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 |
||||
|
June 2013 |
AMS1 |
51 |
17 - 86 |
381 |
500 |
|
AMS4 |
57 |
18 - 99 |
352 |
||
|
July 2013 |
AMS1 |
33 |
15 - 51 |
381 |
|
|
AMS4 |
37 |
23 - 56 |
352 |
||
|
August 2013 |
AMS1 |
44 |
19 - 103 |
381 |
|
|
AMS4 |
44 |
19 - 68 |
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 |
||||
|
June 2013 |
AMS1 |
29 |
11 - 49 |
170 |
260 |
|
AMS4 |
31 |
19 - 48 |
171 |
||
|
July 2013 |
AMS1 |
15 |
6 - 20 |
170 |
|
|
AMS4 |
18 |
8 - 25 |
171 |
||
|
August 2013 |
AMS1 |
25 |
9 - 50 |
170 |
|
|
AMS4 |
31 |
18 - 52 |
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 |
N/A |
|
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 |
|||
|
June 2013 |
NMS1 |
70 |
65 – 72 |
75 dB(A) |
|
NMS4 |
63 |
52 – 68 |
||
|
July 2013 |
NMS1 |
68 |
64 – 69 |
|
|
NMS4 |
58 |
56 – 59 |
||
|
August 2013 |
NMS1 |
71 |
69 – 72 |
|
|
NMS4 |
60 |
50 – 62 |
||
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 June
to August 2013, 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 191.00
km of survey effort was collected, with 96.6% 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 126.37 km, while the effort on secondary lines was 64.63
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-1.
4.10
During the six
sets of monitoring surveys in June to August 2013, a total of 53
groups of 182 Chinese White Dolphins were sighted. All except seven
sightings were made during on-effort search. Thirty-three on-effort
sightings were made on primary lines, while another 13
on-effort sightings were made on secondary lines. Summary
table of the dolphin sightings is shown in Appendix
II of Appendix F-1.
Distribution
4.11
Distribution of dolphin sightings made during
monitoring surveys in June to August 2013 is shown in Figure 1 of Appendix F-1. The dolphin groups were evenly
distributed throughout the WL survey area, with higher concentrations near Kai
Kung Shan, Peaked Hill and Fan Lau.
It appeared that more dolphins were sighted in the southern portion of the
survey area, and they were mostly absent from the inshore waters between Tai O
Peninsula and Kai Kung Shan.
4.12
The sighting distribution of dolphins in the
present quarter was largely similar to the one during baseline period, but it appears
that more dolphins were sighted in the southern portion of WL survey area,
especially between Peaked Hill and Fan Lau, in the present quarter.
4.13
Notably, quite a few sightings were made in
the vicinity of western portion of the HKLR09 alignment in WL survey area. When examining the HKLR03 dolphin
sighting data collected during the same quarter, dolphins also occurred along
and near the eastern portion of the HKLR09 alignment in NWL survey area (Figure 2 of Appendix F-1). It appeared that dolphins occurred as
frequently in the impact phase monitoring period as in the baseline monitoring
period, and their distribution was not affected by the HKLR09 construction
activities in the present quarter.
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 June to August 2013 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 (both STG and ANI) in the present three-month study period were
63.7% and 56.7% higher 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 was even more intensive than during the baseline
phase.
Table 4.6 Dolphin encounter rates (sightings per 100 km of survey
effort) during the impact monitoring period (June - August 2013)
|
Survey Area |
Dolphin Monitoring |
Encounter rate (STG) |
Encounter rate (ANI) |
|
Primary Lines Only |
Primary Lines Only |
||
|
West Lantau |
(June 6, 2013) |
17.9 |
35.9 |
|
Set 2 (June 17, 2013) |
21.2 |
52.9 |
|
|
Set 3 |
38.7 |
159.5 |
|
|
Set 4 |
35.8 |
153.5 |
|
|
Set 5 |
9.3 |
41.7 |
|
|
Set 6 |
38.5 |
125.0 |
Table 4.7 Comparison of average dolphin encounter rates from
impact monitoring period (June –
August 2013) 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) |
||
|
June - August 2013 |
September- November 2011 |
June - August 2013 |
September- November 2011 |
|
|
West Lantau |
26.89 ± 12.46 |
16.43 ± 7.70 |
94.75 ± 57.61 |
60.50 ± 38.47 |
(Note:
the encounter rates deduced from the baseline monitoring period have been
recalculated based only on the survey effort and on-effort sighting data made
along the primary transect lines under favourable
conditions)
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 (second quarter of the impact phase), the p-value for the differences in average dolphin encounter rates of STG and ANI were 0.111 and 0.965 respectively. Therefore, no significant difference in dolphin encounter rate was detected between the baseline period and the present quarter.
