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 |
||||
|
February 2013 |
AMS1 |
77 |
29 – 129 |
381 |
500 |
|
AMS4 |
128 |
60 – 204 |
352 |
||
|
March 2013 |
AMS1 |
59 |
3 - 238 |
381 |
|
|
AMS4 |
59 |
3 - 200 |
352 |
||
|
April 2013 |
AMS1 |
47 |
15 - 97 |
381 |
|
|
AMS4 |
60 |
21 - 108 |
352 |
||
|
May 2013 |
AMS1 |
54 |
23 - 104 |
381 |
|
|
AMS4 |
51 |
19 - 114 |
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 |
||||
|
February 2013 |
AMS1 |
45 |
20 – 70 |
170 |
260 |
|
AMS4 |
51 |
30 – 72 |
171 |
||
|
March 2013 |
AMS1 |
22 |
9 - 60 |
170 |
|
|
AMS4 |
20 |
8 - 42 |
171 |
||
|
April 2013 |
AMS1 |
35 |
9 - 53 |
170 |
|
|
AMS4 |
49 |
24 - 77 |
171 |
||
|
May 2013 |
AMS1 |
32 |
17 - 47 |
170 |
|
|
AMS4 |
37 |
22 - 56 |
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
Appendices 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 |
|||
|
February
2013 |
NMS1 |
65 |
N/A |
75 dB(A) |
|
NMS4 |
59 |
N/A |
||
|
March 2013 |
NMS1 |
68 |
65 – 71 |
|
|
NMS4 |
58 |
56 – 62 |
||
|
April 2013 |
NMS1 |
69 |
66 – 70 |
|
|
NMS4 |
56 |
54 – 59 |
||
|
May 2013 |
NMS1 |
66 |
55 – 74 |
|
|
NMS4 |
58 |
56 – 60 |
||
Remark:
+3dB(A) Façade correction included
N/A:
Only one noise monitoring was conducted in the reporting period, no range of
noise level is provided.
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 February
to May 2013, eight 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 254.95 km of
survey effort was collected, with 90.2% 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 171.08 km, while the effort on secondary lines was 83.87
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 eight sets of monitoring surveys
in February to May 2013, a total of 33 groups of 114 Chinese White Dolphins
were sighted. All except two
sightings were made during on-effort search. Twenty-two on-effort sightings were made
on primary lines, while another nine on-effort sightings were made on secondary
lines. Summary table of the dolphin
sightings is shown in Appendix II of Appendix
F-1.
4.11
For the detailed comparison of dolphin
occurrence and usage of West Lantau survey area
between the impact phase and baseline phase monitoring (i.e. Section 4.12-4.29),
only the quarterly data of March-May 2013 from the impact phase monitoring was
used in the present report to tally with the three month period of baseline
monitoring (September-November 2011).
The three-month period (March-May 2013) is also consistent with
seasonality period as defined in the long-term monitoring dolphin research
conducted by AFCD (Hung 2012, 2013) to allow direct comparison between the
baseline and impact phase monitoring data.
Distribution
4.12
Distribution of dolphin sightings made during
monitoring surveys in March to May 2013 is shown in Figure 1 of Appendix F-1. Most dolphin sightings were made in the
central and southern portions of the survey area, with particular
concentrations near Kai Kung Shan and Fan Lau. A few sightings were also made near Tai
O Peninsula, but only one sighting was made in the northern portion of the
survey area.
4.13
Only one sighting was made in the vicinity of
the HKLR09 alignment in West Lantau survey area, but
it should be noted that this survey area only covers part of the HKLR09
alignment while the other half overlaps with the Northwest Lantau
survey area.
4.14
When compared with the sighting distribution
of dolphins during baseline monitoring surveys in September to November 2011,
it appears that much fewer sightings were made to the north of Tai O Peninsula
while more sightings were made in the southern portion of the survey area in
the present quarter (Figure 1 of Appendix
F-1). In addition, more
sightings were made in the offshore waters of West Lantau
during the baseline period than the impact monitoring period (Figure 1 of Appendix F-1).
4.15
It appears that the dolphins may have
temporarily shifted their distribution further south during the present impact
monitoring period. It remained to
be confirmed whether they have been affected by the HKLR09 construction
activities in the present quarter to result in such shift in distribution, or
such shift is related to seasonal fluctuation in dolphin habitat use. This will be continuously monitored and
further assessed in the next quarterly period.
Encounter rate
4.16
During the four-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 2013
(encounter rates from February 2013 was excluded in the comparison to tally
with the three-month period of baseline monitoring) were also compared with the
ones deduced from the baseline monitoring period (September – November 2011) (Table 4.7).
4.17
In WL, the average dolphin encounter rates
(both STG and ANI) in the present three-month study period were very similar to
the ones recorded in the 3-month baseline period, indicating the dolphin usage
during this impact phase monitoring period in this survey area was maintained
at the same level as in the baseline phase.
