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. 22 (December 2017 to February 2018)
21 June 2018
Revision 1
Contents
Executive Summary
1.4 Construction
Works Undertaken During the Reporting Period
2.1 Summary
of EM&A Requirements
3....... Environmental Monitoring
and Audit
3.1 Implementation of Environmental Measures
3.2 Air Quality Monitoring Results
3.4 Water Quality
Monitoring Results
3.5 Dolphin Monitoring Results
3.6 Mudflat Monitoring Results
3.7 Solid and Liquid Waste Management Status
3.8 Environmental Licenses and Permits
4....... Environmental Complaint and Non-compliance
4.2 Summary of Environmental Complaint,
Notification of Summons and Successful Prosecution
5....... Comments, Recommendations
and Conclusion
Figures
Figure 1.1 Location
of the Site
Figure 2.1 Environmental
Monitoring Stations
Figure 2.2 Transect
Line Layout in Northwest and Northeast Lantau Survey Areas
Appendices
Appendix
A Environmental
Management Structure
Appendix B Construction
Programme
Appendix
C Location
of Works Areas
Appendix
D Event
and Action Plan
Appendix E Implementation
Schedule of Environmental Mitigation Measures
Appendix
F Site
Audit Findings and Corrective Actions
Appendix
G Air Quality Monitoring Data and
Graphical Plots
Appendix H Noise Monitoring Data and Graphical
Plots
Appendix I Water
Quality Monitoring Data and Graphical Plots
Appendix J Dolphin
Monitoring Results
Appendix
L Summary
of Environmental Licenses and Permits
Appendix N Cumulative
Statistics on Complaints
Appendix O Mudflat
Monitoring Results
Executive Summary
The Hong Kong-Zhuhai-Macao Bridge (HZMB) Hong Kong Link Road (HKLR)
serves to connect the HZMB Main Bridge at the Hong Kong Special Administrative
Region (HKSAR) Boundary and the HZMB Hong Kong Boundary Crossing Facilities
(HKBCF) located at the north eastern waters of the Hong Kong International
Airport (HKIA).
The HKLR project has been separated into two contracts. They are Contract No. HY/2011/03 Hong
Kong-Zhuhai-Macao Bridge Hong Kong Link Road-Section between Scenic Hill and
Hong Kong Boundary Crossing Facilities (hereafter referred to as the Contract)
and Contract No. HY/2011/09 Hong Kong-Zhuhai-Macao Bridge Hong Kong Link
Road-Section between HKSAR Boundary and Scenic Hill.
China State Construction Engineering (Hong Kong) Ltd. was awarded by
Highways Department as the Contractor to undertake the construction works of
Contract No. HY/2011/03. The main works of the Contract include land tunnel at
Scenic Hill, tunnel underneath Airport Road and Airport Express Line,
reclamation and tunnel to the east coast of the Airport Island, at-grade road
connecting to the HKBCF and highway works of the HKBCF within the Airport
Island and in the vicinity of the HKLR reclamation. The Contract is part of the HKLR Project
and HKBCF Project, these projects are considered to be ¡§Designated Projects¡¨,
under Schedule 2 of the Environmental Impact Assessment (EIA) Ordinance (Cap
499) and EIA Reports (Register No. AEIAR-144/2009 and AEIAR-145/2009) were
prepared for the Project. The
current Environmental Permit (EP) EP-352/2009/D for HKLR and EP-353/2009/K for
HKBCF were issued on 22 December 2014 and 11 April 2016, respectively. These
documents are available through the EIA Ordinance Register. The construction
phase of Contract was
commenced on 17 October 2012.
BMT Asia Pacific Limited has been appointed by the Contractor to
implement the Environmental Monitoring & Audit (EM&A) programme for the
Contract in accordance with the Updated EM&A Manual for HKLR (Version 1.0)
and will be providing environmental team services to the Contract.
This is the twenty-second Quarterly EM&A report for the Contract
which summarizes the monitoring results and audit findings of the EM&A
programme during the reporting period from 1 November 2017 to 28 February 2018.
Environmental
Monitoring and Audit Progress
The EM&A programme were undertaken in
accordance with the Updated EM&A Manual for HKLR (Version 1.0). A summary of the monitoring activities
during this reporting period is presented as below:
Monitoring Activity |
Monitoring
Date |
|||
December 2017 |
January
2018 |
February 2018 |
||
Air
Quality |
1-hr TSP |
4, 8, 14, 20, 22, 28 and 29 |
4, 10, 16, 22 and 26 |
1, 7, 13, 14, 20 and 26 |
24-hr TSP |
1, 7, 13, 19, 23 and 29 for AMS5 1, 7, 13, 19 and 23 for AMS6 |
3, 9, 15, 19, 25 and 31 for AMS5 4, 9, 15, 19, 25 and 31 for AMS6 |
6, 12, 15, 20 and 23 |
|
Noise |
4, 14, 20 and 28 |
4, 10, 16 and 22 |
6, 16, 22 and 28 |
|
Water Quality |
1, 4, 6, 8, 11, 13, 15, 18, 20, 22, 25, 27
and 29 |
1, 3, 5, 8, 10, 12, 15, 17, 19, 22, 24, 26,
29 and 31 |
2, 5, 7, 9, 12, 14, 17, 19, 21, 23, 26 and
28 |
|
Chinese
White Dolphin |
5, 12, 15 and 20 |
2, 8, 16 and 25 |
2, 9, 14 and 22 |
|
Mudflat Monitoring (Ecology) |
9, 10, 16, 17, 21 and 22 |
-- |
-- |
|
Mudflat Monitoring (Sedimentation rate) |
7 |
-- |
-- |
|
Site Inspection |
6, 4, 20 and 30 |
3 ,10, 17 and 26 |
1,7, 14 and 23 |
Due to boat unavailability, the dolphin
monitoring was rescheduled from 22 December 2017 to 20 December 2017, and from
22 January 2018 to 25 January 2018.
The monitoring time for 24-hr TSP
monitoring on 29 December 2017 at AMS6 (Dragonair Building) was discovered less
than 24 hours due to power interruption. The 24-hr TSP monitoring result
obtained at AMS6 on 29 December 2017 was considered invalid. Due to power
failure and malfunction of HVS from 29 December 2017 to 3 January 2018, 24-hr
TSP monitoring could not be conducted at such period. Competent people were
arranged to check the power supply and repair HVS on 3 and 4 January 2018
respectively. 24-hr TSP monitoring at AMS6 has been resumed on 4 January 2018.
Due to suitable weather condition, the
mudflat monitoring was rescheduled from 23 December 2017 to 21 December 2017.
Due to power failure and malfunction of
HVS at AMS6 from 29 December 2017 to 3 January 2018, 24-hr TSP monitoring could
not be conducted at such period. Competent people were arranged to check the
power supply and repair HVS on 3 and 4 January 2018 respectively. 24-hr TSP
monitoring at AMS6 was resumed on 4 January 2018.
Water quality monitoring was not
conducted at station CS2(A) during mid ebb and mid flood tide on 8 January 2018
due to rough sea condition and safety concern. Substitute monitoring was not
conducted on 9 January 2018 at station CS2(A) due to rough sea condition and
safety concern.
Fishing activity was observed near station SR4(N)
on 2 February 2018. Due to blockage of access to the station SR4(N) by a
fishing net, the water quality monitoring at station SR4(N) was temporarily
conducted at coordinate: 814620E, 818016N during mid ebb tide on 2 February
2018.
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 |
5 |
0 |
24-hr TSP |
2 |
0 |
|
Noise |
Leq
(30 min) |
0 |
0 |
Water
Quality |
Suspended
solids level (SS) |
11 |
1 |
Turbidity
level |
0 |
0 |
|
Dissolved
oxygen level (DO) |
0 |
0 |
|
Dolphin
Monitoring |
Quarterly
Analysis (Dec 2017 to Feb 2018) |
2 |
0 |
All investigation reports for exceedances of the Contract have been
submitted to ENPO/IEC for comments and/or follow up to identify whether the
exceedances occurred related to other HZMB contracts.
Implementation of Mitigation Measures
Site inspections were carried out on a weekly basis to monitor the
implementation of proper environmental pollution control and mitigation
measures for the Project. Potential
environmental impacts due to the construction activities were monitored and
reviewed.
Complaint Log
There were two complaints received in relation to the environmental
impacts during the reporting period.
A summary of environmental complaints for this reporting period is as
follows:
Environmental Complaint No. |
Date of Complaint Received |
Description of Environmental Complaint |
COM-2017-129 |
ENPO¡¦s email to the
Supervising Officer¡¦s Representative and Contractor on 8 January 2018 that
HyD received a complaint lodged by a member of the public regarding
cleanliness problem at East Coast Road on 29 December 2017 |
Cleanliness problem
at East Coast Road |
COM-2018-132 |
HyD (SOR referred the email from HyD to Contractor and ET on 13
February 2018) and EPD (ENPO referred the email from EPD to SOR, SOR sent the
email to Contractor and ET on 14 February 2018) |
Complaint
about Dust, Water Quality, Construction Waste, Noise and Vibration for the
Contract |
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 subsequent 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: 813273E,
818850N) was observed inside the perimeter silt curtain of Contract HY/2010/02
on 1 July 2013, as such the original impact water quality monitoring location
at IS(Mf)9 was temporarily shifted outside the silt curtain. As advised by the
Contractor of HY/2010/02 in August 2013, the perimeter silt curtain was shifted
to facilitate safe anchorage zone of construction barges/vessels until end of
2013 subject to construction progress.
