a
conservation programme conducted by Prof. Paul Shin (Department of Biology and
Chemistry, The City University of Hong Kong (CityU)). It was a re-introduction
trial of artificial bred horseshoe crab juvenile at selected sites. So that the
horseshoe crabs population might be restored in the natural habitat. Through a
personal conversation with Prof. Shin, about 100 individuals were released in the
sampling zone ST on 20 June 2013. All of them were marked with color tape and
internal chip detected by specific chip sensor.
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. The survey data collected would possibly cover both
natural population and artificially bred individuals. Besides, the three marked
individuals in present survey were possibly released in the new round of the
programme.
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. But the highest search record was
found in TC3 in the present survey. In contrast, much lower search record was
found in other sampling zones especially TC2 (2 ind. in Sep. 2013, 1 ind. in
Mar., Jun. and Sep. 2014). There was no spatial difference of horseshoe crab
size (prosomal width) among the sampling zones.
3.6.19 It was obvious that ST was an important nursery ground
for horseshoe crab especially newly hatched individuals due to larger area of
suitable substratum (fine sand or soft mud) and less human disturbance (far
from urban district). Relatively, 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, 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. From Mar. to Sep. 2014, more individuals were recorded
due to larger size and higher activity.
3.6.22
For Tachypleus tridentatus, sharp increase of
number of individuals was recorded in ST with wet season (from Mar. to Sep.
2013). According to a personal conversation with Prof. Shin (CityU), his
monitoring team had recorded similar increase of horseshoe crab population
during wet season. It was believed that the suitable ambient temperature
increased its conspicuousness. However similar pattern was not recorded during
the period of this year. The number of individuals increased in Mar. and Jun.
2014 followed by a rapid decline in Sep. 2014. Apart from natural mortality,
migration from nursery soft shore to subtidal habitat was another possible
cause. Since the mean prosomal width of Tachypleus tridentatus continued to grow and reached about 50 mm in this year. Most of the
individuals might have reached a suitable size strong enough to forage in
subtidal habitat.
3.6.23
Figure 3.4 of Appendix O shows the changes of prosomal width of horseshoe crab Carcinoscorpius rotundicauda and Tachypleus tridentatus in ST where was
regarded as an important nursery ground. As mentioned above, Carcinoscorpius rotundicauda was rarely found between Sep. 2012 and Dec. 2013 hence the data were
limiting. From Mar. to Sep. 2014, the size of major population (50% records between upper and
lower quartile) fluctuated between 30-40 mm and 45-60 mm. Such fluctuation should be due to
variable encounter rate influenced by weather. For Tachypleus tridentatus, a consistent growing
trend was observed for the major population from Dec. 2012 to Sep. 2014. The
prosomal width increased from 10-20 mm to 40-60 mm. As mentioned, the large individuals might have reached a suitable size for migrating from the
nursery soft shore to subtidal habitat.
3.6.24
The present survey was the eighth time of the EM&A programme during
the construction period. Based on the results, impact
of the HKLR project could not be detected on horseshoe crabs considering the
factor of natural, seasonal variation. In case, abnormal phenomenon (e.g. very few numbers of horseshoe crab individuals in warm weather, large number of dead individuals on the shore)
is observed, it would be reported as soon as possible.
Seagrass Beds
3.6.25 Table 3.3 of Appendix
O show the records of seagrass beds survey at every sampling zone. 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 significantly
higher (Table
3.4 of Appendix O). For Halophila ovalis, the area of highest coverage
consisted of one large and one medium patch 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 305.9 m2 with vegetation
coverage 85%. (Figure 3.6 of Appendix O).
3.6.26 However, the largest seagrass bed of Halophila ovalis located on soft mud in patchy distribution between
1.0 m and 1.5 m above C.D. (Figure
3.5(B) of Appendix
O). Such large area of seagrass bed
was merged by numerous smaller patches recruited seasonally in the past. In
Dec. 2013, flowers could
be observed during its reproductive period (Figure 3.6 of Appendix O). 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. 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. In present survey (Sep. 2014), the seagrass area
declined sharply while there was only one single patch (785.9 m2) recorded in that
mudflat area. But this patch was of higher coverage (70%) and larger leaves.