Table 4.6 Dolphin encounter rates (sightings per 100 km of survey
effort) during the impact monitoring period (February - May 2013)
|
Survey Area |
Dolphin Monitoring |
Encounter rate (STG) |
Encounter rate (ANI) |
|
Primary Lines Only |
Primary Lines Only |
||
|
West Lantau |
4.6 |
18.4 |
|
|
Set 2
(February 25,2013) |
0.0 |
0.0 |
|
|
Set 3 |
19.4 |
62.9 |
|
|
Set 4 |
29.2 |
110.8 |
|
|
Set 5 |
11.2 |
61.5 |
|
|
Set 6 |
9.2 |
22.9 |
|
|
Set 7 |
9.8 |
34.3 |
|
|
Set 8 |
21.5 |
59.1 |
Table 4.7 Comparison of average dolphin encounter rates from
impact monitoring period (March-May 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) |
||
|
March
- May 2013 |
September- November 2011 |
March - May 2013 |
September- November 2011 |
|
|
West Lantau |
16.70 ± 8.00 |
16.43 ± 7.70 |
58.59 ± 30.37 |
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)
4.18
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 (first quarter of the impact phase), the p-value
for the differences in average dolphin encounter rates of STG and ANI were 0.9550
and 0.9259 respectively based
on the alpha value of 0.05. Therefore, no significant difference in
dolphin encounter rate was detected between the baseline period and the present
quarter.
4.19 To
facilitate the comparison with the AFCD long-term monitoring results, the encounter
rates were also calculated for the present quarter (March-May 2013) using both
primary and secondary survey effort.
The encounter rates of sightings (STG) and dolphins (ANI) in WL were
15.41 sightings and 56.49 dolphins per 100 km of survey effort respectively.
Group size
4.20 Group
size of Chinese White Dolphins ranged from 1-12 individuals per group in WL
survey area between March and May 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 sizes in the West
Lantau region during March to May 2013 was slightly lower
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 (March-May 2013) and baseline monitoring period
(September-November 2011)
|
|
Average Dolphin Group
Size |
|
|
March-May 2013 |
September-November 2011 |
|
|
West Lantau |
3.44 ± 3.12 (n = 32) |
3.63 ± 2.97 (n = 46) |
4.21 Distribution
of dolphins with larger group sizes (more
than 5 animals per group) during March through May 2013 is shown in Figure 2 of Appendix F-1. These
larger dolphin groups were mostly sighted between Kai Kung Shan and Fan Lau
(Figure 2 of Appendix F-1). This was noticeably different from the
baseline period, when more dolphin sightings were larger group sizes occurred
near Tai O Peninsula and just to the south of the HKLR09 alignment (Figure 2 of
Appendix F-1).
Habitat use
4.22 From
March to May 2013, the most heavily utilized habitats by the dolphins mainly
concentrated near Kai Kung Shan, Peaked Hill and Tai O (Figures 3a and 3b 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 still 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.
4.23 When
compared with the habitat use pattern recorded during the baseline period, it
appears that the density of dolphins in the upper portion of WL survey area was
much lower during the impact monitoring period, with an apparent shift to the
southern side of the survey area (Figure
4 of Appendix F-1). Notably, several grids (22C-D, 23C-E)
recorded high dolphin densities in the vicinity of the HKLR09 alignment during
the baseline period, but these five
grids recorded either no dolphin or very low dolphin density during the impact
phase monitoring period (Figure 4 of
Appendix F-1). Notably,
Grid 21F also recorded very high dolphin density during the baseline
period. However, as this grid is
situated in the Northwest Lantau survey area and
under the jurisdiction of another HZMB EM&A contracts (i.e. HKBCF and
HKLR03), and therefore will not be included in this report that solely focuses
on West Lantau survey area.
Mother-calf pairs
4.24 During
the three-month impact phase monitoring period, a total of four unspotted
juveniles (UJ) were sighted in WL survey area, and the mothers of two of these
UJs were identified (i.e. WL44 and WL94).
These young calves comprised only 3.6% of all animals sighted, which was
much lower to the percentage recorded during the baseline monitoring period (6.6%). Moreover, two unspotted calves (UC) were
sighted during the three-month baseline period, but no UC was sighted at all
during the present impact monitoring period.
4.25 These
four young calves only occurred between Peaked Hill and Fan Lau during
March-May 2013, which was noticeably different from the frequent occurrence of
calves near Tai O Peninsula during the baseline period (Figure 5 of Appendix F-1).
