3.1
The
EM&A Manual designates locations for the ET to monitor environmental
impacts in terms of air quality, noise, underwater noise, water quality and
dolphin to the Contract. The monitoring locations are depicted in Figures 3 to 6. The details of
monitoring requirements are presented in Table
3.1.
Table 3.1 Summary of Impact EM&A Requirements
|
Type of Monitoring |
Parameter |
Frequency |
Location |
Remarks |
|
Air
Quality |
1-hr
TSP |
Three
times / 6 days |
AMS1
– Sha Lo Wan AMS4
– San Tau |
While
the highest dust
impact was expected |
|
24-hr
TSP |
Once
/ 6 days |
-- |
||
|
Noise |
L10(30
min.) dB(A) L90(30
min.) dB(A) Leq(30 min.) dB(A) (as six
consecutive Leq, 5min
readings) |
Once per week |
NMS1
– Sha Lo Wan NMS4
– San Tau |
Daytime
on normal weekdays
(0700-1900
hrs) |
|
Water
Quality |
·
Temperature(°C) ·
pH(pH unit) ·
turbidity
(NTU) ·
water depth
(m) ·
salinity (ppt) ·
dissolved
oxygen (DO) (mg/L and % of saturation) ·
suspended
solids (SS) (mg/L) |
Impact
monitoring: 3 days per week, at mid-flood and mid-ebb tides (within ± 1.75
hour of the predicted time) during the construction period of the Contract |
IS1,
IS2, IS3 IS4,
CS1, CS2, SR1, SR2, SR3, SR6, ST1, ST2, ST3, SRA |
·
3 water depths: 1m below sea surface, mid-depth and 1m above sea bed.
·
If the water
depth is less than 3m, mid-depth sampling only. ·
If water depth
less than 6m, mid-depth may be omitted. |
|
Dolphin |
Line-transect Methods |
Twice
per month |
West Lantau |
-- |
3.2
The
wind speed and wind direction were recorded by the installed Wind Anemometer
set at AMS4. The location is shown in Figure
3.
3.3
Monitoring
works/equipments were conducted/calibrated regularly in accordance with the
EM&A Manual. Copies of calibration certificates are attached in the
appendices of the Monthly EM&A Reports.
3.4
The
environmental quality performance limits, i.e. Action and Limit Levels were
derived from the baseline monitoring results (except the Action and Limit
Levels for underwater noise monitoring). Should the measured environmental quality
parameters exceed the Action/Limit Levels, the respective action plans would be
implemented. The Action/Limit
Levels for each environmental parameter are given in Table 3.2a-f.
Table 3.2a Action and Limit Levels for 1-Hour TSP
|
Location |
Action
Level, μg/m3 |
Limit Level, μg/m3 |
|
AMS1 |
381 |
500 |
|
AMS4 |
352 |
Table 3.2b Action and Limit Levels for 24-Hour TSP
|
Location |
Action Level, μg/m3 |
Limit Level, μg/m3 |
|
AMS1 |
170 |
260 |
|
AMS4 |
171 |
Table 3.2c Action and Limit Levels for Construction Noise
|
Time Period |
Action Level |
Limit Level |
|
0700-1900 hrs on normal weekdays |
When one documented complaint is received |
75 dB(A) * |
Noted: If works are to be carried during restricted hours, the
conditions stipulated in the construction noise permit issued by the Noise
Control Authority have to be followed.
(*) reduce
to 70 dB(A) for schools and 65 dB(A) during school
examination periods.
Table 3.2d Action and Limit Levels for Water Quality
|
Parameter
(unit) |
Water Depth |
Action Level |
Limit Level |
|
Dissolved Oxygen (mg/L)
(surface, middle, bottom) |
Surface and Middle |
5.0 |
4.2 except 5 for FCZ |
|
Bottom |
4.7 |
3.6 |
|
|
Turbidity (NTU) |
Depth average |
27.5 and 120% of upstream control station’s
turbidity at the same tide of the same day |
47.0 and 130% of turbidity at the upstream control
station at the same tide of same day |
|
Suspended Solids (mg/L) |
Depth average
|
23.5
and 120% of upstream
control station’s SS at the same tide of the same day |
34.4 and 130% of SS at the upstream control station at
the same tide of same day and
10mg/L for WSD Seawater Intakes |
Note:
(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) All the
figures given in the table are used for reference only and the EPD may amend
the figures whenever it is considered as necessary.
(5) The 1%-ile of baseline data for dissolved oxygen (surface and
middle) and dissolved oxygen (bottom) are 4.2mg/L and 3.6mg/L respectively.
Table 3.2e Action and Limit Levels for Dolphin Line Transect Monitoring
|
|
West Lantau |
|
Action Level |
STG < 9.8 & ANI
<36.3 |
|
Limit Level |
STG < 7.4 & ANI
<27.2 |
Derived Value of Action Level (AL) and Limit Level (LL):
|
|
West Lantau |
|
Action Level |
STG < 60% of baseline &
ANI <60% of baseline |
|
Limit Level |
STG < 45% of baseline &
ANI <45% of baseline |
Remarks:
1. STG means quarterly encounter rate of number of dolphin sightings
2. ANI means quarterly encounter rate of total number of dolphins
3. Baseline value: 16.4 for ER (STG) and 60.5 for ER (ANI)
3.5
Should
non-compliance of the criteria occur, action in accordance with the Action Plan
in Appendix G shall be carried out.
3.6
Relevant
mitigation measures as recommended in the EIA report have been stipulated in
the EM&A Manual for the Contractor to implement. The
implementation status of environmental mitigation measures (EMIS) is given in Appendix H.
3.7
Regular
marine travel route for marine vessels were implemented properly in accordance with
the submitted plan and relevant records were kept properly.
3.8
Acoustic
decoupling measures for the stationary equipment (generators, winch generators
and air compressors) mounted on boards were adopted according to the approved
Acoustic Decoupling Measures Plan.
3.9
Dolphin
exclusion zone was implemented by ET’s trained dolphin observer in accordance
with EP Condition 3.4. In addition, dolphin exclusion zone and dolphin watching
plan according to EM&A Manual, Section 10.2.12 and EP Condition 3.5 was
implemented by DCVJV’s trained dolphin watcher.
3.10
Spill kits
and booms are ready on site for the event of accidental spillage of oil or
other hazardous chemicals from construction activities including vessels
operating for the Contract.
3.11
Site
audits were carried out by ET on weekly basis to monitor the timely
implementation of proper environmental management practices and mitigation
measures in the Contract site. The observations and recommendations made during
the reporting period are summarized in Appendix
I.
3.12
According
to EP condition 4.7 and EM&A Manual, periodic monitoring (every three
months) of construction works shall be conducted to ensure the avoidance of any
impacts on Sha Lo Wan (West) Archaeological Site.
Access to Sha Lo Wan (West) Archaeological site for
works areas and storage of construction equipment is not allowed. One inspection
to the Sha Lo Wan (West) Archaeological Site was
conducted in the reporting period (10th September 2013). No access to Sha Lo
Wan (West) Archaeological site for works areas and storage of construction
equipment was observed. The photographic records of the inspection to the Sha Lo Wan (West) Archaeological Site are shown in the Monthly
EM&A Reports.
3.13
The
amount of wastes generated by the activities of the Contract during the
reporting month is shown in Appendix J.