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 2014 |
AMS1 |
46 |
17 - 79 |
381 |
500 |
AMS4 |
38 |
19 - 82 |
352 |
||
April 2014 |
AMS1 |
46 |
18 - 114 |
381 |
|
AMS4 |
39 |
18 - 66 |
352 |
||
May 2014 |
AMS1 |
32 |
14 - 89 |
381 |
|
AMS4 |
27 |
14 - 104 |
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 2014 |
AMS1 |
71 |
30 - 118 |
170 |
260 |
AMS4 |
68 |
29 - 103 |
171 |
||
April 2014 |
AMS1 |
39 |
18 - 62 |
170 |
|
AMS4 |
44 |
21 - 60 |
171 |
||
May 2014 |
AMS1 |
22 |
13 - 35 |
170 |
|
AMS4 |
29 |
10 - 65 |
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 |
1) Exhaust
from marine traffic 2) Other
construction site nearby |
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 2014 |
NMS1 |
72 |
69 – 74 |
75 dB(A) |
NMS4 |
63 |
61 – 65 |
||
April 2014 |
NMS1 |
72 |
71 – 72 |
|
NMS4 |
61 |
59 – 62 |
||
May 2014 |
NMS1 |
71 |
65 – 74 |
|
NMS4 |
61 |
59 – 63 |
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 near by operating vessels by other
parties.
Summary of survey effort and dolphin
sightings
4.8
During the period of March
to May 2014, 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 192.12
km of survey effort was collected, with 82.2% 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 127.56 km, while the effort on secondary lines was 64.56
km. 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 2014,
a total of 25 groups of 120
Chinese White Dolphins were sighted.
All sightings were made during on-effort search. Seventeen
on-effort sightings were made on primary lines, while another eight
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 2014
is shown in Figure 1 of Appendix F. The dolphin groups were evenly distributed
throughout the WL survey area, with higher concentrations between Kai Kung Shan
and Fan Lau. The only areas where dolphins were rarely sighted included the
northern end of the survey area. (i.e. near and to the north of HKLR09
alignment)
4.12
Sighting distribution of dolphins in the
present quarter was quite different from the one during the baseline period,
with fewer dolphins being sighted in the northern portion of the survey area
between the bridge alignment and Kai Kung Shan in the present impact monitoring
quarter
4.13
Notably, only one sighting was made along the
HKLR09 alignment in WL survey area during the present quarter (Figure 1 of Appendix F). There appeared to be a general shift in
dolphin distribution further south of the WL survey area in the present
quarter, and they rarely occurred at the juncture between NWL and WL survey
areas. (Figure 2 of Appendix
F)
Encounter rate
4.14
During the three-month impact phase
monitoring period, 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 March to May 2014
were also compared with the ones deduced from the baseline monitoring period
(September – November 2011) (Table 4.7).
4.15
In WL survey area, the average dolphin
encounter rates in the present three-month study period was slightly lower in ER (STG) (STG)
but slightly higher in ER (ANI) than the ones recorded in the 3-month baseline
period respectively, indicating the dolphin usage during this impact phase
monitoring period in this survey area were more or less than same when compared to
the baseline phase.
Table 4.6 Dolphin encounter rates (sightings per 100 km of
survey effort) during the impact monitoring period (March – May 2014)
Survey Area |
Dolphin Monitoring |
Encounter rate (STG) |
Encounter rate (ANI) |
Primary Lines Only |
Primary Lines Only |
||
West Lantau |
(March 12, 2014) |
14.8 |
84.0 |
Set 2
(March 26, 2014) |
28.4 |
132.8 |
|
Set 3 |
23.4 |
58.6 |
|
Set 4 |
0.0 |
0.0 |
|
Set 5 |
9.2 |
32.3 |
|
Set 6 |
10.5 |
83.8 |
Table 4.7 Comparison of average dolphin encounter rates from
impact monitoring period (March
– May 2014) 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 2014 |
September- November 2011 |
March-May 2014 |
September- November 2011 |
|
West Lantau |
14.40 ± 10.28 |
16.43 ± 7.70 |
65.23 ± 46.13 |
60.50 ± 38.47 |
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 (fifth quarter of the impact phase), the p-value for the differences in average dolphin encounter rates of STG and ANI were 0.706 and 0.873 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 four quarters of the impact phase), and the p-value for the differences in average dolphin encounter rates of STG and ANI were 0.784 and 0.969 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.
4.18 To facilitate the comparison with the AFCD long-term monitoring results, the encounter rates were also calculated for the present quarter (March to May 2014) using both primary and secondary survey effort. The encounter rates of sightings (STG) and dolphins (ANI) in WL were 15.2 sightings and 70.9 dolphins per 100 km of survey effort respectively.
Group size
4.19 Group size of Chinese White Dolphins ranged from 1-13 individuals per group in WL survey area between March to May 2014. The average dolphin group sizes from these three months were 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 March to May 2014 was higher than the ones recorded in the 3-month baseline period (Table 4.8). About half of the dolphin groups were composed of 1-2 dolphins, but there were also 11 groups with more than 5 animals per group, and four groups with 10 animals or more per group. One of the larger groups was associated with an operating purse-seiner.