Besides, Halophila ovalis could be found in other
mud flat area surrounding the single patch. But it was hardly distinguished
into patches due to very low coverage (10-20%) and small leaves.
3.6.27 Two small patches of Zostera japonica were found within the long strand of Halophila ovalis (Figure 3.5 of Appendix O). The estimated
area ranged 0.5-1.6 m2 while the estimated coverage was about 50-55%.
3.6.28 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. In 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. In the present survey (Sep. 2014), the total seagrass area declined
rapidly. The natural heat stress and grazing force were the possible causes
during the hot, wet season (Jun to Sep 2014).
3.6.29 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. In Jun. 2014, the patch size increased obviously again with warmer
climate. Similar to previous year, the patch size decreased again in Sep. 2014.
3.6.30 The present survey was the eighth
survey 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
3.6.31
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.
3.6.32 The distribution of substratum types varied among tidal levels and sampling zones. At TC1, high percentages of ¡¥Gravels and Boulders¡¦ (70-90%) were recorded at all tidal levels while the remaining
substratum type was ¡¥Sands¡¦(10-30%). At TC2, high percentages of ¡¥Sands¡¦ (70-90%) were recorded at high and mid tidal levels followed by ¡¥Soft mud¡¦ (10-30%).
Conversely, high percentage of ¡¥Soft mud¡¦ (70%) was recorded at low tidal level
followed by ¡¥Sands¡¦ (30%). At TC3, high percentages of ¡¥Sands¡¦ (70-80%)
were recorded at high and mid tidal
levels followed by ¡¥Soft mud¡¦ (20-30%). ¡¥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. ¡¥Sands¡¦
(70%) was mainly recorded at low tidal level followed by ¡¥Soft mud¡¦ (20%) and
¡¥Gravels and Boulders¡¦ (10%).
3.6.33 There was neither consistent
vertical nor horizontal zonation pattern of substratum type all sampling zones Such heterogeneous variation should be caused by different hydrology (e.g. wave in
different direction and intensity) received by the four sampling zones.
3.6.34 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 14402 individuals were recorded. Mollusca was significantly the most abundant phylum (total individuals 13923, density 464
ind. m-2, relative abundance 96.7%). The second abundant phylum was Arthropoda (312 ind., 10 ind. m-2,
2.2%). The third and forth abundant
phyla were Annelida (77 ind., 3 ind. m-2, 0.5%) and Sipuncula (63 ind., 2 ind. m-2, 0.4%). Relatively other phyla were very low in
abundances (density £1 ind. m-2, relative abundance £0.1%). Moreover, the most diverse phylum was Mollusca (40 taxa) followed by Arthropoda (16 taxa)
and Annelida (8 taxa). The
taxa of other phyla
were relatively less (1-2 taxa). The complete list of collected specimens is shown in Annex III of Appendix
O.
3.6.35
Table 3.7 of Appendix
O shows the number of individual, relative abundance and density of each phylum in every sampling zone. The results were similar
among the four sampling zones. In general, Mollusca was the most dominant phylum (no. of individuals: 3234-3717 ind., relative abundance 95.3-97.9%). Arthropoda was the
second abundant phylum (61-117 ind., 1.6-3.0%) although
the number of individuals was significantly lower than that of mollusks. For TC2, Annelida was the third abundant phylum (32 ind., 1.0%). Relatively, other phyla were low in abundance among the four sampling zones (< 1%).
3.6.36
Table 3.8 of Appendix
O lists the abundant
species (relative abundance >10%) in every sampling zone. In TC1, gastropod Batillaria multiformis was the
most abundant (173-175 ind. m-2, relative abundance 36-40%) at high and mid tidal levels (major substratum: ¡¥Gravels and Boulders¡¦).