4.17 To facilitate the comparison with the AFCD long-term monitoring results, the encounter rates were also calculated for the present quarter (June-August 2013) using both primary and secondary survey effort. The encounter rates of sightings (STG) and dolphins (ANI) in WL were 24.9 sightings and 87.8 dolphins per 100 km of survey effort respectively.
Group size
4.18 Group size of Chinese White Dolphins ranged from 1-16 individuals per group in WL survey area between June and August 2013. 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 June to August 2013 was slightly smaller than the ones recorded in the 3-month baseline period (Table 4.8).
Table 4.8 Comparison of average dolphin group sizes from
impact monitoring period (June -
August 2013) and baseline monitoring period
(September-November 2011)
|
|
Average Dolphin Group
Size |
|
|
June-August 2013 |
September-November 2011 |
|
|
West Lantau |
3.43
± 2.96 (n = 53) |
3.63
± 2.97 (n = 46) |
4.19 Distribution of dolphins with larger group sizes (more than 5 animals per group) during June through August 2013 is shown in Figure 3 of Appendix F-1. These larger dolphin groups were mostly sighted near the HKLR09 alignment or toward the southern portion of WL survey area (Figure 3 of Appendix F-1). This was different from the baseline period, where more dolphin sightings with larger group sizes occurred near Tai O Peninsula.
Habitat use
4.20 From June to August 2013, the most heavily utilized habitats by the dolphins mainly concentrated near HKLR09 alignment, Kai Kung Shan, Peaked Hill and Fan Lau (Figures 4a and 4b of Appendix F-1). 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.
4.21 When compared with the habitat use pattern recorded during the baseline period, it appears that dolphin densities were higher along and adjacent to the HKLR09 alignment as well as Fan Lau during the present impact phase monitoring period (Figure 5 of Appendix F-1). On the other hand, their densities were lower near Tai O Peninsula during the present quarter, where dolphin densities were the very high during the baseline period.
Mother-calf pairs
4.22 During the three-month impact phase monitoring period, a total of five unspotted calves and five unspotted juveniles (UJ) were sighted in WL survey area. These young calves comprised only 5.5% of all animals sighted, which was slightly lower to the percentage recorded during the baseline monitoring period (6.6%).
4.23 These young calves mainly occurred near the HKLR09 alignment, and scattered in the central and southern portions of WL survey area. Such distribution was different from the baseline period, where more frequent occurrence of calves near Tai O Peninsula was found (Figure 6 of Appendix F-1).
Activities and
associations with fishing boats
4.24 A total of six and two dolphin sightings were associated with feeding and socializing activities respectively during the three-month impact monitoring period, comprising of 3.3% and 1.1% of the total number of dolphin sightings. Both percentages were much lower than the percentages recorded during the baseline period (feeding activity: 13.0%; socializing activity: 6.5%). The very low occurrence of these two activities recorded in the present quarter is of concern, and should be continuously monitored in the upcoming months.
4.25 Distribution of dolphins engaged in different activities during the three-month study period is shown in Figure 7 of Appendix F-1. The feeding and socializing activities were scattered in the northern and southern portions of WL survey area. This was very different from the baseline period, when most feeding and socializing activities were concentrated in the middle portion of the survey area between Tai O Peninsula and Kai Kung Shan (Figure 7 of Appendix F-1).
4.26 During the three-month period, only one sighting of a lone dolphin was found to be associated with an operating purse-seiner, comprising of 1.9% of all dolphin groups. This was much lower than the percentage recorded in baseline period (6.5%) in which all three sightings were associated with operating pair-trawlers. The exceptionally low percentage of fishing boat association during the present and previous impact phase monitoring quarters was probably related to the recent trawl ban being implemented in 2013 in Hong Kong waters.
Summary of photo-identification
works
4.27 From June to August 2013, over 2,000 digital photographs of Chinese White Dolphins were taken during the impact phase monitoring surveys for the photo-identification work.
4.28 In total, 48 individuals sighted 56 times altogether were identified (see summary table in Appendix III of Appendix F-1 and photographs of identified individuals in Appendix IV of Appendix F-1). Most identified individuals were sighted only once or twice during the three-month period, with the exception of three individuals being sighted thrice (WL25, WL68 and WL124).
4.29 During the three-month period, eight females, including CH113, NL123, WL60, WL100, WL120, WL124, WL145 and WL159, were sighted to be accompanied with their calves during their re-sightings.
