4.1
The monitoring results for 1-hour TSP and 24-hour TSP are summarized in Table 4.1 and 4.2 respectively. Graphical presentations of 1-hour and 24-hour TSP monitoring results
are shown in Appendices B and C respectively.
Table 4.1 Summary Table of 1-hour TSP Monitoring
Results during the Reporting Period
|
Month |
Monitoring Station |
Concentration (µg/m3) |
Action
Level, µg/m3 |
Limit
Level, µg/m3 |
|
|
Average |
Range |
||||
|
March 2015 |
AMS1 |
112 |
43 – 179 |
381 |
500 |
|
AMS4 |
114 |
42 – 270 |
352 |
||
|
April 2015 |
AMS1 |
68 |
15 – 168 |
381 |
|
|
AMS4 |
89 |
14 – 177 |
352 |
||
|
May 2015 |
AMS1 |
38 |
19 – 72 |
381 |
|
|
AMS4 |
37 |
15 – 90 |
352 |
||
Table 4.2 Summary
Table of 24-hour TSP Monitoring Results during the Reporting Period
|
Month |
Monitoring Station |
Concentration (µg/m3) |
Action
Level, µg/m3 |
Limit
Level, µg/m3 |
|
|
Average |
Range |
||||
|
March 2015 |
AMS1 |
53 |
28 – 100 |
170 |
260 |
|
AMS4 |
64 |
35 – 105 |
171 |
||
|
April 2015 |
AMS1 |
53 |
27 – 92 |
170 |
|
|
AMS4 |
48 |
27 – 73 |
171 |
||
|
May 2015 |
AMS1 |
37 |
15 – 52 |
170 |
|
|
AMS4 |
29 |
9 – 42 |
171 |
||
4.2
According to our field observations, the major dust source identified at
the designated air quality monitoring stations in the reporting period are as
follows:
Table
4.3 Observation at Dust
Monitoring Stations
|
Monitoring Station |
Major Dust Source |
|
AMS1 |
Exhaust from marine traffic |
|
AMS4 |
N/A |
4.3
The wind data monitoring results were attached in the Monthly EM&A
Reports
4.4
The noise monitoring results are summarized in Table 4.4. Graphical presentations of noise
monitoring are shown in Appendix D.
Table 4.4 Summary
Table of Noise
Monitoring Results during the Reporting Period
|
Month |
Monitoring Station |
Noise Level, Leq (30min) dB(A) |
Limit
Level |
|
|
Average |
Range |
|||
|
March 2015 |
NMS1 |
68 |
65 - 72 |
75 dB(A) |
|
NMS4 |
61 |
53 – 66 |
||
|
April 2015 |
NMS1 |
71 |
68 - 73 |
|
|
NMS4 |
67 |
63 – 69 |
||
|
May 2015 |
NMS1 |
69 |
67 - 72 |
|
|
NMS4 |
63 |
57 – 66 |
||
Remark: +3dB(A) Façade correction included
4.5
According to our field observations, the major noise source identified
at the designated noise monitoring stations in the reporting period are as
follows:
Table 4.5 Observation
at Noise
Monitoring Stations
|
Monitoring Station |
Major Noise Source |
|
NMS1 |
Air
traffic & marine traffic noise |
|
NMS4 |
Air
traffic & marine traffic noise |
4.6
The graphical presentation of water quality at the monitoring stations
is shown in Appendix E.
4.7
Water quality impact sources during the water quality monitoring were
the construction activities of the Contract, nearby construction activities by
other parties and nearby operating vessels by other parties.
Summary
of survey effort and dolphin sightings
4.8
During the period of March
to May 2015, six sets of systematic line-transect vessel surveys were conducted to
cover all transect lines in WL survey area twice per month.
4.9
From these surveys, a total of 196.44 km of survey effort was collected, with 86.9% of the total survey effort being conducted
under favourable weather conditions (i.e. Beaufort Sea State 3 or below with
good visibility). The total survey effort conducted on primary
lines was 130.31
km, while the effort on secondary lines was 66.13km. Survey effort
conducted on primary and secondary lines were both considered as on-effort
survey data. Summary table of the
survey effort is shown in Appendix I of Appendix F.
4.10
During the six sets of monitoring surveys in March
to May 2015, a total of 29
groups of 97 Chinese White
Dolphins were sighted. All except three sightings were made during on-effort
search. Fourteen on-effort sightings were made on primary lines, while the other on-effort sightings were made on secondary
lines. Summary table of the
dolphin sightings is shown in Appendix
II of Appendix F.
Distribution
4.11
Distribution of dolphin sightings made during
monitoring surveys in March to May 2015 is
shown in Figure 1 of Appendix F. The
dolphin groups were evenly distributed throughout the WL survey area, with higher
concentrations of sightings to the north of Tai O Peninsula and near Kai Kung
Shan (Figure
1 of Appendix
F). However, it appeared that they occurred
less frequently at the southern end of the survey area.
4.12
Sighting distribution of dolphins in the
present quarter was similar to the one during the baseline period, with some
subtle differences. There appeared
to be fewer dolphins sighted in the offshore waters of West Lantau survey area
(especially in the northern portion of the survey area) during the present
monitoring quarter when compared to the dolphin distribution record in the
baseline period.