Gastropods Cerithidea cingulata (106 ind. m-2, 25%) and Cerithidea djadjariensis (74 ind. m-2, 17%) were the second and third abundant taxa at
high tidal level. At mid tidal level, the less dominant species were rock oyster Saccostrea
cucullata (102 ind. m-2, 21%, attached
on boulders), gastropods Monodonta
labio (80 ind. m-2, 16%) and Cerithidea
djadjariensis (62 ind. m-2, 13%). At
low tidal level (major substratum: ¡¥Gravels and Boulders¡¦), the dominant
gastropods Monodonta labio (160 ind. m-2, 28%), Batillaria multiformis (102 ind. m-2, 18%) and rock oyster Saccostrea cucullata (144 ind. m-2, 25%) were even in density at low tidal levels.
3.6.37
At TC2, gastropods Cerithidea djadjariensis (331 ind. m-2, 52%) and Cerithidea cingulata (179 ind. m-2, 28%) 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 (53-160 ind.
m-2, 29-31%). Rock oyster Saccostrea cucullata (45-119 ind. m-2, 23-25%) and gastropod Batillaria zonalis (37-60 ind. m-2, 12-20%) were the second and third abundant taxa at mid and low tidal levels.
Gastropod Cerithidea cingulata (56 ind. m-2, 11%) was
the forth abundant at mid tidal levels.
3.6.38 At TC3,
gastropods Cerithidea
djadjariensis (199-227 ind. m-2, 36-42%) and Cerithidea cingulata (153-181 ind.
m-2, 28-33%) were highly abundant at high and mid tidal
levels (major substratum: ¡¥Sands¡¦) followed by less abundant gastropod Batillaria multiformis (74-91 ind. m-2, 14-17%). At low
tidal level
(major substratum: ¡¥Gravels and Boulders¡¦), rock oyster Saccostrea cucullata (212 ind. m-2, 45%) was the most abundant followed by gastropod
Monodonta labio at much lower density (92 ind. m-2,
19%).
3.6.39 At ST
gastropod Batillaria multiformis
was highly abundant (206 ind. m-2,
38%) at high tidal level (major substratum:
¡¥Gravels and Boulders¡¦) followed by much less abundant gastropod Monodonta labio (127 ind. m-2, 23%) and
rock oyster Saccostrea cucullata (66 ind. m-2, 12%). At
mid tidal level (major substratum: ¡¥Gravels and Boulders¡¦), gastropod Monodonta labio (146 ind. m-2, 25%) and
rock oyster Saccostrea cucullata (102 ind. m-2, 17%) were higher in abundances. Other less
abundant taxa were gastropods Cerithidea
djadjariensis (71 ind. m-2, 12%) and Batillaria
multiformis (56 ind. m-2, 10%). At low tidal level (major substratum:
¡¥Sands¡¦), rock oyster Saccostrea cucullata (50 ind. m-2, 22%), gastropods Lunella coronata (42 ind. m-2, 18%), Cerithidea
djadjariensis (37 ind. m-2, 16%) and Batillaria
zonalis (25 ind. m-2, 11%) were abundant taxa at lower densities
relative to that at high and mid tidal levels.
3.6.40 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 Cerithidea
djadjariensis
(total number of individuals: 3189 ind., relative abundance 22.1%), Batillaria multiformis (2398 ind., 16.7%), and Cerithidea cingulata (1958 ind., 13.6%) were the most commonly
occurring species on sandy substratum. In previous surveys, the most dominant
taxon was usually gastropod Batillaria multiformis. Its abundance declined and was replaced by
gastropod Cerithidea djadjariensis in the present survey. Moreover rock oyster Saccostrea
cucullata (2278
ind., 15.8%) and gastropod Monodonta labio (1653 ind., 11.5%) were commonly occurring species inhabiting
gravel and boulders substratum.