Activities and
associations with fishing boats
4.26 A
total of six and three dolphin sightings were associated with feeding and
socializing activities respectively during the three-month impact monitoring
period, comprising of 18.8% and 9.4% of the total number of dolphin
sightings. Both percentages were
higher than the percentages recorded during the baseline period (feeding
activity: 13.0%; socializing activity: 6.5%). Only a lone dolphin was engaged in
traveling activity in the present impact monitoring period, while this behaviour was not observed at all during the baseline
period.
4.27 Distribution
of dolphins engaged in different activities during the three-month study period
is shown in Figure 6 of Appendix F-1. The feeding and socializing activities
were scattered between Tai O Peninsula and Fan Lau with no apparent
concentration. This is slightly
different from the baseline period, when most feeding and socializing
activities were concentrated between Tai O Peninsula and Kai Kung Shan (Figure
6 of Appendix F-1).
4.28 During
the three-month period, only one dolphin group were found to be associated with
an operating gill-netter, comprising of 3.1% of all dolphin groups. This was lower than the percentage
recorded in baseline period (6.5%) in which all three sightings were associated
with operating pair-trawlers. The
low percentage of fishing boat association during the impact phase monitoring was
likely related to the recent trawl ban being implemented in 2013 in Hong Kong
waters.
Summary of photo-identification
works
4.29 From
February to May 2013, over 4,000 digital photographs of Chinese White Dolphins
were taken during the impact phase monitoring surveys for the
photo-identification work.
4.30 In
total, 38 individuals sighted 61 times altogether were identified (see summary
table in Appendix III of Appendix F-1). Most identified individuals were sighted
only once or twice during the four-month period, with the exception of four
individuals being sighted thrice (WL116, WL130, WL142 and WL201), and three
individuals being sighted four times (SL05, WL25 and WL42).
4.31 During
the four-month period, two females (WL44 and WL94) were sighted to be
accompanied with their calves during their re-sightings.
Individual range use
4.32 Ranging
patterns of the 38 individuals identified during the four-month study period
were determined by fixed kernel method, and are shown in Appendix IV of Appendix F-1.
4.33 Among
these 38 individuals, only a few were sighted near the HKLR09 alignment during
the present impact monitoring period, and these individual dolphins mainly
focused their range use in North Lantau waters (e.g.
CH34, NL37, WL05) instead of West Lantau waters.
4.34 On
the contrary, most individuals were sighted far away from the HKLR09 alignment,
which coincided with the infrequent occurrence of dolphins in the upper portion
of West Lantau survey area during the present
quarter. The 95%UD ranges of these
individuals overlapped with HKLR09 alignment (e.g. CH108, WL25, WL42, WL72, WL116) where they used to occur in the past. It is possible that they may have
shifted their range use further south in light of the increased disturbance
from the construction activities.
4.35 Notably,
the ranging patterns of several individuals (e.g. CH38, SL05, WL84, WL144) 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
4.36 During
this quarter of dolphin monitoring, no adverse impact from the activities of
this 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.
4.37 Although
the average dolphin encounter rates in the present three-month study period
were similar to the ones in the three-month baseline monitoring period, the
spatial occurrence of dolphins appeared to be noticeably different between the
two periods, with lower usage of the area to the north of Tai O Peninsula (i.e.
the vicinity of HKLR09 construction site) during the present impact monitoring
period.
4.38 Dolphin
usage in West Lantau waters should be continuously
monitored, to examine whether such avoidance of the northern portion of the
study area by the dolphins will continue in the upcoming quarter.
4.39
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 |
||||
|
13-Mar-13 |
48 |
R1 |
159.6 |
129.3 |
108.3 |
10-17 |
|
14-Mar-13 |
48 |
R1 |
157.5 |
126.7 |
110.4 |
9-17 |
|
15-Mar-13 |
48 |
R1 |
163.0 |
128.5 |
108.7 |
9-17 |
|
*18-Mar-13 |
48 |
R1 |
152.3 |
125.0 |
109.4 |
9-18 |
|
*19-Mar-13 |
48 |
R1 |
154.2 |
121.4 |
109.9 |
9-15 |
|
*20-Mar-13 |
48 |
R1 |
145.0 |
125.5 |
112.2 |
13-20 |
|
*21-Mar-13 |
48 |
R1 |
162.8 |
122.8 |
108.7 |
9-18 |
|
*22-Mar-13 |
48 |
R1 |
144.9 |
121.6 |
108.9 |
9-18 |
|
