1
introduction
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 telecommunication cable
(Asia-Submarine-cable Express (ASE)). 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
(thereinafter called the Project).
This
is the
First Weekly
Impact Water Quality Monitoring Report,
which summarises the results of impact water quality monitoring as part of the
EM&A programme during the reporting period from 12 to 18
January 2014.
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 construction 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, monitoring locations, Action and Limit Levels, and Event
Action Plan.
Section
4 : Monitoring
Results
Summarises the water quality
monitoring results obtained in the reporting period.
Section
5 : Environmental
Non-conformance
Summarises any monitoring exceedance, environmental complaints and
environmental summons within the reporting period.
Section
6 : Future
Key Issues
Summarises the
monitoring schedule for the next reporting period.
Section
7 : Conclusions
Presents the key findings
of the impact monitoring results.
2
Project Information
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
and was responsible for securing the approval to land the ASE cable in Tseung
Kwan O, Hong Kong SAR (HKSAR). The
landing site is at a Beach Manhole (BMH) and ultimately the cable connects with
a Data Centre in Tseung Kwan O (TKO) Industrial Estate which was completed in
2012. It should be noted that
Tseung Kwan O is currently the landing site for a number of submarine
cables. 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 the cable 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) 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 (the “Project”) in accordance with Updated EM&A
Manual.
Baseline water quality update
monitoring was conducted prior to the re-installation works and results
summarise in the ‘Baseline Water Quality
Monitoring Update Report (Zone A)’of December
2013.
Impact monitoring started on 12
January 2014, when the cable installation works commenced in Zone A. During the reporting period, the impact
monitoring was conducted on a daily basis as the cable installation works proceeded in Zone A.
This Report therefore presents the results and findings from the first
week impact monitoring, conducted from 12 to 18 January 2014 inclusive, at the
monitoring stations in Zone A.
During
the reporting period from 12
to 18 January 2014, the Project submarine cable installation
works all took place within Zone A and included divers locating the ASE cable,
de-burial and burial of the cable involving some water jetting works, cable
recovery and new cable landing.
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 stage
|
Submitted on 18 September 2012
|
|
Updated EM&A
Manual
|
-
|
Throughout the construction stage
|
Submitted on 5 December 2013
|
|
Baseline Water Quality Monitoring
Update Report (Zone A)
|
-
|
Throughout the construction period
for Zone A
|
Submitted on 5 December 2013
|
3
Impact
Water Quality Monitoring Requirements
In accordance with the Updated EM&A Manual,
water quality monitoring samples were collected at the eleven (11) stations
situated around the cable installation works in
Zone A, as soon as the Project marine
installation works started. 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 impact water quality monitoring
was conducted in accordance with the requirements stated in the Updated EM&A Manual. Monitoring
parameters are presented 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.
3.3.1
Monitoring Equipment
Table
3.2 summaries the
equipment used for the impact water quality monitoring.
Table
3.2 Equipment
Used during Impact 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 FP111
|
|
Turbidity Meter
|
HACH Model 2100Q Turbid Meter
|
3.3.2
Monitoring Methodology
Timing & Frequency
In-situ data and
SS data were collected during Project marine installation works from 7:00 to 23:00 on a
daily basis. The impact monitoring
schedule for the reporting period is presented in Annex A.
Impact monitoring commenced when Project marine
installation works started in Zone A.
(The daily sampling works will cease once no Project marine installation
works are being undertaken within Zone A)
Due
to the weather conditions and travelling time between stations, in-situ measurement and SS sampling were
taken at the impact monitoring stations with approximately four-hour intervals
in Zone A. The monitoring frequency
and parameters for impact monitoring are summarised in Table 3.3.