3.6.41
Table 3.9 of Appendix
O shows
the mean values of number of species, density, biodiversity index H¡¦ and species evenness J of soft shore communities at every tidal level and in every sampling zone. Among the sampling zones, there
was no clear difference in the mean number of species (7-16 spp. 0.25 m-2)
and densities (182-640 ind. m-2). The mean H¡¦ (1.76) and J (0.74) in ST were relatively higher
than that in TC1, TC2 and TC3 (H¡¦:
1.33-1.44, J: 0.64-0.69).
3.6.42 Across the tidal levels, there
was no consistent difference for the mean number of species and H¡¦ in all sampling zones. In TC1 and
TC3, the mean densities ranged 433-575 ind. m-2 and were similar among
the three tidal levels. In TC2 and ST, the mean densities at high and mid tidal
levels (518-640 ind. m-2) were much higher than that at low tidal
level (182-230 ind. m-2). Higher J
was usually observed at mid and low tidal tidal levels.
3.6.43 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.
3.6.44 The present survey was the eighth
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 AMS5, no Action and Limit Level exceedances of 1-hr TSP and 24-hr
TSP levels were recorded during
the reporting period.
4.1.3
For AMS6, no Action and Limit Level exceedances
of 1-hr TSP and no Limit Level exceedances of 24-hr TSP were recorded during
the reporting period. An Action Level exceedance of 24-hr TSP level was
recorded on 15 and 27 October 2014, respectively
Noise
4.1.4
There were no Action and Limit Level exceedances for noise during
daytime on normal weekdays of the reporting period.
Water Quality
4.1.5 During the reporting period, nine Action Level and three Limit Level exceedances
of suspended solid level were recorded. No Action and Limit level exceedances of
dissolved oxygen level were recorded. No Action
and Limit Level exceedances of turbidity
were recorded.
There were no
specific activities recorded during the monitoring period that would cause any
significant impacts on monitoring results and no leakage of turbid water or any
abnormity or malpractice was observed during the sampling exercise. Therefore, all exceedances were considered as
non-contract related. The detailed numbers of
exceedances recorded during the reporting period at each impact station are summarised in Table 4.1.
Dolphin
4.1.6
There were two Action Level exceedances of
dolphin monitoring for the quarterly monitoring data (September ¡V November 2014). According to the
contractor¡¦s information, the marine activities undertaken for HKLR03 during
the quarter of September 2014 to November 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.
4.1.7
There is no evidence
showing the current AL non-compliance 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.
4.1.8
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.
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
|
--
|
--
|
--
|
--
|
--
|
--
|
10 September 2014
|
--
|
1
|
0
|
IS(Mf)6
|
Action Level
|
--
|
--
|
--
|
--
|
--
|
--
|
--
|
--
|
0
|
0
|
Limit Level
|
--
|
--
|
--
|
--
|
--
|
--
|
--
|
--
|
0
|
0
|
IS7
|
Action Level
|
--
|
--
|
--
|
--
|
--
|
--
|
--
|
--
|
0
|
0
|
Limit Level
|
--
|
--
|
--
|
--
|
--
|
--
|
--
|
--
|
0
|
0
|
IS8
|
Action Level
|
--
|
--
|
--
|
--
|
--
|
--
|
--
|
--
|
0
|
0
|
Limit Level
|
--
|
--
|
--
|
--
|
--
|
|
--
|
--
|
0
|
0
|
IS(Mf)9
|
Action Level
|
--
|
--
|
--
|