Therefore, water quality monitoring station IS(Mf)9 was shifted to
813226E and 818708N since 1 July 2013.
According to the water quality monitoring team¡¦s observation on 24 March
2014, the original monitoring location of IS(Mf)9 was no longer enclosed by the
perimeter silt curtain of Contract HY/2010/02. Thus, the impact water quality
monitoring works at the original monitoring location of IS(Mf)9 has been
resumed since 24 March 2014.
Transect lines 1, 2, 7, 8, 9 and 11 for dolphin monitoring have been
revised due to the obstruction of the permanent structures associated with the
construction works of HKLR and the southern viaduct of TM-CLKL, as well as
provision of adequate buffer distance from the Airport Restricted Areas. The EPD issued a memo and confirmed that
they had no objection on the revised transect lines on 19 August 2015.
The water quality monitoring stations at IS10 (Coordinate: 812577E,
820670N) and SR5 (811489E, 820455N) are located inside Hong Kong International
Airport (HKIA) Approach Restricted Areas. The previously granted Vessel's Entry
Permit for accessing stations IS10 and SR5 were expired on 31 December 2016.
During the permit renewing process, the water quality monitoring location was
shifted to IS10(N) (Coordinate: 813060E, 820540N) and SR5(N) (Coordinate:
811430E, 820978N) on 2, 4 and 6 January 2017 temporarily. The permit has been
granted by Marine Department on 6 January 2017. Thus, the impact water quality
monitoring works at original monitoring location of IS10 and SR5 has been
resumed since 9 January 2017.
Transect lines 2, 3, 4, 5, 6 and 7 for dolphin monitoring have been
revised and transect line 24 has been added due to the presence of a work zone
to the north of the airport platform with intense construction activities in
association with the construction of the third runway expansion for the Hong
Kong International Airport. The EPD issued a memo and confirmed that they had
no objection on the revised transect lines on 28 July 2017. The alternative
dolphin transect lines are adopted starting from August¡¦s dolphin monitoring.
A new water quality monitoring team has been employed for carrying out
water quality monitoring work for the Contract starting from 23 August 2017.
Due to marine work of the Expansion of Hong Kong International Airport into a
Three-Runway System (3RS Project), original locations of water quality
monitoring stations CS2, SR5 and IS10 are enclosed by works boundary of 3RS
Project. Alternative impact water quality monitoring stations, naming as
CS2(A), SR5(N) and IS10(N) was approved on 28 July 2017 and were adopted
starting from 23 August 2017 to replace the original locations of water quality
monitoring for the Contract.
The role and responsibilities as the ET Leader of the Contract was
temporarily taken up by Mr Willie Wong instead of Ms Claudine Lee from 25
September 2017 to 31 December 2017.
The topographical condition of the water monitoring stations SR3
(Coordinate: 810525E, 816456N), SR4 (Coordinate: 814760E, 817867N), SR10A
(Coordinate: 823741E, 823495N) and SR10B (Coordinate: 823686E, 823213N) cannot
be accessed safely for undertaking water quality monitoring. The water quality
monitoring has been temporarily conducted at alternative stations, namely
SR3(N) (Coordinate 810689E, 816591N), SR4(N) (Coordinate: 814705E, 817859N) and
SR10A(N) (Coordinate: 823644E, 823484N) since 1 September 2017. The water
quality monitoring at station SR10B was temporarily conducted at Coordinate:
823683E, 823187N on 1, 4, 6, 8 September 2017 and has been temporarily
fine-tuned to alternative station SR10B(N2) (Coordinate: 823689E, 823159N)
since 11 September 2017. Proposal for permanently relocating the aforementioned
stations was approved by EPD on 8 January 2018.
Table 1.1 Construction
Activities during Reporting Period
Description of Activities |
Site Area |
Stockpiling |
WA7 |
Dismantling/trimming of temporary 40mm stone platform for construction
of seawall |
Portion X |
Construction of seawall |
Portion X |
Loading and unloading of filling materials |
Portion X |
Backfilling at Scenic Hill Tunnel (Cut & Cover Tunnel) |
Portion X |
Excavation for HKBCF to Airport Tunnel &
construction of tunnel box structure |
Portion X |
Works for diversion |
Airport Road |
Utilities detection |
Airport Road/ Airport Express Line/ East Coast Road |
Establishment of site access |
Airport Road/ Airport Express Line/ East Coast Road |
Mined tunnel lining / box jacking transition zone
rebar fixing underneath Airport Road and Airport Express Line |
Airport Road and Airport Express Line |
Excavation and lateral support works & Construction of Tunnel Box
Structure for HKBCF to Airport Tunnel West (Cut & Cover Tunnel) |
Airport Road |
Excavation and lateral support works & construction of tunnel box
structure for HKBCF to Airport Tunnel East (Cut & Cover Tunnel) |
Portion X |
E&M/ Backfilling/ Bitumen works for HKBCF to Airport Tunnel West
(Cut & Cover Tunnel) |
Airport Road |
E&M/ Backfilling/ Bitumen works for HKBCF to Airport Tunnel East
(Cut & Cover Tunnel) |
Portion X |
Superstructure and finishing works for Highway Operation and
Maintenance Area Building |
Portion X |
Finishing works for Highway Operation and Maintenance Area Building |
Portion X |
Finishing works for Scenic Hill Tunnel West Portal Ventilation
Building |
West Portal |
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), |
NMS 5 |
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: ¡P Control/Far Field
Stations: ¡P Sensitive Receiver
Stations: |
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 |
-- |
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) |
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 |
(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.
Table
2.4 Action
and Limit Level for Dolphin Impact Monitoring
|
North
Lantau Social Cluster |
|
NEL |
NWL |
|
Action Level |
STG < 70% of baseline
& |
STG < 70% of baseline
& |
Limit Level |
STG < 40% of baseline
& |
Remarks:
(1)
STG
means quarterly average encounter rate of number of dolphin sightings.
(2)
ANI
means quarterly average encounter rate of total number of dolphins.
(3)
For
North Lantau Social Cluster, AL will be triggered if either NEL or NWL fall
below the criteria; LL will be triggered if both NEL and NWL fall below the
criteria.
Table
2.5 Derived
Value of Action Level (AL) and Limit Level (LL)
|
North
Lantau Social Cluster |
|
NEL |
NWL |
|
Action Level |
STG < 4.2 & ANI
< 15.5 |
STG < 6.9 & ANI
< 31.3 |
Limit Level |
(STG < 2.4 & ANI
< 8.9) and (STG < 3.9 & ANI < 17.9) |
Remarks:
(1)
STG
means quarterly average encounter rate of number of dolphin sightings.
(2)
ANI
means quarterly average encounter rate of total number of dolphins.
(3)
For
North Lantau Social Cluster, AL will be triggered if either NEL or NWL fall
below the criteria; LL will be triggered if both NEL and NWL fall below the
criteria.
