APPENDIX D  AIR QUALITY MONITORING RESULTS

 

Site: Lamma Power Station Extension

 

Month: December 2005

 

24 hour TSP Measurement:-

Date

TSP concentration (mg/m3)

Weather Information

(From Hong Kong Observatory)

Reservoir

 

(AM1)

East

Gate

(AM2)

Ash Lagoon

 

(AM3)

Tai Yuen Village

(AM4)

Mean Wind Speed

(km/hr)

Prevailing Wind Dir.

()

Mean R.H.

 

(%)

03/12/2005

82

78

81

103

24.7

070

76

09/12/2005

79

76

76

103

29.9

070

78

15/12/2005

143

134

120

114

34.0

020

39

21/12/2005*

230

244

258

196

51.6

020

37

27/12/2005

115

108

160

126

36.3

070

75

29/12/2005

74

70

57

61

20.8

040

83

 

1 hour TSP Measurement:-

Date

Time

TSP concentration (mg/m3)

Reservoir

(AM1)

East Gate

(AM2)

Ash Lagoon

(AM3)

03/12/2005

15:00-15:59

70

68

61

16:00-16:59

70

68

65

17:00-17:59

83

94

91

09/12/2005

15:00-15:59

88

89

89

16:00-16:59

74

80

72

17:00-17:59

77

82

75

15/12/2005

15:00-15:59

74

93

77

16:00-16:59

80

82

94

17:00-17:59

104

124

120

21/12/2005

15:00-15:59

208

207

209

16:00-16:59

269

236

249

17:00-17:59

253

194

242

27/12/2005

15:00-15:59

91

106

92

16:00-16:59

125

113

106

17:00-17:59

129

116

107

 

*    Action Level exceedances were recorded at all air quality monitoring stations.  After investigation, it was found that the RSP concentrations recorded by all EPD monitoring stations on 21 December 2005 were very high.  This suggested that the background dust concentration levels had already been high.  As no significant dusty activity was carried out in Lamma Extension construction site on that day, it is considered that all the action level exceedances were not related to the site activities.  Hence no further action is required.  Subsequent repeated samplings were conducted on 29/12/2005 as required.                                                                                                                                                    

 

                                                                        1-hr TSP                24-hr TSP

                                                                          (mg/m3)                   (mg/m3)

Action Level                                                      340                          190

Limit Level                                                          500                          260

 

 

 

 

 

Calibration:            Calibration details are shown in appendix F.

 

 

Equipment used:

Location

1-hr TSP

24-hr TSP

Reservoir and East Gate

TEOM 1400a

High Volume Air Sampler

Ash Lagoon

Partisol Model 2000 Sampler

Tai Yuen Village

-

MINIVOL Portable Sampler