Contents
1.1 Purpose of the Report
1.2 Structure of the Report
2.1 Background
2.2 Site Description
2.3 Status of Environmental Approval Documents
3 Water
Quality Monitoring Requirements
3.1 Monitoring Locations
3.2 Monitoring Parameters
3.3 Monitoring Equipment and Methodology
4 Implementation
Status of Environmental Mitigation Measures
5 Post
Project Monitoring Results
LIST
OF TABLES
Table
2.1 Summary of Environmental Licensing,
Notification, Permit and Reporting Status
Table
3.1 Water Quality Impact Stations
Table
3.2 Equipment Used during the Post Project
Water Quality Monitoring
LIST
OF ANNEXES
|
Annex A |
|
|
Annex B |
|
|
Annex C |
|
|
Annex D |
The
submarine cable installation works for the Asia Submarine-cable Express (ASE)
cable system commenced in January 2014 and were completed in February 2014. This is the Post Project Water Quality Monitoring Report (Zone A) presenting results and
findings of the post project water quality monitoring conducted during the
period from 10 to 15 March 2014 in accordance with the Updated Environmental Monitoring
and Audit Manual (Updated
EM&A Manual).
Water Quality
Three monitoring events (days) were
scheduled between 10 and
15 March 2014, at monitoring
stations located in Zone A, to replicate monitoring activities conducted for
baseline data gathering in accordance with the Updated EM&A Manual. Monitoring events at all designated
monitoring stations in Zone A were performed on schedule.
In general, the Dissolved Oxygen (DO) levels
recorded during the post project monitoring period were recorded mostly higher than
results obtained during the baseline update monitoring period. Turbidity and Suspended Solid (SS) levels
observed in the post project monitoring period were observed lower than the
results recorded during the baseline update monitoring period at all designated
stations. After detailed analyses,
it is considered that the overall changes in DO, Turbidity and SS were driven
by natural fluctuations.
Conclusion
Upon
completion of the cable installation, the overall water quality at the impact
stations in Zone A was found similar to that at the control station and was
recorded higher in DO and lower in Turbidity and SS when compared with the
baseline data. Given the fact that
the control station is sufficiently far away from the cable alignment and water
quality at this station could not be affected by the Project, it is concluded that
the overall changes in DO, Turbidity and SS levels during
the post-project monitoring period at all designated stations including the
control station are likely to represent a natural phenomenon. It is considered
that no deterioration of water quality was observed and the impacts from the Project
works on water quality are negligible.
ERM-Hong
Kong, Limited (ERM) was appointed by NTT Com Asia (NTTCA) as the Environmental Team (ET) to
implement the Environmental Monitoring and Audit (EM&A) programme for the re-installation
of a damaged section of the Asia-Submarine-cable Express (ASE) telecommunication
cable (thereinafter called the “Project”). The ASE cable is approximately
7,200 km in length, connecting Japan and Singapore with branches to the
Philippines, Hong Kong SAR (HKSAR) and Malaysia.
This
is the
Post Project Water Quality
Monitoring Report (Zone A),
which summarises the results of post project water quality monitoring as part
of the EM&A programme during the reporting period from 10 to 15 March 2014. The post
project monitoring results have been compared to the baseline water quality update
monitoring results in order to investigate any impact of the Project marine works
on water quality in the vicinity of the Project site.
The
structure of the Report is as follows:
Section
1 : Introduction
Provides
details of the background, purpose and report structure.
Section
2 : Project Information
Summarises
background and scope of the project, the repair works undertaken and the status
of Environmental Permits/Licenses during the reporting period.
Section
3 : Water Quality Monitoring
Requirements
Summarises the monitoring
parameters, monitoring programmes, monitoring methodologies, monitoring
frequency, and monitoring locations.
Section
4 : Implementation Status of
Environmental Mitigation Measures
Summarises
the implementation of environmental protection measures during the reporting
period.
Section
5 : Post Project Monitoring
Results
Summarises the
monitoring results obtained in the reporting period for Zone A.
Section
6 : Conclusions
Presents the key findings of the post
project monitoring results.
In
2012/2013, NTT Com Asia (NTTCA) installed a telecommunication cable (Asia
Submarine-cable Express (ASE) cable) of approximately 7,200 km in length,
connecting Japan and Singapore with branches to the Philippines, Hong Kong SAR
(HKSAR) and Malaysia, with marine works in HK waters initially completed in
January 2013. NTTCA was also
responsible for securing the approval to land the ASE cable in Tseung Kwan O, Hong
Kong SAR (HKSAR), the landing site for a number of submarine cables, and the
landing site is at a Beach Manhole (BMH) after which the cable ultimately connects
with a Data Centre in Tseung Kwan O (TKO) Industrial Estate. .