Table 3.1 Summary
of 1-hour TSP Monitoring Results Obtained During the Reporting Period
Reporting Period |
Monitoring Station |
Average (mg/m3) |
Range (mg/m3) |
Action Level (mg/m3) |
Limit Level (mg/m3) |
December 2017 |
AMS5 |
41 |
13 ¡V 95 |
352 |
500 |
AMS6 |
56 |
17 ¡V 100 |
360 |
||
January 2018 |
AMS5 |
108 |
16 ¡V 398 |
352 |
|
AMS6 |
117 |
15 ¡V 412 |
360 |
||
February 2018 |
AMS5 |
49 |
23 ¡V 79 |
352 |
|
AMS6 |
45 |
17 ¡V 76 |
360 |
Table 3.2 Summary of 24-hour TSP Monitoring Results Obtained During the Reporting Period
Reporting Period |
Monitoring Station |
Average (mg/m3) |
Range (mg/m3) |
Action Level (mg/m3) |
Limit Level (mg/m3) |
December
2017 |
AMS5 |
88 |
43 ¡V 139 |
164 |
260 |
AMS6 |
172 |
89 ¡V 253 |
173 |
||
January
2018 |
AMS5 |
54 |
44 ¡V 67 |
164 |
|
AMS6 |
77 |
62 ¡V 100 |
173 |
||
February
2018 |
AMS5 |
66 |
36 ¡V 85 |
164 |
|
AMS6 |
94 |
44 ¡V 138 |
173 |
Table 3.3 Summary of Construction Noise Monitoring Results Obtained
During the Reporting Period
Reporting period |
Monitoring
Station |
Average Leq
(30 mins), dB(A)* |
Range of Leq
(30 mins), dB(A)* |
Action Level |
Limit Level Leq
(30 mins), dB(A) |
December
2017 |
NMS5 |
58 |
57 ¡V 59 |
When one documented complaint is received |
75 |
January
2018 |
58 |
57 ¡V 60 |
|||
February
2018 |
58 |
56 ¡V 59 |
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
Summary of Survey Effort
and Dolphin Sightings
Table 3.4 Dolphin
Encounter Rates (Sightings Per 100 km of Survey Effort) During Reporting Period
(December
2017 ¡V February 2018)
Survey Area |
Dolphin Monitoring |
Encounter rate (STG) |
Encounter rate (ANI) |
Primary Lines Only |
Primary Lines Only |
||
Northeast Lantau |
Set 1 (5 & 12 Dec 2017) |
0.00 |
0.00 |
Set 2 (15 & 20 Dec 2017) |
0.00 |
0.00 |
|
Set 3 (2 & 8 Jan 2018) |
0.00 |
0.00 |
|
Set 4 (16 & 25 Jan 2018) |
0.00 |
0.00 |
|
Set 5 (2 & 9 Feb 2018) |
0.00 |
0.00 |
|
Set 6 (14 & 22 Feb 2018) |
0.00 |
0.00 |
|
Northwest Lantau |
Set 1 (5 & 12 Dec 2017) |
1.66 |
8.32 |
Set 2 (15 & 20 Dec 2017) |
8.39 |
22.37 |
|
Set 3 (2 & 8 Jan 2018) |
5.68 |
45.42 |
|
Set 4 (16 & 25 Jan 2018) |
3.43 |
3.43 |
|
Set 5 (2 & 9 Feb 2018) |
4.38 |
6.56 |
|
Set 6 (14 & 22 Feb 2018) |
4.97 |
8.29 |
Survey Area |
Encounter rate (STG) |
Encounter rate (ANI) |
||
Reporting Period |
Baseline Monitoring Period |
Reporting Period |
Baseline Monitoring Period |
|
Northeast Lantau |
0.0 |
6.00 ¡Ó 5.05 |
0.0 |
22.19 ¡Ó 26.81 |
Northwest Lantau |
4.75 ¡Ó 2.26 |
9.85 ¡Ó 5.85 |
15.73 ¡Ó 15.94 |
44.66 ¡Ó 29.85 |
Notes:
1) The encounter rates deduced from the baseline monitoring period have been
recalculated based only on the survey effort and on-effort sighting data made
along the primary transect lines under favourable conditions.
2) ¡Ó
denotes the standard deviation of the average encounter rates.
Table 3.6 Comparison of Average Dolphin Encounter Rates in
Northeast Lantau Survey Area from All Quarters of Impact Monitoring Period and
Baseline Monitoring Period (Sep ¡V Nov 2011)
Monitoring Period |
Encounter rate (STG) |
Encounter rate (ANI) |
September-November 2011 (Baseline) |
6.00 ¡Ó 5.05 |
22.19 ¡Ó 26.81 |
December 2012-February 2013 (Impact) |
3.14 ¡Ó 3.21* |
6.33 ¡Ó 8.64* |
March-May 2013 (Impact) |
0.42 ¡Ó 1.03 |
0.42 ¡Ó 1.03 |
June-August 2013 (Impact) |
0.88 ¡Ó 1.36 |
3.91 ¡Ó 8.36 |
September-November
2013
(Impact) |
1.01 ¡Ó 1.59 |
3.77 ¡Ó 6.49 |
December 2013-February 2014 (Impact) |
0.45 ¡Ó 1.10* |
1.34 ¡Ó 3.29* |
March-May 2014 (Impact) |
0.00 |
0.00 |
June-August 2014 (Impact) |
0.42 ¡Ó 1.04 |
1.69 ¡Ó 4.15 |
September-November 2014 (Impact) |
0.00 |
0.00 |
December 2014-February 2015 (Impact) |
0.00* |
0.00* |
March-May 2015 (Impact) |
0.00 |
0.00 |
June-August 2015 (Impact) |
0.44 ¡Ó 1.08 |
0.44 ¡Ó 1.08 |
September-November 2015 (Impact) |
0.00 |
0.00 |
December 2015-February 2016 (Impact) |
0.00* |
0.00* |
March-May 2016 (Impact) |
0.00 |
0.00 |
June-August 2016 (Impact) |
0.00 |
0.00 |
September-November 2016 (Impact) |
0.00 |
0.00 |
December 2016-February 2017 (Impact) |
0.00* |
0.00* |
March-May 2017 (Impact) |
0.00 |
0.00 |
June-August 2017 (Impact) |
0.00 |
0.00 |
September-November 2017 (Impact) |
0.00 |
0.00 |
December 2017-February 2018 (Impact) |
0.00* |
0.00* |
Notes:
1) The encounter rates deduced from the baseline
monitoring period have been recalculated based only on survey effort and
on-effort sighting data made along the primary transect lines under favourable
conditions.
2) ¡Ó denotes the standard deviation of the average
encounter rates.
3) The encounter rates in winter months were in blue
and marked with asterisk.
Table 3.7 Comparison
of Average Dolphin Encounter Rates in Northwest Lantau Survey Area from All
Quarters of Impact Monitoring Period and Baseline Monitoring Period (Sep ¡V Nov
2011)
Monitoring Period |
Encounter rate
(STG)
(no. of on-effort
dolphin sightings per 100 km of survey effort) |
Encounter rate
(ANI)
(no. of dolphins from all on-effort sightings per 100 km of survey
effort) |
September-November
2011 (Baseline) |
9.85 ¡Ó 5.85 |
44.66 ¡Ó 29.85 |
December 2012-February 2013 (Impact) |
8.36 ¡Ó 5.03* |
35.90 ¡Ó 23.10* |
March-May 2013 (Impact) |
7.75 ¡Ó 3.96 |
24.23 ¡Ó 18.05 |
June-August 2013 (Impact) |
6.56 ¡Ó 3.68 |
27.00 ¡Ó 18.71 |
September-November 2013 (Impact) |
8.04 ¡Ó 1.10 |
32.48 ¡Ó 26.51 |
December 2013-February 2014 (Impact) |
8.21 ¡Ó 2.21* |
32.58 ¡Ó 11.21* |
March-May 2014 (Impact) |
6.51 ¡Ó 3.34 |
19.14 ¡Ó 7.19 |
June-August 2014 (Impact) |
4.74 ¡Ó 3.84 |
17.52 ¡Ó 15.12 |
September-November 2014 (Impact) |
5.10 ¡Ó 4.40 |
20.52 ¡Ó 15.10 |
December 2014-February 2015 (Impact) |
2.91 ¡Ó 2.69* |
11.27 ¡Ó 15.19* |
March-May 2015 (Impact) |
0.47 ¡Ó 0.73 |
2.36 ¡Ó 4.07 |
June-August 2015 (Impact) |
2.53 ¡Ó 3.20 |
9.21 ¡Ó 11.57 |
September-November 2015 (Impact) |
3.94 ¡Ó 1.57 |
21.05 ¡Ó 17.19 |
December 2015-February 2016 (Impact) |
2.64 ¡Ó 1.52* |
10.98 ¡Ó 3.81* |
March-May 2016 (Impact) |
0.98 ¡Ó 1.10 |
4.78 ¡Ó 6.85 |
June-August 2016 (Impact) |
1.72 ¡Ó 2.17 |
7.48 ¡Ó 10.98 |
September-November 2016 (Impact) |
2.86 ¡Ó 1.98 |
10.89 ¡Ó 10.98 |
December 2016-February 2017 (Impact) |
3.80 ¡Ó 3.79* |
14.52 ¡Ó 17.21* |
March-May 2017 (Impact) |
0.93 ¡Ó 1.03 |
5.25 ¡Ó 9.53 |
June-August 2017 (Impact) |
2.20 ¡Ó 2.88 |
6.58 ¡Ó 8.12 |
September-November 2017 (Impact) |
3.12 ¡Ó 1.91 |
10.35 ¡Ó 9.66 |
December 2017-February 2018 (Impact) |
4.75 ¡Ó 2.26* |
15.73 ¡Ó 15.94* |
Notes:
1) The encounter rates deduced from the baseline monitoring period have
been recalculated based only on survey effort and on-effort sighting data made along
the primary transect lines under favourable conditions.
2) ¡Ó denotes
the standard deviation of the average encounter rates.
3) The encounter rates in winter months were in
blue and marked with asterisk.
Table 3.8 Comparison
of Average Dolphin Group Sizes between Reporting Period (Dec 2017¡V Feb 2018)
and Baseline Monitoring Period (Sep ¡V Nov 2011)
Survey Area |
Average Dolphin Group Size |
|
Reporting Period |
Baseline Monitoring Period |
|
Overall |
2.65 ¡Ó 2.50 (n = 17) |
3.72 ¡Ó 3.13 (n = 66) |
Northeast Lantau |
--- |
|
Northwest Lantau |
2.65 ¡Ó 2.50 (n = 17) |
3.92 ¡Ó 3.40 (n = 49) |
Note:
1) ¡Ó denotes the standard deviation of the average
group size.
