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 < 60%
of baseline & ANI <60% of baseline |
Limit Level |
STG < 45%
of baseline & ANI <45% of baseline |
Derived Value of Action Level (AL) and Limit Level (LL):
|
West Lantau |
Action Level |
STG < 9.8
& ANI <36.3 |
Limit Level |
STG < 7.4
& ANI <27.2 |
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 EP Condition 3.7 and EM&A Manual, Section 10.2.18.
3.9
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 (17th March
2015). 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.