From Tseung Kwan O, the cable extends westward approaching the Tathong
Channel. Near to Cape Collinson,
the cable is approximately parallel to the Tathong Channel until north of
Waglan Island where it travels eastward to the boundary of HKSAR waters and
enters the South China Sea. The
total length of cable in Hong Kong SAR waters is approximately 33.5 km. A map of the cable route is presented in
Figure
2.1.
A
Project Profile (PP-452/2011) which includes an assessment of the potential
environmental impacts associated with the installation of the submarine
telecommunications cable system was prepared and submitted to the Environmental
Protection Department (EPD) under section 5.(1) (b) and 5.(11) of the Environmental Impact Assessment Ordinance
(EIAO) for the application for Permission to apply directly for Environmental
Permit (EP). EPD subsequently
issued an Environmental Permit (EP-
433/2011).
Pursuant
to Condition 2.4 of EP- 433/2011, an environmental monitoring and audit (EM&A)
programme, as set out in the Environmental
Monitoring and Audit Manual (EM&A Manual([1])) is required for this Project. Baseline data were collected prior to
the start of cable installation works in 2012 and EM&A was conducted
throughout the cable installation and after its completion in early 2013. as
required in the EM&A Manual.
Upon
inspection in October 2013 the ASE cable was found to be damaged and a section
within Zone A (see Figure 2.2) required re-installation. The EM&A
programme are therefore required to resume for the cable installation works in
Hong Kong Waters and the EM&A Manual was
updated to reflect these new repair works and produce the
Updated EM&A Manual.
New baseline water quality ‘update’
monitoring was conducted prior to the start of re-installation works, in early
November 2013, and results are summarised in the ‘Baseline Water Quality Monitoring Update Report
(Zone A)’of December 2013.
Impact monitoring started on 12
January 2014, when the cable re-installation works commenced in Zone A. The initial cable installation works
were completed on 5 February 2014 and the impact water quality monitoring
ceased subsequently. The impact
water quality monitoring results were summarized in the following reports:
·
2014 First Weekly
Impact Water Quality Monitoring Report (Zone A);
·
2014 Second Weekly
Impact Water Quality Monitoring Report (Zone A);
·
2014 Third Weekly
Impact Water Quality Monitoring Report (Zone A); and
·
2014 Forth Weekly
Impact Water Quality Monitoring Report (Zone A).
All marine works for the cable repair works were completed
in early February 2014 and
final confirmation of completion of the work after testing of the cable was
given on Tuesday 4 March 2014. In accordance with the Updated EM&A Manual, post project water quality monitoring should comprise
sampling on three occasions (days) within three weeks of completion of the
marine installation works.
This Post Project Water Quality Monitoring Report (Zone A) presents the results
and findings from the 2014 post project monitoring, conducted in the monitoring
period 10-15 March 2014. It should be noted that cable repair works were only
carried out in Zone A (Cape Collinson) and results of the post project monitoring
data have therefore been compared against the results of the baseline water
quality update monitoring in Zone A.
The
cable installation works for the damaged section of the ASE cable were
conducted near TKO in Zone A (Figure 2.2).
A summary of the relevant permits,
licences and reports on marine water quality for this Project is presented in Table 2.1.
Table 2.1 Summary
of Environmental Licensing, Notification, Permit and Reporting Status
|
Permit / Licence / Notification /
Report |
Reference |
Validity Period |
Remarks |
|
Environmental Permit |
EP 433/2011 |
Throughout the
construction and operation stages |
Granted on 20 December 2011 |
|
EM&A Manual |
- |
Throughout the
construction and operation stages |
Submitted
on 18 September 2012. Superseded
by Updated EM&A Manual |
|
Updated
EM&A Manual |
- |
Throughout the
construction and operation stages |
Submitted
in December 2013 |
|
Baseline Water Quality
Monitoring Update Report (Zone A) |
- |
n/a |
Submitted
on 5 December 2013 |
|
2014
First Weekly Impact Water Quality Monitoring Report (Zone A) |
|
n/a |
Submitted on 23
January 2014 |
|
2014
Second Weekly Impact Water Quality Monitoring Report (Zone A) |
|
n/a |
Submitted on 30
January 2014 |
|
2014
Third Weekly Impact Water Quality Monitoring Report (Zone A) |
|
n/a |
Submitted on 6 February
2014 |
|
2014
Forth Weekly Impact Water Quality Monitoring Report (Zone A) |
|
n/a |
Submitted on 12 February 2014 |
In accordance with the Updated EM&A Manual,
water quality monitoring samples were collected at eleven (11) stations, the same stations as
baseline monitoring situated around the cable installation works in
Zone A. The
locations of the sampling stations within Zone A are shown in Figure 2.2.
