Appendix C     Action and Limit Levels for Air Quality, Noise, Water Quality Monitoring

 

 

C.1.   Air

 

Table C.1    Action and Limit Levels for 1-hour and 24-hour TSP

 

 

Action Level, mg/m3

Limit Level, mg/m3

1-hour TSP*

340

500

24-hour TSP

190

260

 

T        No Action/Limit Level for 1-hour TSP is applied to AM4 where no real time dust monitor is installed.

 

 

 

C.2.   Noise

 

Table C.2 presents the Action and Limit (AL) levels for construction noise other than percussive piling.

 

Table C.2    AL Levels for Construction Noise (Other than Percussive Piling)

 

Parameters

Action

Limit

Noise Levels at the NSR's at Long Tsai Tsuen/Hung Shing Ye and school within the village of Tai Wan San Tsuen predicted by the noise alarm monitoring system

When one or more documented complaints are received

a.   75 dB(A) in LAeq,30 min (07:00-19:00 hrs on normal weekdays)  (Note 1)

b.   subject to statutory control under the Noise Control Ordinance (07:00-23:00 hrs on holidays and 19:00-23:00 hrs on all other days).  Set to 60 dB(A) in LAeq,5 min

c.   subject to statutory control under the Noise Control Ordinance (23:00­-07:00 hrs of next day).  Set to 45 dB(A) in LAeq,5 min

 

Note:

1.                  For educational institution, the limit level shall be 70 dB(A), reduced to 65 dB(A) during examination periods.

 

 


 

C.3.   Water

 

Table C.3    Action and Limit Levels for Water Quality

 

 

Table C.3a   Field Measurement of Dissolved Oxygen (mg/L)

 

 

(a) Surface and Middle

 

 

 

 

 

 

 

SR1

SR2

SR4

SR5

SR6

SR7

Action Level (5%-ile)

6.0

6.0

6.1

6.0

6.0

6.0

1%-ile

6.0

6.0

6.0

6.0

5.8

5.7

Limit Level

4.0

Note:

 

1.                    All impact monitoring stations were considered to be non-FCZ stations

2.                    Since the calculated 1%-ile results are larger than 4.0 mg/L, therefore the Limit Levels are proposed to be 4.0 mg/L according to the EM&A Manual

 

 

 

 

 

 

 

(b) Bottom

 

 

 

 

 

 

 

SR1

SR2

SR4

SR5

SR6

SR7

Action Level (5%-ile)

5.9

6.0

6.1

6.1

6.1

6.1

1%-ile

5.9

5.9

5.9

5.9

5.7

5.7

Limit Level

2.0

Note:

 

 

 

 

 

 

1.                    Since the calculated 1%-ile results are larger than 2.0 mg/L, therefore the Limit Levels are proposed to be 2.0 mg/L according to the EM&A Manual

 

Table C.3b   Turbidity (NTU)

 

 

 

 

 

(depth-average)

 

 

 

 

 

 

 

SR1

SR2

SR4

SR5

SR6

SR7

Action Level (95%-ile)

17.9

16.3

13.2

17.5

17.2

17.3

Limit Level (99%-ile)

22.8

19.0

13.6

18.3

17.9

21.5

Note:

 

 

 

 

 

 

1.                    The Action Levels can be 95%-ile of baseline data as mentioned above or 120% of upstream control station at the same tide of the same day according to the EM&A Manual

2.                    The Limit Levels can be 99%-ile of baseline data as mentioned above or 130% of upstream control station at the same tide of the same day according to the EM&A Manual.

3.                    During ebb tide, the upstream control stations are C1, C2 and C3 while during flood tide, the upstream control stations are C4 and C5.


 






 

 

 

 

 

 

Table C.3c   Suspended Solids (mg/L)

 

 

 

 

 

(depth-average)

 

 

 

 

 

 

 

 

SR1

SR2

SR3

SR4

SR5

SR6

SR7

95%-ile

16.8

15.3

13.8

17.6

17.5

16.9

17.5

Action Level

16.8

15.3

--

17.6

17.5

16.9

17.5

 99%-ile

18.9

15.5

17.0

19.1

18.4

23.5

19.0

Limit Level

18.9

15.5

100.0

19.1

18.4

23.5

19.0

Note:

 

1.                    No Action Level is applied for SR3 according to the EM&A Manual

2.                    Limit Level of SR3 is 100 mg/L according to the EM&A Manual

3.                    The Action Levels can be 95%-ile of baseline data as mentioned above or 120% of upstream control station at the same tide of the same day according to the EM&A Manual

4.                    The Limit Levels can be 99%-ile of baseline data as mentioned above or 130% of upstream control station at the same tide of the same day according to the EM&A Manual.

5.                    During ebb tide, the upstream control stations are C1, C2 and C3 while during flood tide, the upstream control stations are C4 and C5.

 

 

Table C.3d   Unionized Ammonia (mg/L)

 

 

 

 

(depth-average)

 

 

 

 

 

 

 

SR1

SR2

SR4

SR5

SR6

SR7

Action Level (95%-ile)

0.006

0.005

0.003

0.001

0.001

0.001

99%-ile

0.007

0.005

0.003

0.002

0.001

0.003

Limit Level

0.021

0.021

0.021

0.021

0.021

0.021

Note:

 

1.                    Since the calculated 99%-ile results are smaller than 0.021 mg/L, therefore the Limit Levels are proposed to be 0.021 mg/L according to the EM&A Manual.

 

 

Table C.3e   Total Inorganic Nitrogen (mg/L)

 

 

 

 

(depth-average)

 

 

 

 

 

 

 

SR1

SR2

SR4

SR5

SR6

SR7

Action Level (95%-ile)

0.25

0.23

0.11

0.11

0.11

0.12

99%-ile

0.27

0.25

0.12

0.11

0.11

0.13

Limit Level

0.40

0.25

0.12

0.11

0.11

0.13

Note:

 

 

 

 

 

 

1.                    Since the calculated 99%-ile results for SR2 to SR7 are larger than 0.1 mg/L, therefore the Limit Levels for SR2 to SR7 are proposed to be the calculated 99%-ile data according to the EM&A Manual.

2.                    Since the calculated 99%-ile result for SR1 is smaller than 0.4 mg/L, therefore the Limit Level for SR1 is proposed to be 0.4 mg/L according to the EM&A Manual.