Table 3.9 Measured
Mudflat Surface Level Results
Baseline Monitoring |
Impact Monitoring |
|||||
Monitoring Station |
Easting |
Northing (m) |
Surface Level |
Easting |
Northing (m) |
Surface Level (mPD) |
S1 |
810291.160 |
816678.727 |
0.950 |
810291.162 |
816678.744 |
1.117 |
S2 |
810958.272 |
815831.531 |
0.864 |
810958.253 |
815831.503 |
0.986 |
S3 |
810716.585 |
815953.308 |
1.341 |
810716.564 |
815953.329 |
1.479 |
S4 |
811221.433 |
816151.381 |
0.931 |
811221.435 |
816151.339 |
1.099 |
Table 3.10 Comparison
of Measurement
Comparison of measurement |
Remarks and Recommendation |
|||
Monitoring Station |
Easting |
Northing (m) |
Surface Level |
|
S1 |
0.002 |
0.017 |
0.167 |
Level continuously
increased |
S2 |
-0.019 |
-0.028 |
0.122 |
Level continuously increased |
S3 |
-0.021 |
0.021 |
0.138 |
Level continuously increased |
S4 |
0.002 |
-0.042 |
0.168 |
Level continuously increased |
Table 3.11 Impact Water Quality Monitoring Results (Depth Average)
Date |
Mid Ebb Tide |
Mid Flood Tide |
||||
DO (mg/L) |
Turbidity
(NTU) |
SS (mg/L) |
DO (mg/L) |
Turbidity
(NTU) |
SS (mg/L) |
|
1-Dec-17 |
7.1 |
6.2 |
6.0 |
7.1 |
6.2 |
6.0 |
4-Dec-17 |
7.1 |
6.2 |
7.6 |
7.0 |
7.9 |
13.7 |
6-Dec-17 |
7.2 |
10.4 |
11.2 |
7.2 |
9.8 |
10.9 |
8-Dec-17 |
7.2 |
8.6 |
13.4 |
7.0 |
10.8 |
12.3 |
11-Dec-17 |
7.6 |
6.5 |
13.0 |
7.4 |
8.2 |
13.2 |
13-Dec-17 |
7.3 |
4.3 |
6.5 |
7.4 |
6.5 |
11.8 |
15-Dec-17 |
7.1 |
6.1 |
6.8 |
7.4 |
5.3 |
6.5 |
18-Dec-17 |
7.4 |
5.0 |
6.9 |
7.3 |
5.9 |
5.6 |
20-Dec-17 |
7.9 |
6.6 |
8.3 |
7.6 |
8.3 |
13.1 |
22-Dec-17 |
8.0 |
6.2 |
8.8 |
7.9 |
6.0 |
9.6 |
25-Dec-17 |
8.1 |
7.6 |
7.9 |
8.1 |
6.6 |
8.5 |
27-Dec-17 |
7.9 |
4.2 |
3.8 |
7.8 |
6.6 |
7.4 |
29-Dec-17 |
7.9 |
5.5 |
5.6 |
7.9 |
5.5 |
5.1 |
Average |
7.5 |
6.4 |
8.1 |
7.5 |
7.2 |
9.5 |
|
Mudflat
Ecology Monitoring
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.
3.6.16
In the present survey, two species of horseshoe crab Carcinoscorpius
rotundicauda (total 8 ind.) and Tachypleus
tridentatus (total 3 ind.) were recorded. The recorded individuals were scattered
along the shoreline from TC3 to ST on similar substratum (fine sand or soft mud, slightly submerged). No grouping was observed. Photo records were shown in
Figure 3.1 of Appendix O
while the complete survey records were listed in Annex II of Appendix O.
3.6.17
Table 3.1 of Appendix O summarizes the survey results of horseshoe crab in the
present survey. For Carcinoscorpius rotundicauda, very few individuals were found in TC3 (1 ind.) and ST (5 ind.) only
resulting in very low search record (0.2-0.8 ind. hr-1 person-1). The average body size was 44.24 mm (prosomal width ranged 27.64-79.79 mm) in ST.
3.6.18
For Tachypleus
tridentatus, very few individuals were
found in TC3 (2 ind.) and ST (3 ind.) either resulting in very low search
record (0.3-0.5 ind. hr-1 person-1). The average body
sizes were 43.92 mm (prosomal width ranged 37.23-50.61 mm) in TC3 and 58.67 mm (37.34-73.45 mm) in ST.
3.6.19
In the previous survey of Mar. 2015, there
was one important finding that a mating pair of Carcinoscorpius rotundicauda was found in ST (prosomal width: male
155.1 mm, female 138.2 mm) (Figure 3.2
of Appendix O). It indicated the importance of ST as a breeding ground of
horseshoe crab. In Jun. 2017, mating pairs
of Carcinoscorpius rotundicauda were
also found in TC2 (male 175.27 mm, female 143.51 mm) and TC3 (male 182.08 mm,
female 145.63 mm) (Figure 3.2 of Appendix O). In Dec. 2017 (present survey), one mating pair was
of Carcinoscorpius rotundicauda was
found in TC3 (male 127.80 mm, female 144.61 mm) (Figure
3.2 of Appendix O). These mating pairs
indicated that breeding of horseshoe crab could be possible along the coast of
Tung Chung Wan rather than ST only, as long as suitable substratum was
available. The recorded mating pairs were found nearly burrowing in soft mud at
low tidal level (0.5-1.0 m above C.D.). The smaller male was holding the
opisthosoma (abdomen carapace) of larger female from behind. Moreover, suitable
breeding period was believed in wet season (Mar - Sep.) because tiny
individuals (i.e. newly hatched) were usually recorded in Jun. and Sep. every
year.
3.6.20
In the previous surveys (Jun. 2016, Jun.
2017, Sep. 2017) present survey (Dec. 2017), there were occasional records of large
individuals of Carcinoscorpius
rotundicauda (prosomal width ranged 114.45- 178.67 mm, either single or in pair) in ST (Figure 3.3 of Appendix O). Based on
their sizes, it indicated that individuals of prosomal width larger than 100 mm
would progress its nursery stage from intertidal habitat to sub-tidal habitat
of Tung Chung Wan. These large individuals might move onto intertidal shore
occasionally during high tide for foraging and breeding. Because they should be
inhabiting sub-tidal habitat most of the time. Their records were excluded from
the data analysis to avoid mixing up with juvenile population living on
intertidal habitat.
3.6.21 No marked individual of horseshoe crab was
recorded in the present survey. Some marked individuals were found in the
previous surveys of Sep. 2013, Mar. 2014 and Sep. 2014. All of them were
released through a conservation programme in charged 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 crab population might be
restored in the natural habitat. Through a personal conversation with Prof.
Shin, about 100 individuals were released in the sampling zone ST on 20 June
2013. All of them were marked with color tape and internal chip detected by
specific chip sensor. There should be second round of release between June and
September 2014 since new marked individuals were found in the survey of Sep.
2014.
3.6.22 The artificial bred individuals, if found,
would be excluded from the results of present monitoring programme in order to
reflect the changes of natural population. However, the mark on their prosoma
might have been detached during moulting after a certain period of release. The
artificially released individuals were no longer distinguishable from the
natural population without the specific chip sensor. The survey data collected
would possibly cover both natural population and artificially bred individuals.
Population
difference among the sampling zones
3.6.23
Figures
3.4 and 3.5 of Appendix O
show the changes of number of individuals, mean prosomal width and search
record of horseshoe crabs Carcinoscorpius
rotundicauda and Tachypleus
tridentatus respectively in every sampling zone throughout the monitoring
period.
3.6.24
For TC3 and ST, medium to high search records (i.e. number of
individuals) of both species were always found in wet season (Jun. and Sep.).
The search record of ST was higher from Sep. 2012 to Jun. 2014 while it was
replaced by TC3 from Sep. 2014 to Jun. 2015. The search records were similar
between two sampling zones from Sep. 2015 to Jun. 2016. In Sep. 2016, the
search record of Carcinoscorpius
rotundicauda in ST was much higher than TC3. From Mar. to Jun. 2017, the
search records of both species were similar again between two sampling zones.
It showed a natural variation of horseshoe crab population in these two zones
due to weather condition and tidal effect. No obvious difference of horseshoe
crab population was noted between TC3 and ST. In Sep. 2017, the search records
of both horseshoe crab species decreased except the Carcinoscorpius rotundicauda in TC3. The survey results were
different from previous findings that there were usually higher search records
in Sep. One possible reason was that the serial cyclone hit decreased horseshoe
crab activity (totally 4 cyclone records between Jun. and Sep. 2017, to be
discussed in 'Seagrass survey' section).
3.6.25
For TC1, the search record was at low to medium level throughout the
monitoring period. The change of Carcinoscorpius
rotundicauda was relatively more variable than that of Tachypleus tridentatus. Relatively, the search record was very low
in TC2 (2 ind. in Sep. 2013; 1 ind. in Mar., Jun., Sep. 2014, Mar. and Jun.