Table 3.3 Monitoring
Frequency and Parameters for Impact Monitoring in Zone A
|
Zone
|
Station
Type
|
Monitoring
Station
|
Monitoring
Frequency
|
Monitoring
Parameter
|
|
A
|
Control
|
C1
|
Daily
at a 4-hour interval while cable installation works are being undertaken in
Zone A
|
Temperature,
Turbidity, Salinity, DO and SS
|
|
Gradient
|
G1, G2, G3
|
|
Impact
|
E7, E8, E9, F1, S1, S2, S3,
|
For in-situ measurements, duplicate readings were made at each water
depth at each station. Duplicate
water samples were also collected at each water depth at each station for the laboratory analysis.
Depths
Measurements/ water samples
were taken at each sampling station, at three depths, namely, 1 m below water
surface, mid-depth and 1 m above sea bed, except where the water depth was less
than 6 m, when the mid-depth sample may have been omitted. For stations that are less than 3 m in
depth, only the mid-depth sample was taken.
Sampling/ Testing Protocols
All in-situ
monitoring instruments were checked, calibrated and certified by a laboratory
accredited under HOKLAS or any other international accreditation scheme before
use, and subsequently re-calibrated at monthly intervals throughout all stages
of the water quality monitoring (Annex
B). 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.
Laboratory 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 C)
3.3.3
Action and Limit Levels
The
Action and Limit levels for Zones A, which were established based on the
results of Baseline Update Monitoring (Zone
A), are presented in Table 3.4.
Table 3.4 Action
and Limit Levels of Water Quality for Zone A
|
Parameter
|
Action
Level
|
Limit
Level
|
|
SS in mgL-1
(Depth-averaged) (a) (c)
|
95%-ile
of baseline data
(7.01
mg L-1), or
|
99%-ile
of baseline data
(7.15
mg L-1) , and
|
|
20%
exceedance of value at any impact station compared with corresponding data
from control station
|
30%
exceedance of value at any impact station compared with corresponding data
from control station
|
|
DO in mgL-1 (b)
|
Surface and Middle(d)
5%-ile
of baseline data for surface and middle layer
(5.91
mg L-1)
|
Surface and Middle(d)
5mg/L
or 1%-ile of baseline for surface and middle layer
(5.85
mg L-1)
|
|
Bottom
5%-ile of baseline data
for bottom layers
(5.72 mg L-1)
|
Bottom
2mg/L or 1%-ile of
baseline data for bottom layer
(5.62 mg L-1)
|
|
Turbidity in NTU (Depth-averaged)
(a) (c)
|
95%-ile
of baseline data
(5.09
NTU), or
|
99%-ile
of baseline data
(5.25
NTU), and
|
|
20%
exceedance of value at any impact station compared with corresponding data
from control station
|
30%
exceedance of value at any impact station compared with corresponding data
from control station
|
|
Notes:
a.
“Depth-averaged”
is calculated by taking the arithmetic means of reading of all sampled
depths.
b.
For
DO, non-compliance of the water quality limits occurs when the monitoring
result is lower than the limits.
c.
For
SS and turbidity, non-compliance of the water quality limits occurs when
monitoring result is higher than the limits.
d.
The
Action and Limit Level for DO for surface and middle layer were calculated
from the combined pool of baseline surface layer data and baseline middle
layer data.
|
3.3.4
Event and Action Plan
The
Event and Action Plan for water quality monitoring which was stipulated in Updated EM&A Manual is presented in Table 3.5.
Table 3.5 Event
Action Plan for Water Quality
Event
|
Contractor
|
|
Action
Level Exceedance
|
Step 1
- repeat sampling event.
Step
2 – Inform EPD and AFCD and confirm
notification of the non-compliance in writing;
Step
3 - discuss with cable installation
contractor the most appropriate method of reducing suspended solids during
cable installation (e.g. reduce cable laying speed/volume of water used
during installation.
Step
4 - repeat measurements after
implementation of mitigation for confirmation of compliance.