Individual range use
4.30 Ranging patterns of the 48 individuals identified during the three-month study period were determined by fixed kernel method, and are shown in Appendix V of Appendix F-1.
4.31 Among these 48 individuals, some of them were sighted near the HKLR09 alignment during the present impact monitoring period, and these individual dolphins focused their range use in either North Lantau waters (e.g. NL123, NL188, NL261, L296) or West Lantau waters (e.g. SL47, WL49, WL120, WL124)
4.32 Notably, the ranging patterns of several individuals (e.g. CH38, SL05, SL40, WL130) do not overlap with the HKLR09 alignment at all, but mostly located around the southwestern side of Lantau Island. It is likely that the impact of HKLR09 construction activities will be minimal to these individuals during the impact phase.
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, and the dolphin occurrence in West Lantau survey area remained the same as in the baseline period.
4.34 Nevertheless, dolphin usage in WL region should be continuously monitored, to examine whether it will be affected by the on-going construction activities in relation to the HZMB works.
4.35 The noise monitoring results are summarized in Table 4.9. Detailed monitoring results and graphical presentations of noise monitoring are shown in Appendix F-2. The averaging period was in general from 9am to 6pm, depending on the availability of the data as the monitoring might have temporarily paused due to bad weather or to give way for barge movement.
Table 4.9 Summary Table of Underwater Noise Monitoring
Results during the Reporting Quarter
|
Date |
Pier No. |
Station |
Underwater Noise (dB re
1µPa) |
Period |
||
|
Max |
Average |
Min |
||||
|
11-Jul-13 |
0 |
R3 |
156.8 |
139.8 |
117.7 |
10-18 |
|
12-Jul-13 |
0 |
R3 |
164.6 |
139.7 |
115.4 |
9-18 |
|
15-Jul-13 |
0 |
R3 |
161.6 |
135.3 |
119.7 |
9-18 |
|
16-Jul-13 |
0 |
R3 |
153.9 |
133.6 |
120.5 |
9-18 |
|
17-Jul-13 |
0 |
R3 |
149.8 |
134.4 |
120.1 |
9-18 |
|
18-Jul-13 |
0 |
R3 |
149.9 |
138.4 |
122.5 |
9-18 |
|
19-Jul-13 |
0 |
R3 |
159.1 |
138.8 |
120.3 |
9-18 |
|
22-Jul-13 |
0 |
R3 |
155.2 |
140.0 |
122.2 |
9-18 |
|
23-Jul-13 |
0 |
R3 |
154.8 |
141.9 |
122.4 |
9-18 |
|
24-Jul-13 |
0 |
R3 |
155.1 |
141.2 |
120.8 |
9-18 |
Remarks: All underwater noise
monitoring was conducted during the bored piling activities
Frequency: 70 Hz – 125 kHz
4.36
In July
2013, a total of 12 days of acoustic monitoring surveys were conducted on the 9th,
11th, 12th, 15th, 16th, 17th,
18th, 22nd, 23rd, 24th, 25th
and 26th, when bored piling activities were concurrently conducted. During
those dates, 783.8 km of survey effort were conducted to search for dolphins in
the western and northwestern waters of Lantau. A total of 46 groups, numbering 170
dolphins, were sighted during these surveys. In addition, 52 sound samples with 4.2
hours of recordings were taken from some of these dolphin groups.
4.37 In July 2013, a total of 13 sessions with
74.1 hours of theodolite
tracking were conducted from Shum Wat shore-based
station on the 8th, 9th, 10th, 11th,
12th, 13th, 15th, 17th, 18th,
19th, 23rd, 24th and 29th, when
bored piling activities were concurrently conducted. More than 93% of effort
was conducted in favourable weather conditions during
those days. Dolphins were
successfully tracked from shore on 12 of the 13 days of efforts, and a total of
57 dolphin groups were tracked. A
total of 1,536 fixes of their positions were collected, and another 2,174 fixes
were also made from locations of various vessels (e.g. fishing boats,
high-speed ferries), to examine the level of vessel traffic in the study
area.
4.38 30days of construction-phase underwater
noise monitoring, dolphin behavior monitoring and land-based dolphin behavior
and movement monitoring have been completed in July 2013 according to EM&A
Manual for HKLR. Results analysis is being undertaken and the final results
will be provided in a separate report in September 2013 tentatively.
4.39
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.
4.40
The
amount of wastes generated by the activities of the Contract during the
reporting month is shown in Appendix J.