2015; 4 ind. in Sep. 2015; 6 ind. in Jun. 2016; 1 ind. in Sep. 2016, Mar., Jun.
and Sep. 2017).
3.6.26
About the body size, larger individuals of Carcinoscorpius rotundicauda were
usually found in ST and TC1 relative to those in TC3. For Tachypleus tridentatus, larger individuals were usually found in ST
followed by TC3 and TC1. Throughout the monitoring
period, it was obvious that TC3 and ST (western shore of Tung Chung Wan) was an
important nursery ground for horseshoe crab especially newly hatched
individuals due to larger area of suitable substratum (fine sand or soft mud)
and less human disturbance (far from urban district). Relatively, other
sampling zones were not a suitable nursery ground especially TC2. Possible
factors were less area of suitable substratum (especially TC1) and higher human
disturbance (TC1 and TC2: close to urban district and easily accessible). In
TC2, large daily salinity fluctuation was a possible factor either since it was
flushed by two rivers under tidal inundation. The individuals inhabiting TC1
and TC2 were confined in small foraging area due to limited area of suitable
substrata. Although a mating pair of Carcinoscorpius
rotundicauda was found in TC2, the hatching rate and survival rate of newly
hatched individuals were believed very low.
Seasonal variation of
horseshoe crab population
3.6.27 Throughout
the monitoring period, the search record of horseshoe crab declined obviously
during dry season especially December (Figures
3.3 and 3.4 of Appendix O). In Dec. 2012, 4 individuals of Carcinoscorpius rotundicauda and 12 individuals of Tachypleus
tridentatus were found only. In Dec.
2013, no individual of horseshoe crab was found. In Dec. 2014, 2 individuals of Carcinoscorpius
rotundicauda and 8 individuals of Tachypleus tridentatus were found only. In Dec. 2015, 2 individuals of Carcinoscorpius
rotundicauda, 6 individuals of Tachypleus tridentatus and one newly hatched, unidentified individual were found only. The horseshoe crabs were inactive
and burrowed in the sediments during cold weather (<15 ºC). Similar results of low
search record in dry season were reported in a previous territory-wide survey
of horseshoe crab. For example, the search records in Tung Chung Wan were 0.17 ind. hr-1
person-1 and 0.00 ind. hr-1 person-1 in wet season and dry
season respectively (details see Li, 2008). Relatively the serach records were much higher in Dec. 2016. There were totally 70
individuals of Carcinoscorpius rotundicauda and 24 individuals of Tachypleus
tridentatus in TC3 and ST. Because the survey was arranged in
early December while the weather was warm with sunlight (~22 ¢XC during dawn according to
Hong Kong Observatory database, Chek Lap Kok station on 5 Dec). In contrast, there was no search record in TC1 and TC2 because the
survey was conducted in mid December with colder and cloudy weather (~20 ¢XC during dawn on 19 Dec). The horseshoe crab activity would decrease gradually with the colder climate. In Dec.
2017 (present survey), the weather was cold (13-15 ºC
during dawn) that very few individuals of both specis could be found as mentioned
above.
3.6.28 From
Sep. 2012 to 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 ever been believed of very low density in ST
hence the encounter rate was very low. Since 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 about 3 years ago along the coastline of Tung Chun Wan.
However, these individuals were still small while their walking trails were
inconspicuous. Hence there was no search record in previous sampling months.
Since Mar. 2014, more individuals were recorded due to larger size and higher
activity (i.e. more conspicuous walking trail).
3.6.29
For
Tachypleus tridentatus, sharp increase of number of individuals was
recorded in ST during the wet season of 2013 (from Mar. to Sep.). 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 in the following wet
seasons. The number of individuals increased in Mar. and Jun. 2014 followed by
a rapid decline in Sep. 2014. Then the number of individuals fluctuated
slightly in TC3 and ST until Mar. 2017. Apart from natural mortality, migration
from nursery soft shore to subtidal habitat was another possible cause. Since
the mean prosomal width of Tachypleus tridentatus continued to grow and
reached about 50 mm since Mar. 2014. Then it varied slightly between 35-65 mm
from Sep. 2014 to Mar. 2017. Most of the individuals might have reached a
suitable size (e.g. prosomal width 50-60 mm) strong enough to forage in
sub-tidal habitat. In Jun. 2017, the number of individuals increased sharply again
in TC3 and ST. Although mating pair of Tachypleus tridentatus was not
found in previous surveys, there should be new round of spawning in the wet
season of 2016. The individuals might have grown to a more conspicuous size in
2017 accounting for higher search record.
3.6.30 Recently,
Carcinoscorpius rotundicauda was a
more common horseshoe crab species in Tung Chung Wan. It was recorded in the
four sampling zones while the majority of population located in TC3 and ST. Due
to potential breeding last year, Tachypleus
tridentatus became common again and distributed in TC3 and ST only. Since
TC3 and ST were regarded as important nursery ground for both horseshoe crab
species, box plots of prosomal width of two horseshoe crab species were
constructed to investigate the changes of population in details.
Box plot of horseshoe crab populations in TC3
3.6.31 Figure
3.6 of Appendix O shows the changes of prosomal width of Carcinoscorpius
rotundicauda and Tachypleus tridentatus in TC3. As mentioned above, Carcinoscorpius
rotundicauda was rarely found between Sep. 2012 and Dec. 2013 hence the
data were lacking. In Mar 2014, the major size (50% of individual records
between upper (top of red box) and lower quartile (bottom of blue box)) ranged
40-60 mm while only few individuals were found. From Mar. 2014 to Jun. 2017,
the median prosomal width (middle line of whole box) and major size (whole box)
decreased after Mar. of every year. It was due to more small individuals found.
It indicated new rounds of spawning. Also there were slight increasing trends
of body size from Jun. to Mar. of next year since 2015. It indicated a stable
growth of individuals. Focused on larger juveniles (upper whisker), the size
range was quite variable (prosomal width 60-90 mm) along the sampling months.
Juveniles reaching this size might gradually migrate to sub-tidal habitats.
3.6.32
For
Tachypleus tridentatus, the major size ranged 20-50 mm while the number
of individuals fluctuated from Sep. 2012 to Jun. 2014. Then a slight but
consistent growing trend was observed from Sep. 2014 to Jun. 2015. The prosomal
width increased from 25-35 mm to 35-65 mm. As mentioned, the large individuals
might have reached a suitable size for migrating from the nursery soft shore to
subtidal habitat. It accounted for the declined population in TC3. From Mar. to
Sep. 2016, slight increasing trend of major size was noticed again. From Dec.
2016 to Jun. 2017, similar increasing trend of major size was noted with much
higher number of individuals. It reflected new round of spawning. In Sep. 2017
(present survey), the major size decreased while the trend was different from
previous two years. Such decline might be the cause of serial cyclone hit between
Jun. and Sep. 2017 (to be discussed in the 'Seagrass survey' section). Across
the whole monitoring period, the larger juveniles (upper whisker) reached 60-80
mm in prosomal width while it could reach 90 mm in present survey. Juveniles
reaching this size might gradually migrate to sub-tidal habitats.
Box plot of horseshoe crab populations in ST
3.6.33 Figure
3.7 of Appendix O shows the changes of prosomal width of Carcinoscorpius
rotundicauda and Tachypleus tridentatus in ST. As mentioned above, Carcinoscorpius
rotundicauda was rarely found between Sep. 2012 and Dec. 2013 hence the
data were lacking. From Mar. 2014 to Sep. 2017, the size of major population
decreased and more small individuals (i.e. lower whisker) were recorded after
Jun. of every year. It indicated new round of spawning. Also there were similar
increasing trends of body size from Sep. to Jun. of next year between 2014 and
2017. It indicated a stable growth of individuals. Across the whole monitoring
period, the larger juveniles (i.e. upper whisker) usually ranged 60-80 mm in
prosomal width except one individual (prosomal width 107.04 mm) found in Mar.
2017. It reflected juveniles reaching this size would gradually migrate to
sub-tidal habitats.
3.6.34 For Tachypleus tridentatus, a consistent growing trend was observed for
the major population from Dec. 2012 to Dec. 2014 regardless of change of search
record. The prosomal width increased from 15-30 mm to 60-70 mm. As mentioned,
the large juveniles might have reached a suitable size for migrating from the nursery
soft shore to subtidal habitat. From Mar. to Sep. 2015, the size of major
population decreased slightly to a prosomal width 40-60 mm. At the same time,
the number of individuals decreased gradually. It further indicated some of
large juveniles might have migrated to sub-tidal habitat, leaving the smaller
individuals on shore. There was an overall growth trend. In Dec. 2015, two big
individuals (prosomal width 89.27 mm and 98.89 mm) were recorded only while it
could not represent the major population. In Mar. 2016, the number of
individual was very few in ST that no boxplot could be produced. In Jun. 2016,
the prosomal width of major population ranged 50-70 mm. But it dropped clearly
to 30-40 mm in Sep. 2016 followed by an increase to 40-50 mm in Dec. 2016,
40-70 mm in Mar. 2017 and 50-60mm in Jun. 2017. Based on overall higher number
of small individuals from Jun. 2016 to Sep. 2017 (present survey), it indicated
new round of spawning. Throughout the monitoring period, the larger juveniles
ranged 60-80 mm in prosomal width. Juveniles reaching this size would gradually
migrate to sub-tidal habitats.