Step
5 - if non-compliance continues,
increase measures in Step 3 and repeat measurements in Step 3. If non-compliance occurs a third time,
suspend cable laying operations.
|
|
Limit Level Exceedance
|
Undertake Steps 1-4 immediately, if further non-compliance continues at the
Limit Level, suspend cable laying operations until an effective solution is
identified.
|
4
Impact
Monitoring Results
A total of seven monitoring events were scheduled in the reporting period
from 12 to 18 January 2014 (Annex
A).
Continuous water sampling was taken at the impact monitoring stations in
Zone A at approximately 4-hour intervals (subject to the weather conditions and
travelling time between stations) on a daily basis, so collections were made at
least four (4) times per day.
Monitoring events at all designated monitoring stations within Zone A were performed on schedule. No major activities influencing the
water quality were identified during the reporting period.
The
results of the impact monitoring and their graphical presentations were
included in Annex D.
No exceedances of Action and Limit Levels were recorded. The monitoring results of Turbidity, SS
and DO are discussed together as follows.
The
levels of depth-averaged Turbidity showed variation throughout the first week
impact monitoring (Figure D1 of Annex D). However, no sharp increase in Turbidity
levels was detected on each monitoring day. The differences of Turbidity levels
among the stations were recorded to stay within a limited range of 1 NTU.
Levels
of depth-averaged SS measured during the first week impact monitoring showed trend of
increasing with time (Figure D1 of Annex D). On 12 January 2014, observable
differences among the stations were recorded whilst no exceedances of Action
and Limit Levels were observed. In
general, SS levels were recorded similar among the stations during the first
week impact monitoring except on 12 January 2014.
The
overall levels of DO at all the water depth (surface, mid-depth and bottom)
during the first week impact monitoring were of similar magnitude at all the
stations (Figure D2-3 of Annex D). Minor fluctuations of DO levels at all
water depths were also detected during the reporting period.
In
general, the water quality of Zone A was stable throughout each sampling
day. The overall Turbidity, SS and
DO levels at the impact station were of similar magnitude to the measurement at
the control stations which were located far from the area of cable installation
works and wouldn’t be affected by the repair works. Given this information, the changes of
the measurement in the impact monitoring are considered to be caused by natural
background variation rather than the cable installation works of the
Project.
No
exceedances of the Action and Limit Levels were recorded during the reporting
period.
5.2
Summary
of Environmental Non-compliance
No
non-compliance events were recorded during the reporting period.
No
complaints were received during the reporting period.
No
summons or prosecution on environmental matters were received during the reporting
period.
6
Future
Key Issues
In the week
from 19 to 25 January 2014, the cable installation works in Zone A will include:
-
Making and completing cable joint (no water jetting
work);
-
Laying
down cable joint on seabed (no water jetting work);
-
Diver
inspections (no water jetting work); and
-
Cable
burial works (water jetting work).
Impact water quality monitoring will be
carried out in parallel with the diver jetting for the cable installation works in Zone
A for the week from 19 to 25 January 2014.
7
Conclusions
This
First Weekly Impact Monitoring Report presents the results and findings of
impact water quality monitoring undertaken in Zone A during the period from 12
to 18 January 2014 in
accordance with the Updated EM&A Manual and the requirements
under Environmental Permit (EP - 433/2011)
for the Project.
No
exceedances of Action and Limit Levels were recorded during the impact water quality
monitoring period. No
complaints or summons/prosecutions were received either during the reporting
period.
Water
quality in Zone A was generally stable throughout the reporting period. Similar magnitudes of Turbidity,
SS and DO levels were generally recorded among the stations. Levels of Turbidity, SS and DO levels
showed fluctuation over time during the reporting period.
In
general, the overall water quality at the impact stations was
found to be similar to that at the control stations. After
analysis and comparison between the impact stations and control stations,
overall variations at all sampling stations are considered to have been driven
by natural fluctuations.
It
is concluded that no deterioration of water quality was observed during the
reporting period and hence the effect of the Project cable installation works
on water quality at the Project site was considered to be negligible.
_files/image002.jpg)
_files/image004.jpg)
_files/image006.jpg)