6                    MONITORING RESULTS

6.1              Air Quality

6.1.1        1-hour TSP monitoring was carried out at three monitoring locations during the reporting period.  All monitoring data are presented in Appendix J.  A summary of the measured 1-hour TSP levels is given in Table 6.1.  Graphical presentations of the 1-hour TSP monitoring results for the reporting period and the trend of 1-hour TSP results are shown in Appendix K.

 Table 6.1    Summary of 1-hour TSP Impact Monitoring Results

Location I.D.

1-hour TSP (mg/m3)

Action Level (mg/m3)

Limit Level (mg/m3)

Mean

Range

ASR1

130.0

32.7 – 234.3

318

500

ASR2

169.1

42.9 – 306.5

324

500

ASR3

84.1

4.0 – 166.9

289

500

 

6.1.2        24-hour TSP monitoring was carried out at three monitoring locations during the reporting period.  All monitoring data are presented in Appendix J.  A summary of the measured results is given in Table 6.2.  Graphical presentation of the results and the trend of 24-hour TSP results are shown in Appendix K. 

Table 6.2     Summary of 24-hour TSP Impact Monitoring Results

Location I.D.

24-hour TSP (mg/m3)

Action Level (mg/m3)

Limit Level (mg/m3)

Mean

Range

ASR1

67.6

20.9 – 96.7

163

260

ASR2

98.9

55.9 – 135.5

178

260

ASR3

48.0

26.8 – 72.9

178

260

 

6.1.3        No exceedances of the Action/Limit Levels of 1-hour and 24-hour TSP were recorded at ASR1, ASR2 and ASR3 during the reporting period.  The wind data monitoring results recorded during the reporting period are summarized in Appendix L.

Observations

6.1.4        Several significant dust sources were identified during the reporting period and they were mainly contributed by the following activities:

i.           excavation;

ii.          other construction activities nearby; and

iii.        on/off road traffic dust.

 

6.2              Noise

6.2.1        In accordance with the approved EM&A Manual no noise monitoring was carried out in the presence of fog, rain and wind with a steady speed exceeding 5m/s, or wind gust exceeding 10m/s.  Furthermore, an additional 3dB(A) facade correction for free field measurements were made for all monitoring locations.

6.2.2        In order to assess the construction noise impact effectively for all noise monitoring locations (NSR1 to NSR3) from the Phase 1 Contract, an adjustment approach was adopted since 1st March 2005 and had been consulted with EPD to audit merely the construction noise levels against the statutory noise limits. The measured noise levels were adjusted with the corresponding baseline levels in order to facilitate the interpretation of the construction noise levels and this in turn would determine the actual construction noise impact contributed solely by the Phase 1 construction activities. No adjustment will be made on the measured noise level, if the measured noise level is lower or equal to the corresponding baseline level.

Normal Hour Monitoring

6.2.3        Daytime noise monitoring was carried out at all noise monitoring stations during the reporting period.  All corrected noise levels are presented in Appendix M1.  A summary of the results is given in Table 6.3.  Graphical presentation of the monitoring results for the reporting period and the trend of monitoring results are shown in Appendix N1.   

Table 6.3 Summary of Corrected Impact Noise Levels for Normal Hour Monitoring

Daytime

0700-1900 hrs on normal weekdays

Measured Noise Level1,dB(A),

(Range)

Construction Noise Level, dB(A) (Range)

Limit Level dB(A)

Leq(30min)

L10(30min)

L90(30min)

Leq(30min)

Leq(30min)

NSR1

62.3 – 63.2

63.5 – 64.7

59.7 – 62.1

-  2

75

NSR2

68.9 – 77.8

70.8 – 81.0

59.5 – 70.4

66.1 – 74.8 3

75

NSR3

66.4 – 70.6

67.8 – 71.8

64.7 – 68.2

59.7 – 68.6 3

75

1 Additional 3dB (A) faηade correction was made to the Free-field measurements.

2 No adjustments were made on all measured noise levels, since corresponding baseline level ≥ measured noise level.

3 No adjustments were made on some of the measured noise levels, since corresponding baseline level ≥ measured noise level. The measured noise levels were mainly dominated by local traffic noise and the construction noise generated from the Phase 1 Contract was not noticeable at NSR according to the field study record.

 

Observations

6.2.4        The major noise sources identified during the normal hour in this reporting period were dominated by traffic noise from adjacent roads.  Occasionally construction noise such as on/off site traffic, concrete breaking and excavation were noticeable at NSR2.

Restricted Hour Monitoring

6.2.5        Construction works were carried out at site areas P1-SA1, P1-SA6, P1-SA8 and P1-SA9 during evening-time (i.e. 1900 to 2300 hours) and public holidays (i.e. 0700 to 1900 hours on holidays) of which noise monitoring was conducted at all NSRs.

6.2.6        Construction works were carried out at site area P1-SA1 during night time (2300 to 0700 hours on the next day) of which noise monitoring was conducted at the closest monitoring station, NSR2.

6.2.7        All facade corrected noise levels are presented in Appendix M2.  A summary of the results is given in Table 6.4.  Graphical presentation of the monitoring results for the reporting period and the trend of the monitoring results are shown in Appendix N2. 

 

Table 6.4 Summary of Corrected Impact Noise Levels for Restricted Hour Monitoring

Evening-time

1900-2300 hrs

Measured Noise Level1,dB(A),

(Range)

Construction Noise Level, dB(A) (Range)

Limit Level dB(A)

Leq(5min)

L10(5min)

L90(5min)

Leq(5min)

Leq(5min)

NSR1

56.7 – 61.8

57.4 – 64.1

54.7 – 59.5

– 2

70

NSR2

70.5 – 74.8

72.5 – 77.4

63.4 – 70.0

62.2 – 69.5 3

70

NSR3

65.3 – 68.8

66.4 – 70.0

63.6 – 67.6

49.2 – 66.3 3

70

Night-time

(2300-0700 hrs of next day)

Measured Noise Level1,dB(A),

(Range)

Construction Noise Level, dB(A) (Range)

Limit Level dB(A)

Leq(5min)

L10(5min)

L90(5min)

Leq(5min)

Leq(5min)

NSR1

No restricted hour monitoring was carried out

55

NSR2

61.3 – 68.1

63.0 – 71.4

58.2 – 62.6

54.2 3

55

NSR3

No restricted hour monitoring was carried out

55

Public Holiday

(0700-1900 hrs on holiday)

Measured Noise Level1,dB(A),

(Range)

Construction Noise Level, dB(A) (Range)

Limit Level dB(A)

Leq(5min)

L10(5min)

L90(5min)

Leq(5min)

Leq(5min)

NSR1

59.4 – 65.9

61.1 – 67.2

57.2 – 60.2

49.5 3

70

NSR2

69.0 – 76.0

70.6 – 78.2

60.6 – 68.9

59.3 – 69.5 3

70

NSR3

66.3 – 68.4

67.5 – 70.2

64.3 – 66.7

51.7 – 59.5 3

70

1 Additional 3dB (A) faηade correction was made to the Free-field measurements.

2 No adjustments were made on all measured noise levels, since corresponding baseline level ≥ measured noise level.

3 No adjustments were made on some of the measured noise levels, since corresponding baseline level ≥ measured noise level. The measured noise levels were mainly dominated by local traffic noise and the construction noise generated from the Phase 1 Contract was not noticeable at NSR according to the field study record.

Observations

6.2.8        The major noise sources during the restricted hour monitoring were dominated by the traffic noise from Route 3 and local traffic network (such as Container Port Road).