3.6.35
As a summary for horseshoe crab populations in TC3 and ST, there were
spawning of Carcinoscorpius rotundicauda
from 2014 to 2016 while the spawning time should be in spring. There were
consistent, increasing trends of population size in these two sampling zones.
For Tachypleus tridentatus, small
individuals were rarely found in both zones from 2014 to 2015. It was believed
no occurrence of successful spawning. The existing individuals (that recorded
since 2012) grew to a mature size and migrated to sub-tidal habitat. Hence the
number of individuals decreased gradually. In 2016, new round of spawning was
recorded in ST while increasing number of individuals and body size was
noticed.
Impact of the HKLR project
Seagrass Beds
3.6.37
From Sep. to Dec. 2017 (present survey), no seagrass bed was recorded in Tung Chung
Wan. Extensive area of mudflat, where used to be covered by seagrass beds,
re-exposed along TC3 and ST (Figure 3.8
of Appendix O). In the previous survey of Jun. 2017, two species of
seagrass Halophila ovalis and Zostera japonica were recorded in TC3
and ST (Figure 3.9 of Appendix O).
There was still extensive seagrass area (~17046.5 m2) of Halophila ovalis along the mudflat
between TC3 and ST at 0.5-2.0 m above C.D.. Another seagrass species Zostera japonica, which was much lower
in vegetation area (~105.4 m2), was co-existing with few patches of Halophila ovalis nearby the mangrove
strand. The disappearance of seagrass beds would be discussed in later
paragraphs.
3.6.38
According to the
previous results, majority of seagrass bed was confined in ST, the temporal
change of both seagrass species were investigated in details:
Temporal
variation of seagrass beds
3.6.39
Figure 3.10 of Appendix O
shows the changes of estimated total area of seagrass beds in ST along the
sampling months. For Zostera japonica, it was not recorded in the 1st
and 2nd surveys of monitoring programme. Seasonal recruitment of few small patches (total
seagrass area: 10 m2) was found in Mar. 2013 that grew within the
large patch of seagrass Halophila ovalis. Then the patch size
increased and merged gradually with the warmer climate from Mar. to Jun. 2013
(15 m2). However the patch size decreased and remained similar from
Sep. 2013 (4 m2) to Mar. 2014 (3 m2). In Jun. 2014, the
patch size increased obviously again (41 m2) with warmer climate
followed by a decrease between Sep. 2014 (2 m2) and Dec. 2014 (5 m2).
From Mar. to Jun. 2015, the patch size increased sharply again (90 m2).
It might be due to the disappearance of the originally dominant seagrass Halophila ovalis resulting in less competition for substratum and nutrients. From
Sep.2015 to Jun.2016, it was found coexisting with seagrass Halophila ovalis with steady increasing patch size (from 44 m2 to 115 m2) and
variable coverage. In Sep. 2016,
the patch size decreased again to (38 m2) followed by an increase to a horizontal strand (105.4 m2) in Jun. 2017 (present
survey). And it was no longer co-existing with Halophila ovalis. Between Sep. 2014 and Jun. 2017, an increasing trend was noticed from
Sep. to Jun. of next year followed by a rapid decline in Sep. of next year. It
was possibly the causes of heat stress, typhoon and stronger grazing pressure
during wet season. In Sep. and Dec. 2017 (present survey), no seagrass patch of
Zostera japonica was found.
3.6.40
For Halophila
ovalis, it was recorded as 3-4 medium to large patches (area 18.9-251.7 m2; vegetation coverage
50-80%) beside the mangrove vegetation at tidal level 2 m above C.D. in Sep.
2012 (first survey). The
total seagrass bed area grew steadily from 332.3 m2 in Sep. 2012 to
727.4 m2 in Dec. 2013. Flowers were observed in the largest patch
during its flowering period. In Mar. 2014, 31 small to medium patches were newly recorded
(variable area 1-72 m2 per patch, vegetation coverage 40-80% per
patch) in lower tidal zone between 1.0 and 1.5 m above C.D. The total seagrass
area increased further to 1350 m2. In Jun. 2014, these small and
medium patches grew and extended to each other. These patches were no longer
distinguishable and were covering a significant mudflat area of ST. It was generally
grouped into 4 large patches (1116 ¡V 2443 m2) of seagrass beds
characterized of patchy distribution, variable vegetable coverage (40-80%) and
smaller leaves. The total seagrass bed area increased sharply to 7629 m2.
In Sep. 2014, the total seagrass area declined sharply to 1111 m2.
There were only 3-4 small to large patches (6-253 m2) at high tidal
level and 1 large patch at low tidal level (786 m2). Typhoon or strong water current was a possible cause (Fong, 1998). In Sep. 2014,
there were two tropical cyclone records in Hong Kong (7th-8th
Sep.: no cyclone name, maximum signal number 1; 14th-17th
Sep.: Kalmaegi, maximum signal number 8SE) before the seagrass survey dated 21st
Sep. 2014. The strong water current caused by the cyclone, Kalmaegi especially,
might have given damage to the seagrass beds. In addition, natural heat stress
and grazing force were other possible causes reducing seagrass beds area.
Besides, very small patches of Halophila
ovalis could be found in other mud flat area in addition to the recorded
patches. But it was hardly distinguished due to very low coverage (10-20%) and
small leaves.
3.6.41
In Dec. 2014, all the seagrass patches of Halophila ovalis disappeared in ST. Figure 3.10 of Appendix O shows the
difference of the original seagrass beds area nearby the mangrove vegetation at
high tidal level between Jun. 2014 and Dec. 2014. Such rapid loss would
not be seasonal phenomenon because the seagrass beds at higher tidal level (2.0
m above C.D.) were present and normal in December 2012 and 2013. According to
Fong (1998), similar incident had occurred in ST in the past. The original
seagrass area had declined significantly during the commencement of the
construction and reclamation works for the international airport at Chek Lap
Kok in 1992. The seagrass almost disappeared in 1995 and recovered gradually
after the completion of reclamation works. Moreover, incident of rapid loss of
seagrass area was also recorded in another intertidal mudflat in Lai Chi Wo in
1998 with unknown reason. Hence Halophila ovalis was regarded as a short-lived and r-strategy
seagrass that could colonize areas in short period but disappears quickly under
unfavourable conditions (Fong,
1998).
Unfavourable
conditions to seagrass Halophila ovalis
3.6.42
Typhoon or strong water current was suggested
as one unfavourable condition to Halophila
ovalis (Fong, 1998). As mentioned above, there were two tropical cyclone
records in Hong Kong in Sep. 2014. The strong water current caused by the
cyclones might have given damage to the seagrass beds.
3.6.43
Prolonged
light deprivation due to turbid water would be another unfavouable condition.
Previous studies reported that Halophila ovalis had little tolerance to
light deprivation. During experimental darkness, seagrass biomass declined rapidly
after 3-6 days and seagrass died completely after 30 days. The rapid death
might be due to shortage of available carbohydrate under limited photosynthesis
or accumulation of phytotoxic end products of anaerobic respiration (details
see Longstaff et al., 1999). Hence the seagrass bed of this species was
susceptible to temporary light deprivation events such as flooding river runoff
(Longstaff and Dennison, 1999).
3.6.44 In
order to investigate any deterioration of water quality (e.g. more turbid) in
ST, the water quality measurement results at two closest monitoring stations
SR3 and IS5 of the EM&A programme were obtained from the water quality
monitoring team. Based on the results from June to December 2014, the overall
water quality was in normal fluctuation except there was one exceedance of
suspended solids (SS) at both stations in September. On 10th Sep.,
2014, the SS concentrations measured during mid-ebb tide at stations SR3 (27.5
mg/L) and IS5 (34.5 mg/L) exceeded the Action Level (≤23.5 mg/L and 120% of
upstream control station¡¦s reading) and Limit Level (≤34.4 mg/L and 130% of
upstream control station¡¦s reading) respectively. The turbidity readings at SR3
and IS5 reached 24.8-25.3 NTU and 22.3-22.5 NTU respectively. The temporary
turbid water should not be caused by the runoff from upstream rivers. Because
there was no rain or slight rain from 1st to 10th Sep. 2014 (daily total
rainfall at the Hong Kong International Airport: 0-2.1 mm; extracted from the
climatological data of Hong Kong Observatory). The effect of upstream runoff on
water quality should be neglectable in that period. Moreover the exceedance of
water quality was considered unlikely to be related to the contract works of
HKLR according to the ¡¥Notifications of Environmental Quality Limits
Exceedances¡¦ provided by the respective environmental team. The respective
construction of seawall and stone column works, which possibly caused turbid
water, were carried out within silt curtain as recommended in the EIA report.