· E7
is the Impact Station located at Fat Tong Chau to monitor the impacts of cable
installation works on the coral communities in the proximity;
· E8
is an Impact Station to monitor the impacts of cable installation works on the
coral communities along Junk Bay – South West;
· E9
is an Impact Station to monitor the impacts of cable installation works on the
coral communities at Cape Collison (the Gradient Station is not set due to the
short distance of this Impact Station to nearby proposed cable works which may
affect the Project marine installation works);
· F1
is an Impact Station to monitor the impacts of cable installation works on the
Tung Lung Chau Fish Culture Zone;
· S1
is an Impact Station situated at the WSD Seawater Intake Point in Junk
Bay. It is located within 500 m
north of the cable alignment at Junk Bay and set up to monitor the effect of Project
marine installation
works in the area;
· S2
is an Impact Station to monitor the impacts of cable installation works on the
WSD Seawater Intake at Siu Sai Wan;
· S3
is an Impact Station to monitor the impacts of cable installation works on the
Pamela Youde Nethersole Eastern Hospital Cooling Water Intake at Heng Fa Chuen;
· G1
is a Gradient Station between S1 and the cable alignment;
· G2
is a Gradient Station between S2 and the cable alignment;
· G3
is a Gradient Station between F1 and the cable alignment; and
· C1
is a Control Station (approximately 3 km from the proposed cable alignment) for
Zone A. It is not supposed to be
influenced by the Project marine installation works due to its remoteness from the works.
The co-ordinates of the above
monitoring stations in Zone A are listed in Table 3.1.
Table 3.1 Water
Quality Monitoring Stations
|
Monitoring
Station |
Nature |
Easting |
Northing |
|
E7 |
Impact
Station (Coral Community) |
843779 |
814520 |
|
E8 |
Impact
Station (Coral Community) |
843111 |
815126 |
|
E9 |
Impact
Station (Coral Community) |
843557 |
811853 |
|
F1 |
Impact Station (Fish Culture Zone) |
847196 |
811056 |
|
S1 |
Impact Station (Seawater Intakes) |
847639 |
805900 |
|
S2 |
Impact Station (Seawater Intakes) |
849587 |
805696 |
|
S3 |
Impact Station (Seawater Intakes) |
845474 |
810605 |
|
G1 |
Gradient
Station |
845297 |
816282 |
|
G2 |
Gradient
Station |
844071 |
814784 |
|
G3 |
Gradient
Station |
846099 |
812826 |
|
C1 |
Control
Station |
842022 |
816547 |
The post project water quality
monitoring was conducted in accordance with the requirements stated in the Updated EM&A Manual. Monitoring
parameters are presented as below.
Parameters measured in situ were:
·
Dissolved Oxygen (DO) (%
saturation and mg L-1);
·
Temperature (°C);
·
Turbidity (NTU); and
·
Salinity (‰).
The only parameter measured in the laboratory was:
·
Suspended Solids (SS) (mgL-1).
In addition to the water quality parameters, other
relevant data were measured and recorded in field logs, including the location
of the sampling stations, water depth, time, weather conditions, sea
conditions, special phenomena and work activities undertaken around the
monitoring and works area that may influence the monitoring results.
Table
3.2 summaries the
equipment used for the post project water quality monitoring.
Table
3.2 Equipment Used during the Post Project
Water Quality Monitoring
|
Equipment |
Model |
|
Global
Positioning Device |
Garmin
etrex 10 |
|
Water
Depth Gauge |
Speedtech
Instrument SM-5 |
|
Water
Sampling Equipment |
1520
Kemmerer Water Sampler |
|
Salinity,
DO, Temperature Measuring Meter |
YSI
Pro 2030 |
|
Current
Velocity and Direction |
Flow
Probe FP11 |
|
Turbidity Meter |
HACH Model 2100Q Turbid Meter |
The water monitoring was carried out on three occasions
(days) and the intervals between two sets of monitoring were not less than 36
hours. The water quality sampling was
undertaken within a 4 hour window of 2 hour before and 2 hour after mid flood
and mid-ebb tides. The
tidal range selected for the post project monitoring was at least 0.5 m for
both flood and ebb tides as far as practicable.
Reference were made to the predicted tides at Tai Miu
Wan, which is the tidal station nearest to the Project Site, published on the
website of the Hong Kong Observatory ([2]). Based on
the predicted tidal levels at Tai Miu Wan, the post-project water quality
monitoring was conducted between 10 and 15 March 2014, following the schedule
presented in Annex A.
Each station was sampled
and measurements/ water samples were taken at three depths, namely, 1 m below
water surface, mid-depth and 1 m above sea bed, except where the water depth
less than 6 m, the mid-depth station may be omitted. For stations that are less than 3 m in
depth, only the mid-depth sample was taken.
