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 |
||||
|
December 2016 |
AMS1 |
83 |
40 – 172 |
381 |
500 |
|
AMS4 |
43 |
4 – 103 |
352 |
||
|
January 2017 |
AMS1 |
71 |
18 – 115 |
381 |
|
|
AMS4 |
52 |
25 – 95 |
352 |
||
|
February 2017 |
AMS1 |
113 |
24 – 243 |
381 |
|
|
AMS4 |
62 |
21 – 144 |
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 |
||||
|
December 2016 |
AMS1 |
73 |
44 – 95 |
170 |
260 |
|
AMS4 |
69 |
38 – 95 |
171 |
||
|
January 2017 |
AMS1 |
109 |
61 – 164 |
170 |
|
|
AMS4 |
71 |
52 – 89 |
171 |
||
|
February 2017 |
AMS1 |
50 |
13 – 83 |
170 |
|
|
AMS4 |
56 |
46 – 73 |
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 |
|||
|
December 2016 |
NMS1 |
64 |
56 – 68 |
75 dB(A) |
|
NMS4 |
62 |
56 – 67 |
||
|
January 2017 |
NMS1 |
71 |
61 – 73 |
|
|
NMS4 |
64 |
53 – 66 |
||
|
February 2017 |
NMS1 |
64 |
61 – 67 |
|
|
NMS4 |
62 |
61 – 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 nearby operating vessels by other parties.
Summary
of survey effort and dolphin sightings
4.8
During the period of September
to November 2016, 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 193.92 km of survey effort was collected, with 88.6% 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 129.71 km, while the effort on secondary lines was 64.21 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 December 2016 to February 2017, a total of 25 groups of 84 Chinese White Dolphins were sighted. All dolphin
sightings were made during on-effort search. Fifteen on-effort sightings were made on primary lines, while the other nine 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 December 2016 to February 2017 is shown in Figure 1 of Appendix F. The dolphin groups were evenly
distributed in the central portion of the survey area (i.e. between Tai O
Peninsula and Peaked Hill) during the quarterly period (Figure 1 of Appendix F). On the contrary, they rarely occurred in
the northern section of the survey area near HKLR09 alignment, and the southern
section near Fan Lau (Figure 1 of
Appendix F).
4.12
Sighting distribution of dolphins in the present
quarter was quite different from the one during the baseline period in
September to November 2011. When compared
to the baseline period, dolphins occurred much less frequently in the to the
north of Tai O Peninsula, but more frequently in waters between Peaked Hill and
Fan Lau during the present impact phase period (Figure 1 of Appendix
F).
4.13
Only one of the 25 dolphin groups was sighted
near the HKLR09 alignment in WL survey area during the present quarter (Figure 2 of Appendix F).
4.14
Distribution patterns of dolphin sightings in the
past three winter quarters of 2013-16 were also compared with the one in 2016-17.
Dolphins appeared to occur less frequently near Fan Lau but more frequently at
the offshore waters especially to the west of Tai O Peninsula in the winter of
2016-17 when compared to the previous three winter periods (Figure 3 of Appendix F).
Encounter
rate
4.15
During the present three-month impact phase
monitoring period (December 2016 to February 2017), 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 the 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 (December 2016
–February 2017)
|
Survey Area |
Dolphin Monitoring |
Encounter rate (STG) |
Encounter rate (ANI) |
|
Primary Lines Only |
Primary Lines Only |
||
|
West Lantau |
14.9 |
39.6 |
|
|
Set 2 (December 12th) |
0.0 |
0.0 |
|
|
Set 3 (January 3rd) |
13.0 |
19.5 |
|
|
Set 4 (January 9th) |
13.2 |
35.2 |
|
|
Set 5 (February 6th) |
21.8 |
116.4 |
|
|
Set 6 (February 13th) |
18.6 |
69.6 |
Table 4.7 Comparison of average dolphin
encounter rates from impact monitoring period (September to November 2016) 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) |
||
|
December 2016 –February
2017 |
September- November 2011 |
December 2016 –February
2017 |
September- November 2011 |
|
|
West Lantau |
13.58
± 7.47 |
16.43 ± 7.70 |
46.73
± 41.18 |
60.50 ± 38.47 |
4.16
Notably,
the encounter rates of dolphin sightings (ER(STG)) and encounter rates of
dolphins (ER(ANI)) for the present winter quarter of 2016-17 were similar to
the ones in recent past quarters, but were lower than the baseline level and
the first year of impact phase monitoring in 2013 (Table 4 of Appendix F). Such temporal trend should be continuously
monitored, even though the Action or Limit Level still has not been triggered
under the Event and Action Plan for this quarter.