--
|
--
|
--
|
--
|
--
|
0
|
0
|
Limit Level
|
--
|
--
|
--
|
--
|
--
|
--
|
--
|
--
|
0
|
0
|
IS10
|
Action Level
|
--
|
--
|
--
|
--
|
--
|
--
|
--
|
13 October 2014
|
0
|
1
|
Limit Level
|
--
|
--
|
--
|
--
|
--
|
--
|
--
|
5 November 2014
|
0
|
1
|
SR3
|
Action Level
|
--
|
--
|
--
|
--
|
--
|
--
|
10 September 2014
|
--
|
1
|
0
|
Limit Level
|
--
|
--
|
--
|
--
|
--
|
--
|
--
|
--
|
0
|
0
|
SR4
|
Action Level
|
--
|
--
|
--
|
--
|
--
|
--
|
--
|
20 October 2014; 5
November 2014
|
0
|
2
|
Limit Level
|
--
|
--
|
--
|
--
|
--
|
--
|
--
|
--
|
0
|
0
|
SR5
|
Action Level
|
--
|
--
|
--
|
--
|
--
|
--
|
--
|
10, 13
October 2014
|
0
|
2
|
Limit Level
|
--
|
--
|
--
|
--
|
--
|
--
|
--
|
6 October 2014
|
0
|
1
|
SR10A
|
Action Level
|
--
|
--
|
--
|
--
|
--
|
--
|
--
|
22 October 2014
|
0
|
1
|
Limit Level
|
--
|
--
|
--
|
--
|
--
|
--
|
--
|
--
|
0
|
0
|
SR10B
|
Action Level
|
--
|
--
|
--
|
--
|
--
|
--
|
--
|
10, 22 October 2014
|
0
|
2
|
Limit Level
|
--
|
--
|
--
|
--
|
--
|
--
|
--
|
--
|
0
|
0
|
Total
|
Action
|
0
|
0
|
0
|
0
|
0
|
0
|
1
|
8
|
9**
|
Limit
|
0
|
0
|
0
|
0
|
0
|
0
|
1
|
2
|
3**
|
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 drip trays and chemical labels for the chemical containers at vessel
Shun Tak 82, chemical containers at N1, N4, N20, S7, S11 and S15-S16.
¡± The Contractor was reminded to
provide drip tray for the water pump at S11.
¡± The Contractor was reminded to provide a stopper for the
drain hole of the drip tray at S19 and S28.
¡± The Contractor was reminded to repair the kerb of the drip tray on the vessel Hai Bo 8.
¡± The Contractor was reminded to place the drip tray properly.
¡± The Contractor was reminded to
replace the broken drip tray at N13.
¡± The Contractor was reminded to
clean up the oil leakage and provide a drain plug for the drip tray at S25.
¡± The Contactor was reminded to put
the oil drum into drip tray at N1.
¡± The Contractor was reminded to remove the chemical container at N4.
¡± The Contractor was reminded to remove the stagnant water in the
H-beam at N4, N13, S7 and S23.
¡± The Contractor
was reminded to remove
the stagnant water inside the wheel washing facility at N4 and S22.
¡± The Contractor was reminded to clear the stagnant water at N1.
¡± The Contractor was reminded to remove the stagnant
water near the backfill material at S11 and S15 storage area.
¡± The Contractor was reminded to
remove the stagnant water from the drip tray at S11.
¡± The Contractor was reminded to cover the cement
bags at N20 and S15.
¡± The Contractor was reminded to provide a proper cover for
the cement mixing plant at N20.
¡± The Contractor was reminded to enclose the gap between silt curtain and sea
shore at Portion X and S7.
¡± The Contractor was reminded to provide a proper cover for the rubbish bin at
S11.
¡±
The Contractor was reminded to to clean the walkway of vessels Hai Bo 8 and Harbor
Sky 68; dusty
material and surround the gullies with sand bags at N20; dusty
materials from the barge edge at vessel Hai Bo 8 and Chang Sheng 306.
¡± The Contractor was reminded to provide impervious sheet to cover the gap between
vessel Hai Bo 8 and Chang Sheng 306 during dusty materials transfer at
S7.
¡± The Contractor was reminded to
provide sand bags along the deck edge and remove the broken sand bags at the
deck edge to prevent washing away of sand into the sea.