4.13
Only one of the 29 dolphin groups was sighted
near the HKLR09 alignment in WL survey area during the present quarter (Figure 1 of Appendix F).
Encounter
rate
4.14
During the three-month impact phase
monitoring period (March – May 2015), the encounter rates of Chinese White
Dolphins deduced from the survey effort and on-effort sighting data from the
primary transect lines under favourable conditions (Beaufort 3 or below) from
West Lantau survey area are shown in Table
4.6. The average encounter
rates deduced from the six sets of surveys from present quarter were also compared with the ones deduced from the baseline monitoring
period (September – November 2011) (Table
4.7).
Table 4.6 Dolphin encounter rates (sightings
per 100 km of survey effort) during the impact monitoring period (March – May
2015)
|
Survey Area |
Dolphin Monitoring |
Encounter rate (STG) |
Encounter rate (ANI) |
|
Primary Lines Only |
Primary Lines Only |
||
|
West Lantau |
9.7 |
106.4 |
|
|
Set 2 (March 27th) |
18.7 |
56.1 |
|
|
Set 3 (April 2nd) |
12.2 |
12.2 |
|
|
Set 4 (April 13th) |
5.8 |
5.8 |
|
|
Set 5 (May 7th) |
15.1 |
65.3 |
|
|
Set 6 (May 15th) |
13.1 |
26.1 |
Table 4.7 Comparison of average dolphin
encounter rates from impact monitoring period (March – May 2015) and baseline
monitoring period (September-November 2011)
|
|
(no. of on-effort dolphin sightings per 100 km of survey effort) |
Encounter rate (ANI) (no. of dolphins from all
on-effort sightings per 100 km of survey effort) |
||
|
March - May 2015 |
September- November 2011 |
March - May 2015 |
September- November 2011 |
|
|
West Lantau |
12.42
± 4.42 |
16.43 ± 7.70 |
45.32
± 38.14 |
60.50 ± 38.47 |
4.15
The encounter rates were also calculated for
the present quarter using both primary and secondary survey effort. The encounter rates of sightings (STG) and dolphins
(ANI) in WL were 15.2 sightings and 53.3 dolphins per 100 km of survey effort
respectively during the present quarter.
4.16
A one-way ANOVA was conducted to examine
whether there were any significant differences in the average encounter rates
between the baseline and impact monitoring periods. For the comparison between the baseline
period and the present quarter (i.e. ninth quarter of the impact phase), the p-value
for the differences in average dolphin encounter rates of STG and ANI were 0.294 and 0.954
respectively.
Therefore, no significant difference in dolphin encounter rate was
detected between the baseline period and the present quarter.
4.17
Another comparison was made between the
baseline period and the cumulative quarters in the impact phase (i.e. first nine quarters of the impact phase), and the p-value for the differences
in average dolphin encounter rates of STG and ANI were 0.508 and 0.999 respectively. As a result, no
significant difference was found in the dolphin encounter rates between the
baseline period and the cumulative quarters in the impact phase.
Group
size
4.18
Group size of Chinese White
Dolphins ranged from 1-20 individuals per group in WL survey area
between March and
May 2015.
The average dolphin group sizes from these three-month period was
compared with the one deduced from the baseline period in September to November
2011, as shown in Table 4.8. The average dolphin group size in the WL
region during the present quarter was slightly lower
than the one recorded in the three-month baseline period (Table 4.8). The majority of the dolphin groups (79.3%) were
composed of 1-3 dolphins, but there were also six groups with more than 5
animals per group, and one very large group with 20 animals.
Table 4.8 Comparison of average dolphin
group sizes from impact monitoring period (March – May 2015) and baseline
monitoring period (September-November 2011)
|
|
Average Dolphin Group
Size |
|
|
March – May
2015 |
September to November 2014 |
|
|
West Lantau |
3.34 ± 3.81 (n = 29) |
3.63 ± 2.97 (n = 46) |
4.19
Distribution of dolphins with the
larger groups during March to May 2015 is shown Figure 4 of Appendix F. These groups were scattered from the
bridge alignment to Fan Lau waters, with slightly higher concentration near Kai
Kung Shan. This was slightly
different from the baseline period, when the larger dolphin groups mostly
occurred to the northwest of Tai O Peninsula (near the bridge alignment) as
well as near Kai Kung Shan and Peaked Hill (Figure 4 of Appendix F).
Habitat
use
4.20
From March to May 2015, the
most heavily utilized habitats by the dolphins were mainly found near Tai O
Peninsula, Kai Kung Shan and Fan Lau (Figures
5a and 5b of Appendix F). However, it should be cautioned that the
amount of survey effort collected in each grid during the three-month period was fairly low
(6 units of survey effort for most grids), and therefore the habitat use
pattern derived from the three-month dataset should be treated with
caution. A more complete picture of
dolphin habitat use pattern will be presented when more survey effort for each
grid will be collected throughout the impact phase monitoring programme.
