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 the submitted Acoustic Decoupling Measures Plan.
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 (26th June 2014). 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.