Moreover there was no leakage of turbid water, abnormity or malpractice
recorded during water sampling. In general, the exceedance of suspended solids
concentration was considered to be attributed to other external factors, rather
than the contract works.
3.6.45 Based
on the weather condition and water quality results in ST, the co-occurrence of cyclone hit and turbid waters in Sep. 2014 might
have combined the adverse effects on Halophila
ovalis that leaded to
disappearance of this short-lived and r-strategy
seagrass species. Fortunately Halophila ovalis was a fast-growing
species (Vermaat et al., 1995). Previous studies showed that the
seagrass bed could be recovered to the original sizes in 2 months through
vegetative propagation after experimental clearance (Supanwanid, 1996). Moreover
it was reported to recover rapidly in less than 20 days after dugong herbivory
(Nakaoka and Aioi, 1999). As mentioned, the disappeared seagrass in ST in 1995
could recover gradually after the completion of reclamation works for
international airport (Fong, 1998). The seagrass beds of Halophila
ovalis might recolonize the mudflat of ST through seed reproduction as long
as there was no unfavourable condition in the coming months.
Recolonization
of seagrass beds
3.6.46 Figure 3.10 of Appendix O shows the recolonization of seagrass bed area in ST from Dec. 2014 to Jun.
2017. From Mar. to Jun. 2015, 2-3
small patches of Halophila ovalis were newly
found coinhabiting with another seagrass species Zostera
japonica. But its total patch area was still very low relative to
the previous records. The recolonization rate was low while cold weather and
insufficient sunlight were possible factors between Dec. 2014 and Mar. 2015. Moreover,
it would need to compete with seagrass Zostera
japonica for substratum and nutrient. Since Zostera japonica had extended and had
covered the original seagrass bed of Halophila ovalis at certain degree. From
Jun. 2015 to Mar. 2016, the total seagrass area of Halophila ovalis had increased rapidly from 6.8 m2 to 230.63 m2. It had recolonized its original patch
locations and covered Zostera japonica.
In Jun. 2016, the total seagrass area
increased sharply to 4707.3 m2. Similar to the previous records of Mar to Jun. 2014, the original
patch area increased further to a horizontally long strand. Another large
seagrass beds colonized the lower
tidal zone (1.0-1.5 m above C.D.). In Sep. 2016, this patch extended much and
covered significant soft mud area of ST, resulting in sharp increase of total
area (24245 m2). It indicated the second extensive colonization of
this r-strategy seagrass. In
Dec. 2016, this extensive seagrass patch decreased in size and had separated into few, undistinguishable
patches. Moreover, the horizontal strand nearby the mangrove vegetation
decreased in size (Fig. 3.10). The total seagrass bed decreased to 12550 m2.
From Mar. to Jun. 2017, the seagrass bed area remained generally stable
(12438-17046.5 m2) but the vegetation coverage fluctuated (20-50% in
Mar. 2017 to 80-100% in Jun. 2017).
Re-disappearance
of seagrass bed
3.6.47 In Jun 2017, the whole seagrass bed of Halophila ovalis disappeared again along
the shore of TC3 and ST (Figure 3.10 of
Appendix O). It was similar to the case between Sep. and Dec. 2014. As
mentioned, strong water current (e.g. cyclone) or deteriorated water quality
(e.g. high turbidity) were the possible causes.
3.6.48 Between the survey periods of Jun. and Sep. 2017,
there were four tropical cyclone records in Hong Kong (Merbok in 12-13th,
Jun.; Roke in 23rd, Jul.; Hato in 22-23rd, Aug.; Pakhar
in 26-27th, Aug.) (online database of Hong Kong Observatory). All of
them reaches signal 8 or above especially Hato (highest signal 10).
3.6.49 According to the water quality monitoring results
(Jul. to Aug. 2017) of the two closest monitoring stations SR3 and I5 of the
respective EM&A programme, the overall water quality was in normal
fluctuation. There was one exceedance of suspended solids (SS) at SR3 on 12 Jul.
2017. The SS concentration reached 24.7 mg/L during mid-ebb tide. It exceeded
the Action Level (≤23.5 mg/L) but
was far below the Limit Level (≤34.4 mg/L).
Since such exceedance was slight and temporary, its effect to seagrass bed
should be minimal.
3.6.50 Overall, the disappearance of seagrass beds in ST was
believed the cause of serial cyclone hit in Jul and Aug. 2017. Based on
previous findings, the seagrass beds of both species were expected to
recolonize the mudflat as long as the vicinal water quality was normal. The
recolonization would be a gradual process lasting for about 1.5 years. In Dec.
2017 (present survey), there was no recolonization recorded.
Impact
of the HKLR project
3.6.51 It
was the 21st survey of the EM&A programme during the
construction period. According to the results of present survey, the
disappearance of seagrass beds was believed the cause of serial cyclone hits
rather than impact of HKLR project. Based on previous findings, the seagrass
beds were expected to recolonize the mudflat gradually in the future, as long
as the vicinal water quality remained normal.
Intertidal Soft
Shore Communities
3.6.52
Table 3.2 and Figure 3.12
of Appendix O show the types of
substratum along the horizontal transect at every tidal level in all sampling
zones. The relative distribution of different substrata was estimated by
categorizing the substratum types (Gravels & Boulders / Sands / Soft mud)
of the ten random quadrats along the horizontal transect. The distribution of
substratum types varied among tidal levels and sampling zones:
¡P
In TC1, even distribution of ¡¥Gravels and
Boulders¡¦ (50%) and ¡¥Sands¡¦ (50%) were recorded at high tidal level. High
percentages of ¡¥Gravels and Boulders¡¦ (80-90%) was recorded at mid and low
tidal levels followed by ¡¥Sands¡¦ (10-20%).
¡P
In TC2, high percentages of 'Sands' (40%) and
'Soft mud' (40%) were recorded at high tidal level. At mid tidal level, the
major substratum type was 'Soft mud' (80%) followed by 'Gravels and Boulders'
(20%). At low tidal level, the major substratum type was 'Soft mud' (90%).
¡P
In TC3, high percentage of ¡¥Sands¡¦ (80%) was
recorded at high tidal level. But even distirbution of substratum types were
recorded at mid tidal level (¡¥Sands¡¦ (50%), ¡¥Soft mud¡¦ (30%), ¡¥Gravels and Boulders¡¦
(20%)). At low tidal level, the major substratum type was ¡¥Gravels and
Boulders¡¦ (90%).
¡P
In ST, ¡¥Gravels and Boulders¡¦ was the main
substratum (70-90%) at high and mid tidal levels. At low tidal level, the
substartum types were mainly ¡¥Soft mud¡¦ (60%) and 'Sands' (30%).
3.6.53
There was neither consistent vertical nor horizontal zonation pattern of
substratum type in all sampling zones. Such heterogeneous variation should be
caused by different hydrology (e.g. wave in different direction and intensity)
received by the four sampling zones.
3.6.54
Table 3.3 of Appendix O lists the total abundance, density and number of taxon of every phylum
in this survey. A total of 10055 individuals were
recorded. Mollusca was clearly the most
abundant phylum (total abundance 9796 ind., density 327 ind. m-2, relative abundance
97.4%). The second to fourth abundant phya were Arthropoda (182 ind., 6 ind. m-2, 1.8%), Annelida (45 ind., 2 ind. m-2, 0.4%) and Sipuncula (16 ind., 1 ind. m-2, 0.2%) respectively. Relatively other phyla were very low in abundances (density £1 ind. m-2,
relative abundance £0.2%). Moreover, the most diverse phylum was Mollusca (37 taxa) followed by Arthropoda (13 taxa) and Annelida (9 taxa). There was 1-2 taxa recorded only for other phyla. The taxonomic resolution and complete list of
collected specimens are shown in Annexes IV and V of Appendix O
respectively.
3.6.55
Table 3.4 of Appendix O shows the number of individual, relative abundance and density of each phylum in every sampling zone. The total abundance (1211-4768 ind.) varied among the four sampling
zones while the phyla distributions were similar. In
general, Mollusca was the most
dominant phylum (no. of individuals: 1103-4704 ind.; relative
abundance 91.1-98.7%; density 147-627 ind. m-2). Other phyla were much lower in number of individuals. Arthropoda (12-87 ind.; 0.8-7.2%; 2-12 ind. m-2) and Annelida (7-18 ind.; 0.2-1.5%; 1-2 ind. m-2) were the second
and third abundant phyla. Sipuncula was relatively common in TC3 (9 ind.; 0.3%; 1 ind. m-2).
Relatively other phyla were very low in abundance in all
sampling zones.
Dominant species in every
sampling zone
3.6.56 Table 3.5 of Appendix O lists the abundant species (relative abundance >10%) in every
sampling zone. In the present survey, most
of the listed abundant species were of low to moderate densities (50-250 ind. m-2).