4.17
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. fifteenth
quarter of the impact phase), the p-value for the differences in average
dolphin encounter rates of STG and ANI were 0.529 and 0.563 respectively. Therefore, no significant difference in
dolphin encounter rate was detected between the baseline period and the present
quarter.
4.18
Another
comparison was made between the baseline period and the cumulative quarters in the
impact phase (i.e. first thirteen quarters of the impact phase), and the
p-value for the differences in average dolphin encounter rates of STG and ANI
were 0.688 and 0.822 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
4.19
Group size of Chinese White
Dolphins ranged from 1-12 individuals per group in WL survey area during December
2016 to February 2017. The average
dolphin group size for the three-month period was compared with the one deduced
from the baseline period in September to November 2011, as shown in Table 4.8.
Table 4.8 Comparison of average dolphin
group sizes from impact monitoring period (September – November 2016) and baseline
monitoring period (September-November 2011)
|
|
Average Dolphin Group
Size |
|
|
December 2016 – February 2017 |
September – November 2011 |
|
|
West Lantau |
3.36 ± 2.90 (n = 25) |
3.63 ± 2.97 (n = 46) |
4.20
The average dolphin group size
in the WL region during the present quarter was slightly
higher than the one recorded in the three-month baseline period (Table 4.8). Among the 23 groups, 14 of them were
composed of only 1-4 dolphins, while there were nine groups with five or more
animals per group.
4.21
Distribution of dolphins with the
larger groups during December 2016 to February 2017 is shown in Figure 4 of Appendix F. These groups were scattered in the central
portion of the WL survey area between Tai O Peninsula and Peaked Hill,and one exceptionally large
group of 12 dolphins was sighted near Kai Kung Shan (Figure 4 of Appendix F).
4.22
Distribution of larger dolphin
groups in the present impact phase period was very different from the baseline
period, with the only exception that larger groups were more often found to the
north of Tai O Peninsula during the baseline period (Figure 4 of Appendix F).
Habitat
use
4.23
From December 2016 to February
2017, the most heavily utilized habitats by the dolphins with higher densities
were to the north of Kai Kung Shan, near Peaked Hill 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 (six 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.
4.24
When compared with the habitat
use pattern recorded during the baseline period in September-November 2011, it
appears that the overall dolphin densities were less evenly distributed in the
present impact phase monitoring period, and were much lower in certain areas
such as the waters just to the south of the HKLR09 alignment and near Fan Lau (Figure 6 of Appendix F).
Mother-calf
pairs
4.25
During the three-month impact phase monitoring period, no young calf
was sighted at all among the 25 groups of dolphins.
Activities
and associations with fishing boats
4.26
During the three-month impact
monitoring period, four dolphin groups were engaged in feeding activities to
the southwest of Tai O Peninsula and to the west of Kai Kung Shan (Figure 8 of Appendix F), comprising 16.0%
of the total number of dolphin sightings. This percentage was slightly higher
than the percentage recorded during the baseline period (13.0%).
4.27
On the other hand, no dolphin
group was engaged in socializing, traveling or resting activity during the
present quarter (Figure 8 of Appendix F).
4.28
Distribution of different
activities during the present impact phase monitoring period was somewhat
similar to the one during the baseline period, when the main concentration of
the feeding and socializing activities occurred at the central portion of the
survey area between Tai O Peninsula and Peaked Hill (Figure 8 of Appendix F).
4.29
During the three-month
monitoring period, four of the 25 dolphin groups was associated with any
operating fishing vessel, including two gill-netters, a single trawler and a
purse-seiner.
Summary
of photo-identification works
4.30
From December 2016 to February
2017, over 3,500 digital photographs of Chinese White Dolphins were taken
during the impact phase monitoring surveys for the photo-identification work.
4.31
In total, 39 individuals
sighted 65 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 them were sighted only once or twice during the three-month period, while
seven individuals were re-sighted 3-5 times during the quarterly period (Appendix III of Appendix F).
Individual
range use
4.32
Ranging patterns of the 39 individuals
identified during the three-month study period were determined by fixed kernel
method, as shown in Appendix V of Appendix F.
4.33
Notably, just a few individual
dolphins (e.g. NL296, NL302) that primarily centered their range use in North
Lantau in the past were found extending their ranges to West Lantau waters
(further south of the HKLR09 alignment), with obvious shifts and expansions of
their range use away from North Lantau waters (Appendix V of Appendix F).
4.34
On the contrary, the majority
of these individuals that primarily centered their range use in West Lantau
were still sighted within their normal range during the present quarterly
period, with some extending their range use into Southwest Lantau waters (Appendix V of Appendix F).
Conclusion
4.35
During the present quarter of
dolphin monitoring, no adverse impact from the activities of the HKLR09 construction
project on Chinese White Dolphins was noticeable from general observations.
4.36
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.
4.37 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.