*23-Mar-13 |
48 |
R1 |
161.5 |
122.9 |
110.5 |
9-17 |
|
*25-Mar-13 |
48 |
R1 |
151.5 |
125.6 |
109.4 |
9-16 |
|
26-Mar-13 |
52 |
R2 |
165.9 |
128.5 |
111.2 |
9-10,
14-15 |
|
*27-Mar-13 |
52 |
R2 |
152.1 |
127.9 |
110.7 |
9-18 |
|
*28-Mar-13 |
52 |
R2 |
156.5 |
133.3 |
112.2 |
12-16 |
|
*2-Apr-13 |
52 |
R2 |
155.8 |
129.5 |
110.8 |
9-18 |
|
*3-Apr-13 |
52 |
R2 |
147.1 |
125.5 |
111.8 |
9-18 |
|
*5-Apr-13 |
52 |
R2 |
156.7 |
129.8 |
111.6 |
9-17 |
|
*8-Apr-13 |
52 |
R2 |
157.2 |
128.7 |
109.4 |
9-18 |
|
*9-Apr-13 |
52 |
R2 |
155.2 |
130.3 |
112.3 |
9-18 |
|
*10-Apr-13 |
52 |
R2 |
146.6 |
129.1 |
112.7 |
9-16 |
|
11-Apr-13 |
52 |
R2 |
145.0 |
128.8 |
111.0 |
9-17 |
|
*25-Apr-13 |
48 |
R1 |
156.6 |
129.8 |
112.3 |
9-18 |
|
*26-Apr-13 |
48 |
R1 |
163.9 |
129.3 |
113.9 |
9-18 |
|
*27-Apr-13 |
52 |
R2 |
149.8 |
134.0 |
118.5 |
9-17 |
|
*29-Apr-13 |
52 |
R2 |
160.1 |
133.9 |
113.8 |
9-18 |
|
*30-Apr-13 |
48 |
R1 |
146.9 |
132.3 |
112.9 |
9-14,
16-18 |
Remarks: * Underwater noise
monitoring was conducted during the bored piling activities
Frequency: 70 Hz – 125 kHz
with bored piling
4.40
In March
2013, a total of 10 days of acoustic monitoring surveys were conducted on the
18th, 19th, 20th, 21st, 22nd, 23rd, 25th, 27th, 28th and 29th, when bored
piling activities were concurrently conducted During those dates, 623.6 km of survey
effort were conducted to search for dolphins in the western and northwestern
waters of Lantau. A total of 18 groups, numbering 45
dolphins, were sighted during these surveys. In addition, 11 sound samples with 58.3
hours of recordings were taken from some of these dolphin groups.
4.41 In
April, 524.4 km of survey effort were conducted to search for dolphins in the
western and northwestern waters of Lantau. A total of four groups, numbering seven
dolphins, were sighted during these surveys. In addition, two sound samples with 10
minutes of recordings were taken from some of these dolphin groups.
without bored piling
4.42
In
March 2013, a total of 13 days of acoustic monitoring surveys were conducted on
the 6th, 7th, 8th, 9th, 11th, 12th, 13th, 14th, 15th, 16th, 17th, 24th and
30th, when no bored piling activities were conducted. During those dates, 820.0 km of survey
effort were conducted to search for dolphins in the western and northwestern
waters of Lantau. A total of 23 groups, numbering 72
dolphins, were sighted during these surveys. In addition, 21 sound samples with 102.2
hours of recordings were taken from some of these dolphin groups. Moreover, the EARs were deployed since
February 25th, 2013 at Fan Lau (site B1) and near the bridge alignment (Site
B2), which will be recovered at the end of the construction phase
monitoring.
4.43 In March 2013, a total of 9 sessions with
49.87 hours of theodolite tracking were conducted
from Shum Wat shore-based station on the 18th, 19th,
20th, 21st, 22nd, 23rd, 25th, 27th and 28th, when bored piling activities were
concurrently conducted. More than
80% of effort was conducted in favourable weather
conditions during those days.
Dolphins were successfully tracked from shore on six of the nine days of
efforts, and a total of eight dolphin groups were tracked. A total of 124 fixes of their positions
were collected, and another 2,862 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.
4.44
In April 2013, a total of 9 sessions with 52.67
hours of theodolite tracking were conducted from Sham
Wat shore-based station on April 1st, 2nd,
4th, 5th, 7th, 8th, 9th,
10th and 11th April 2013. More than 80% of effort
was conducted in favourable weather conditions during
those days. Dolphins were
successfully tracked from shore on two of the nine days of efforts, and a total
of three dolphin groups were tracked.
A total of 93 fixes of their positions were collected, and another 2,314
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.
without bored piling
4.45 In March 2013, a total of 13 sessions with
76.75 hours of theodolite tracking were conducted
from Shum Wat shore-based station on the 6th, 7th,
9th, 10th, 11th, 12th, 13th, 14th, 15th, 16th, 17th, 24th and 30th, when no
bored piling activities were conducted.
More than 80% of effort was conducted in favourable
weather conditions during those days.
Dolphins were successfully tracked from shore on 6 of 13 days of
efforts, and a total of 11 dolphin groups were tracked. A total of 240 fixes of their positions
were collected, and another 3,716 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.
4.46
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.
4.47
The
amount of wastes generated by the activities of the Contract during the
reporting month is shown in Appendix J.