Few listed species of high or very high density (> 250 ind. m-2)
were regarded as dominant species. Other listed species of lower density (<
50 ind. m-2) were regared as common species.
3.6.57 In TC1, the substratum
was either ¡¥Gravels
and Boulders¡¦ or 'Sands' at high tidal level. It was dominanted by gastropod Batillaria
multiformis (816 ind. m-2,
relative abundance 84%) at very high density. At mid tidal level (substratum
type ¡¥Gravels
and Boulders¡¦), it was also dominated by gastropod Batillaria
multiformis (295 ind. m-2,
55%) at high density. Other moderately abundant species were gastropod Monodonta
labio (89
ind. m-2, 17%) and rock oyster Saccostrea
cucullata (66 ind. m-2, 12%, attached on boulders). At low tidal
level (substratum type ¡¥Gravels
and Boulders¡¦), abundant rock oyster Saccostrea
cucullata (135 ind. m-2, 34%) were attaching on the boulders
followed by gastropod Monodonta labio (96 ind. m-2, 24%).
3.6.58 In TC2, there was no clearly abundant species at all tidal levels. At high tidal level, rock oyster Saccostrea cucullata (88 ind. m-2, 36%,
attached on boulders) was relatively abundant followed by common gastropods Cerithidea
djadjariensis (47 ind. m-2,
19%), Batillaria zonalis (39
ind. m-2, 16%) and Batillaria
multiformis (24 ind. m-2, 10%). At mid and low tidal levels,
gastropod Batillaria zonalis (22-59
ind. m-2, 28-37%) and rock oyster Saccostrea
cucullata (18-41 ind. m-2, 23-25%) were common species.
Moreover, barnacle Balanus amphitrite (21 ind. m-2, 27%, attached on boulders) was also common at low
tidal level.
3.6.59
In TC3, the major
substratum types were either ¡¥Sands¡¦ and 'Soft mud' at both high and mid tidal
levels. Gastropods Cerithidea
djadjariensis (47-112 ind. m-2,
20-40%) and Batillaria multiformis (98-106 ind. m-2, 38-42%)
were abundant at low to moderate densities. Besides gastropods Cerithidea
cingulata (39 ind. m-2, 14%) and Batillaria zonalis (28 ind. m-2, 12%) were
common species at high and mid tidal levels respectively. At low tidal level (major substratum: ¡¥Gravels and Boulders¡¦), rock oyster Saccostrea cucullata (240 ind. m-2, 44%) and gastropod
Monodonta labio (171
ind. m-2, 31%) were abundant at moderate densities.
3.6.60 In ST, there was no
clearly abundant species at all tidal levels. At high and mid tidal levels
(major substratum type: 'Gravels
and Boulders¡¦), gastropods Monodonta labio (41-74 ind. m-2,
17-31%), Lunella coronata (35-66 ind. m-2, 15-27%) and rock oyster Saccostrea cucullata (52-90 ind. m-2,
22-36%, attached on boulders) were common or abundant species at low densities.
Besides gastropod Batillaria multiformis (32 ind. m-2, 14%)
was also common at high tidal level. At low tidal level (major substratum type: ¡¥Soft mud¡¦), there
were two common taxa including rock oyster Saccostrea
cucullata (46
ind. m-2, 51%) and gastropod Batillaria
zonalis (9 ind. m-2, 10%)
3.6.61
In general, there was no consistent zonation pattern of species distribution across all sampling zones and tidal levels. The species
distribution should be determined by the type of substratum primarily. In general, gastropods Batillaria multiformis (total number of individuals: 3588 ind.,
relative abundance 35.7%), Cerithidea djadjariensis (776 ind., 7.7%), Batillaria zonalis (457 ind., 4.5%) and Cerithidea cingulata (404 ind., 4.0%) were the most commonly
occurring species on sandy and soft mud substrata. Rock oyster Saccostrea cucullata (2000 ind., 19.9%), gastropods Monodonta
labio (1335 ind., 13.3%) and Lunella coronata (454
ind., 4.5%) were commonly occurring species inhabiting
gravel and boulders substratum.
Biodiversity
and abundance of soft shore communities
3.6.62
Table 3.7 of Appendix O shows the mean values of species number, density, biodiversity index H¡¦ and species evenness J of soft shore communities at every tidal level and in every sampling zone. As mentioned above, the differences among sampling zones and tidal
levels were determined by the major type of substratum primarily.
3.6.63
Among the sampling zones, there was no obvious difference of mean species number, H' and J across all tidal levels. The mean species numbers ranged 6-10
spp. 0.25 m-2 among all sampling zones. The mean densities of TC1
(636 ind. m-2) were higher than TC3 (352 ind. m-2)
followed by TC2 and ST (161-191 ind. m-2). TC1 was much higher in
mean density but it was mainly accounted by one gastropod
species of high abundance at high tidal level. Overall the mean H¡¦ and J were similar, that ranged 1.2-1.3 and
0.6-0.8 respectively among all sampling zones.
3.6.64
Across the tidal levels, there was no consistent difference of the mean species number, H' and J in all sampling zones. For the mean density, there were generally
decreasing trends in TC1, TC2 and ST from high to low tidal level but vice
versa in TC3. But there was no clear correlation with other environmental
factors.
3.6.65
Figures 3.13 to
3.16 of Appendix O show the temporal changes of mean species number, mean density, H¡¦ and J at every tidal level and in every sampling zone along the sampling months. In general, all the biological parameters
fluctuated seasonally throughout the monitoring period. Lower mean species
number and density were recorded in dry season (Dec.) but the mean H' and J fluctuated within a stable range.
3.6.66
Different from previous monitoring report, there were steady decreasing
trends of mean species number and density in TC2, TC3 and ST since Jun. 2017
regardless of tidal levels. It might be an unfavourable change reflecting
environmental stresses. The heat stress and serial cyclone hit were believed
the causes during the wet season of 2017. Recently it was expected that the
intertidal community would recover gradually in the following wet season (e.g.
Mar-Jun. 2018). More consolidated discussion might be given after the next
monitoring.
Impact of the HKLR
project
Table 4.1 A
Summary of Environmental Complaint for the Reporting Period
Environmental Complaint No. |
Date of Complaint Received |
Description of Environmental Complaint |
COM-2017-129 |
ENPO¡¦s email to the Supervising
Officer¡¦s Representative and Contractor on 8 January 2018 that HyD received
a complaint lodged by a member of the public regarding cleanliness problem
at East Coast Road on 29 December 2017 |
Cleanliness problem at East Coast Road |
COM-2018-132 |
HyD (SOR
referred the email from HyD to Contractor and ET on 13 February 2018) and
EPD (ENPO referred the email from EPD to SOR, SOR sent the email to
Contractor and ET on 14 February 2018)
|
Complaint about Dust, Water Quality, Construction Waste, Noise and
Vibration for the Contract |
¡P
The Contractor was
reminded to ensure the mechanical cover of the dump truck closed during
transportation of materials at HMA.
¡P
The Contractor was
reminded to carry out loading, unloading, transfer, handing or storage of bulk
cement in an enclosed system at S15.
¡P
The Contractor was
reminded to water the stockpile during excavation at S16.
¡P
The Contractor was
reminded to prevent vehicles to bring mud out of site area at N26.
¡P
The Contractor was
reminded to spray water on the haul road/access road to prevent dust emission
at N20A, N26, S16 and S22.
¡P
The Contractor was
reminded to stop the water discharge and remove the blue hose at plant room of
S15.
¡P
The Contractor was
reminded to take measures to prevent wastewater from the site entering into
marine water at S7.
¡P
The Contractor was
reminded to provide washing facilities for cleaning the vehicles before leave
the work area at S16 and N30.
¡P
The Contractor was
reminded to maintain the silt curtains properly at Portion X.
¡P
The Contractor was
reminded to remove the stagnant water and apply larvicide at plant room of S15.
¡P
The Contractor was
reminded to remove the stagnant water at S16.
¡P
The Contractor was
reminded to remove stagnant water from the drip tray next to the generator at
S16.
¡P
The Contractor was
reminded to remove/ dispose of the concrete waste regularly at WA4.
¡P
The Contractor was
reminded to dispose of the general refuse at West Portal.
¡P
The Contractor was
reminded to remove construction waste from HAT, N1, N20, S9, S15, S16, S25,
Plant room of S15 and Depressed Roundabout of S16.
¡P
The Contractor was
reminded to remove the abandoned cement bags at S16.
¡P
The Contractor was
reminded to provide drip tray for the chemical containers at HAT, N26, N30,
depressed roundabout of N30, S7, S9 and S16.
¡P
The Contractor was
reminded to remove the abandoned chemical containers at HAT.
¡P
The Contractor
provide drip tray for the oil drums at N26, N30 and Depressed Roundabout of
S16.
¡P
The Contractor was
reminded to remove the oil stain and treat as chemical waste at S9, S25 and
WA4.
¡P
The Contractor was
reminded to clear the chemicals inside the drip tray and treat it as chemical
waste at S15.
Environmental
Site Inspection and Audit