Table 4.8 Comparison of average dolphin group sizes from
impact monitoring period (March
– May 2014) and baseline monitoring period
(September-November 2011)
|
Average Dolphin Group
Size |
|
March to May
2014 |
September – November 2011 |
|
West Lantau |
4.80 ± 4.08 (n = 25) |
3.63 ± 2.97 (n = 46) |
4.20 Distribution of dolphins with these 11 larger groups during March to May 2014 is shown in Figure 3 of Appendix F. These groups were evenly distributed between Tai O Peninsula and Fan Lau, but were generally far away from the HKLR09 alignment.
Habitat use
4.21 From March to May 2014, the most heavily utilized habitats by the dolphins mainly concentrated near Tai O Peninsula, Kai Kung Shan, Peaked Hill and Fan Lau (Figures 4a and 4b of Appendix F). However, it should be noted 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.
4.22 When compared with the habitat use pattern recorded during the baseline period, it appears that dolphin densities were lower between the HKLR09 alignment and Tai O Peninsula during the present impact phase monitoring period (Figure 5 of Appendix F).
Mother-calf pairs
4.23 During the three-month impact phase monitoring period, two unspotted calves and seven unspotted juveniles (UJ) were sighted in WL survey area. These young calves comprised 7.5% of all animals sighted, which was slightly higher than the percentage recorded during the baseline monitoring period (6.6%).
4.24 The occurrence of these young calves were scattered between the bridge alignment and Peaked Hill, which was in stark contrast to the baseline period when calf occurrence was more frequent near Tai O Peninsula (Figure 6 of Appendix F).
Activities and associations
with fishing boats
4.25 A total of two dolphin sightings were associated with feeding activities near Fan Lau (Figure 7 of Appendix F), comprising of 8% of the total number of dolphin sightings. This percentage was much lower than the percentage recorded during the baseline period (13.0%). Only one of the 25 sightings was associated with socializing activity near the artificial island in Chinese waters (Figure 7 of Appendix F).
4.26 Although traveling activities were rarely observed during the baseline period and previous impact monitoring periods, three sightings of this type of activities were recorded during the present 3-mont period, which were located near Peaked Hill and Kai Kung Shan (Figure 7 of Appendix F). One sighting of dolphins engaged in milling/resting was also recorded near Peaked Hill (Figure 7 of Appendix F).
4.27 During the three-month period, only
one dolphin group was associated
with an operating purse-seiner.
Summary of
photo-identification works
4.28 From March to May 2014, over 2,500 digital photographs of Chinese White Dolphins were taken during the impact phase monitoring surveys for the photo-identification work.
4.29 In total, 55 individuals sighted 74 times altogether were identified (see summary table in Appendix III of Appendix F and photographs of identified individuals in Appendix IV of Appendix F. The majority of identified individuals were sighted only once or twice during the three-month period, but three individuals (CH108, WL62 and WL86) were sighted thrice.
4.30 During the three-month period, ten recognizable females, including CH105, NL33, NL98, NL264, NL304, WL28, WL86, WL98, WL118 and WL224, were sighted to be accompanied with their calf during her re-sighting. Notably, NL33, NL98 and NL264 spent most of their time in North Lantau waters in the past.
Individual range use
4.31 Ranging patterns of the 55 individuals identified during the three-month study period were determined by fixed kernel method, and are shown in Appendix V of Appendix F.
4.32 Among these 55 individuals, eight of them (NL33, NL98, NL182, NL264, NL288, NL295, WL04 and WL05) occurred primarily in North Lantau and ventured into West Lantau during the three-month period, while five other individuals (NL156, NL304, WL15, WL46 and WL179) split their time between North and West Lantau waters. The other 42 individuals centered their range use in West Lantau waters. (Appendix V of Appendix F)
Conclusion
4.33 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.
4.34 Nevertheless, dolphin usage in WL region should be continuously monitored, to further examine whether it has been affected by the on-going construction activities in relation to the HZMB works.
4.35 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 2014)
Date |
Time |
Weather |
Number
of Staff |
Number
of Dolphin Sighting |
|
Beaufort |
Visibility |
||||
14/03/2014 |
09:30 – 15:04 |
2 – 3 |
2.5 |
3 |
2 |
19/03/2014 |
09:16 – 14:30 |
1 |
2.5 - 3 |
3 |
4 |
16/4/2014 |
09:05 - 14:49 |
2-3 |
2.5-3 |
3 |
2 |
25/4/2014 |
09:08 - 14:47 |
2-4 |
2 |
3 |
0 |
19/5/2014 |
09:43 - 15:07 |
2-4 |
1 |
3 |
2 |
27/5/2014 |
09:04 - 14:32 |
1-3 |
1.5-2.5 |
3 |
1 |
4.36
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.
4.37
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.
4.38
The
amount of wastes generated by the activities of the Contract during the
reporting month is shown in Appendix J.