¡± The Contractor was reminded to remove the rubbish from vessel Sun Tat 82 and
N13 and skip at S19 and N1.
¡± The Contractor was reminded to repair the mechanical cover of
dump truck (licence plate: CF 1078) at S15-S16 and dump truck (licence plate: CN920) at S15.
¡± The Contractor was reminded to provide an enhanced
water sprinkler system for the drilling
works at N4 and S15.
¡± The
Contractor was reminded to spray water on the stockpiles of dusty materials at
N13, during dust material loading of dump truck at S15 and during excavation at
S11.
¡± The Contractor was reminded to
spray water regularly on the dry fill materials.
¡± The
Contractor was reminded to provide instruction sign for the wheel washing
facility at N13.
¡± The
Contractor was reminded to provide high pressure water jet for N20 wheel
washing facility.
¡± The Contractor was reminded to provide sleeve tubing for the piling works at
S11.
¡± The Contractor was reminded to remove the construction equipment near the
retained trees at S11-S15.
¡± The Contractor was reminded to fill up the recesses
of concrete blocks at S7, S11, S19 and S25.
¡± The Contractor was reminded to
repair the excavator to prevent oil leakage at Shun Tat 82.
¡± The Contractor was reminded to
repair the noise barriers at S25.
¡± The Contractor was reminded to clean
up the oil stain on the road surface at S16.
¡± The Contractor was reminded to
check and ensure the functioning of wastewater treatment system and provide
proper treatment for all wastewater generated on-site before discharge.
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 ninth Quarterly EM&A
Report which summarises the
monitoring results and audit findings of the EM&A programme during the
reporting period from 1 September 2014 to 30 November 2014.
Air Quality
5.3.2
For AMS5, no Action and Limit Level exceedances of 1-hr TSP and 24-hr
TSP were recorded at AMS 5
during the reporting period.
5.3.3
For AMS6, no Action and Limit Level exceedances
of 1-hr TSP level and no Limit Level exceedances of 24-hr TSP were recorded
during the reporting period. An Action Level exceedance of 24-hr TSP level was
recorded on 15 and 27 October 2014, respectively.
Noise
5.3.4
For construction noise, there
were no Action Level and Limit Level exceedances during the reporting
period.
Water Quality
5.3.5
During the reporting period, nine Action Level
exceedances and three Limit Level exceedances of suspended solid level were
recorded. No Action and Limit Level exceedances of dissolved oxygen level were
recorded. No Action
and Limit Level exceedances of turbidity
were recorded.
Dolphin
5.3.6
There were two Action Level exceedances of dolphin monitoring for the quarterly monitoring
data (September ¡V November 2014).
5.3.7
During this quarter of dolphin
monitoring, no adverse impact from the activities of this construction project
on Chinese White Dolphins was noticeable from general observations.
5.3.8
Although dolphins rarely
occurred in the area of HKLR03 construction in the past and during the baseline
monitoring period, it is apparent that dolphin usage has been significantly
reduced in NEL in 2012 - 2014, and many individuals have shifted away from the
important habitat around the Brothers Islands.
5.3.9
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
5.3.10 This measurement result was
generally and relatively higher than the baseline measurement at S1, S2, S3 and
S4. The mudflat level is continuously increased.
5.3.11 Impact
water quality monitoring in San Tau (monitoring station SR3) was conducted in September
2014. The monitoring parameters included
dissolved oxygen (DO), turbidity and suspended solids (SS).
Mudflat - Ecology
5.3.12
The September 2014 survey was the eighth 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
5.3.13
Environmental site inspection
was carried out on 3, 10, 17 and 26 September 2014, 3, 8, 15, 22 and 31 October 2014 and 5, 12, 19 and
28 November 2014. Recommendations on remedial actions
were given to the Contractors for the deficiencies identified during the site
inspections.
5.3.14
There were no environmental
complaints received during this reporting period.
5.3.15
No notification of summons and
prosecution was received during the reporting period.