For in situ measurements, duplicate readings were made at each water
depth at each station. Duplicate
water samples were collected at each water depth at each station.
All in situ
monitoring instruments were checked, calibrated and certified by a laboratory
accredited under HOKLAS or any other international accreditation scheme before
use (see calibration reports in Annex
B), and
subsequently will be re-calibrated at monthly intervals throughout all stages
of the water quality monitoring. Responses
of sensors and electrodes were checked with certified standard solutions before
each use.
For the on-site calibration of field equipment, the BS 1427: 1993, Guide to Field and On-Site
Test Methods for the Analysis of Waters was observed. Sufficient stocks of spare parts were
maintained for replacements when necessary. Backup monitoring equipment was made
available.
Water samples for SS measurements were collected in
high density polythene bottles, packed in ice (cooled to 4°C without being
frozen), and delivered to a HOKLAS laboratory as soon as possible after
collection.
Two replicate samples were collected from each of the
monitoring events for in situ
measurement and lab analysis.
All laboratory work was carried out in
a HOKLAS accredited laboratory.
Water samples of about 1,000 mL were collected at the monitoring and
control stations for carrying out the laboratory determinations. The determination work started within
the next working day after collection of the water samples. The SS laboratory measurements were
provided within 2 days of the sampling event (48 hours). The analyses followed the standard
methods as described in APHA Standard Methods for the Examination of Water and Wastewater, 19th Edition, unless otherwise specified (APHA 2540D for SS).
The QA/QC details were in accordance
with requirements of HOKLAS or another internationally accredited scheme (Annex B).
Mitigation measures for water quality
control were recommended in the Project Profile (PP-452/2011) and Environmental
Permit (EP- 433/2011). The
Contractor implemented the following select and relevant mitigation measures
during cable re-installation works:
·
The forward speed of the
installation barge was limited to a maximum of 1 km/ hour;
·
Water quality monitoring was
carried out to verify that the project works were not resulting in any impacts
to water quality, marine ecology and fisheries; and
·
Prevention of leakage from
construction equipment to reduce the runoff entering the marine waters was
incorporated as part of good working practices.
A total of three (3) monitoring events (days) were
scheduled in the monitoring period from
10 to 15 March 2014 (Annex
A).
Monitoring occasions at all designated monitoring stations within Zone A (conducted on 10, 13 and 15 March 2014) were performed on schedule. No major activities influencing the
water quality were identified during the reporting period.
The
post project monitoring data are presented in Annex D and have been compared with baseline update
monitoring results.
The
levels of DO measured during the post project monitoring period at different
sampling depths were generally higher than those obtained during the baseline update
monitoring period (Figure D1-D3). Elevation of DO concentration was
detected at all the impact stations and the control station C1 (situated a long
distance from the submarine cable alignment and not likely to be affected by
the Project works) during the post project monitoring period. DO levels recorded at the impact
stations were of similar magnitude to those measured at the control station C1.
Levels
of Turbidity and SS measured during the post project monitoring period were generally
lower compared to those measured during the baseline update monitoring period (Figure D4-D5). This occurred to all the monitoring
stations including the control station C1, which is situated a long distance
from the submarine cable alignment and not likely to be affected by the Project
works. Turbidity and SS levels recorded
at all the impact stations were generally of similar magnitude to those
measured at the control station C1 during post project monitoring period. Replicated data at impact and control
stations indicates that the situation was due to natural fluctuations.
Given
the above information, particularly with regard to the control station, the
overall changes in DO, Turbidity and SS levels during the post project monitoring
period at all designated stations compared to baseline data are likely to represent
a natural phenomenon.
This
Post Project Water Quality Monitoring
Report (Zone A) presents the
EM&A work undertaken during the period from 10 to 15 March 2014 in
accordance with the Updated EM&A
Manual and the requirements under Environmental Permit (EP- 433/2011).
Post
project water quality monitoring in Zone A was conducted within 3 weeks of
confirmation that the marine cable repair works had been completed. The overall water
quality at the impact stations in Zone A was found to be similar to that at the
control station with higher DO levels and lower Turbidity and SS levels recorded
compared to the updated baseline data.
Given the fact that the control station is sufficiently far away from
the cable alignment and water quality at this station could not be affected by
the Project, it is concluded that the
overall changes in DO, Turbidity and SS levels during the post-project
monitoring period at all designated stations including the control station are
likely to represent natural variation.
It
is considered that no deterioration of water quality was observed between post
project and baseline monitoring for this cable repair work and therefore the Project
works had negligible impact on water quality.
([2]) Hong
Kong Observatory (2013) http://www.hko.gov.hk/tide/eQUBtide.htm
[Accessed in February 2013]