4.21
When compared with the habitat
use pattern recorded during the baseline period, it appears that the overall
dolphin densities were lower in West Lantau waters, especially the waters
adjacent to Tai O Peninsula, around Peaked Hill and near Fan Lau during the
present quarter (Figure 6 of Appendix F).
Mother-calf
pairs
4.22
During the three-month impact phase monitoring period, only two unspotted juveniles (UJ) were sighted in WL
survey area. The young calves
comprised 2.0% of all animals sighted, which was less than
one-third of the
percentage recorded during the baseline monitoring period (6.6%).
4.23
The infrequent occurrences of
the two mother-calf pairs were located near Fan Lau and Tai O Peninsula (Figure 7 of Appendix F). This was in stark contrast to the
baseline period when calf occurrence was frequent and more concentrated near
Tai O Peninsula at the northern portion of WL waters (Figure 7 of Appendix F).
Activities
and associations with fishing boats
4.24
During the three-month impact
monitoring period, four dolphin sightings were associated with feeding activities between the HKLR09 bridge alignment and Peaked Hill (Figure 8 of Appendix F), comprising 13.8% of
the total number of dolphin sightings.
This percentage was very similar to the percentage recorded
during the baseline period.
4.25
On the other hand, only one of
the 29 sightings was associated with socializing activity near the HKLR09
bridge alignment (Figure 8 of Appendix F),
while no dolphin group was engaged in traveling or milling/resting activity
during the present quarter.
4.26
Notably, distribution of the
feeding and socializing activities during the present impact phase monitoring
period was somewhat different from the one during the baseline period, with the
main concentration of these activities occurred between Tai O and Peaked Hill
during the baseline period but no particular concentration of these activities
during the impact phase period (Figure 8 of Appendix F).
4.27
During the three-month monitoring period, one of the dolphin groups was associated with an operating
hang-trawler near the HKLR09 bridge alignment.
Summary
of photo-identification works
4.28
From March to May 2015, over
2,000 digital photographs of Chinese White Dolphins were taken during the
impact phase monitoring surveys for the photo-identification work.
4.29
In total, 33 individuals
sighted 45 times altogether were identified (see summary table in Appendix III of Appendix F and photographs of identified
individuals in Appendix IV of Appendix F. Almost all identified individuals were
sighted only once or twice during the three-month period, but one individual
(WL72) were sighted three times.
4.30
Notably, two of these 33
individuals (i.e. NL123, NL285) were also sighted in North Lantau waters during
the HKLR03 monitoring surveys in the same three-month period, showing some
movements across the HKLR09 bridge alignment. Moreover, as in previous quarters, some
individuals that were consistently sighted in North Lantau waters in the past
were identified in West Lantau waters (e.g. NL123, NL188, NL226, NL286). It is
possible that some of these identified dolphins have shifted their range use
into West Lantau.
4.31
During the three-month period,
four recognizable females, NL123, NL188, WL44 and WL171, were accompanied with
their calves during their re-sightings.
Individual
range use
4.32
Ranging patterns of the 33 individuals
identified during the three-month study period were determined by fixed kernel
method, and are shown in Appendix V of Appendix F.
4.33
For those that primarily used
West Lantau waters as their home ranges, most of their re-sightings were made
at a distance away from the HKLR09 alignment where they were frequently
re-sighted in the past. It is
possible that their range use in West Lantau waters have been somewhat affected
by the HKLR09 construction activities with some moderate shift in range use.
Conclusion
4.34
During this quarter of dolphin
monitoring, no adverse impact from the activities of the HKLR09 construction
project on Chinese White Dolphins was noticeable from general observations.
4.35
Nevertheless, the dolphin usage
in WL region should be continuously monitored, to further examine whether it
has been significantly affected by the on-going construction activities in
relation to the HZMB works.
4.36
Additional land-based dolphin behavior and movement monitoring were
conducted in the reporting period. The progress of the monitoring is summarized
in the Table 4.9.
Table 4.9 Progress
Record of Additional Land-based Dolphin Behaviour and Movement Monitoring (March to May 2015)
|
Date |
Time |
Weather |
Number of Staff |
Number of Dolphin Sighting |
|
|
Beaufort |
Visibility |
||||
|
09/03/2015 |
09:16 - 14:42 |
1 |
3.5-4 |
3 |
1 |
|
13/03/2015 |
09:04 - 14:35 |
2 |
1.5-2 |
3 |
1 |
|
14/04/2015 |
09:21
- 14:49 |
2 |
1 |
3 |
1 |
|
20/04/2015 |
09:14
- 14:32 |
2 |
3.5 |
3 |
0 |
|
11/05/2015 |
09:16
- 14:36 |
2 |
1.5 |
3 |
0 |
|
19/05/2015 |
09:04
- 14:05 |
2-3 |
2 |
3 |
0 |
4.37
Detailed monitoring methodology and results will be provided in a
separate report after the completion of full set of additional land-based
dolphin behavior and movement monitoring.
4.38
The Contractor was advised to minimize the wastes generated through the
recycling or reusing. All mitigation measures stipulated in approved waste management
plan shall be fully implemented.
4.39
The amount of wastes generated by the activities of the Contract during
the reporting month is shown in Appendix
J.