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.3a   Field Measurement of Dissolved Oxygen (mg/L)  (Revised on 1st October 2000)

(a) Surface and Middle – Dry Season (November – March)

 

SR1

SR2

SR4

SR5

SR6

SR7

Action Level (5%-ile)

4.8*

4.7*

1%-ile

3.9**

4.5**

Limit Level

4.0***

Note:

 

1.         * - the figures 4.8 and 4.7 mg/L represent 5%-ile of Marine Water Quality (MWQ) in Hong Kong from 1996 to 2000

2.         ** - the figures 3.9 and 4.5 mg/L represent 1%-ile of MWQ in Hong Kong from 1996 to 2000

3.         *** - the WQO for DO in non-FCZ

 

 

 

 

 

 

 

(b) Surface and Middle – Wet Season (April – October)

 

SR1

SR2

SR4

SR5

SR6

SR7

Action Level (5%-ile)

4.2*

4.7*

1%-ile

3.9**

4.4**

Limit Level

4.0***

Note:

1.         * - the figures 4.2 and 4.7 mg/L represent 5%-ile of MWQ in Hong Kong from 1996 to 2000

2.         ** - the figures 3.9 and 4.4 mg/L represent 1%-ile of MWQ in Hong Kong from 1996 to 2000

3.         *** - the WQO for DO in non-FCZ

 

 

 

 

 

 

 

(c) Bottom – Dry Season (November – March)

 

SR1

SR2

SR4

SR5

SR6

SR7

Action Level (5%-ile)

5.1*

4.9*

1%-ile

3.7**

4.8**

Limit Level

2.0***

Note:

 

 

 

 

 

 

1.         * - the figures 5.1 and 4.9 mg/L represent 5%-ile of MWQ in Hong Kong from 1996 to 2000

2.         ** - the figures 3.7 and 4.8 mg/L represent 1%-ile of MWQ in Hong Kong from 1996 to 2000

3.         *** - the WQO for DO in non-FCZ

 

(d) Bottom – Wet Season (April – October)

 

SR1

SR2

SR4

SR5

SR6

SR7

Action Level (5%-ile)

2.7*

3.5*

1%-ile

2.3**

3.0**

Limit Level

2.0***

Note:

 

 

 

 

 

 

1.         * - the figures 2.7 and 3.5 mg/L represent 5%-ile of MWQ in Hong Kong from 1996 to 2000

2.         ** - the figures 2.3 and 3.0 mg/L represent 1%-ile of MWQ in Hong Kong from 1996 to 2000

3.         *** - the WQO for DO in non-FCZ

 

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)  (Revised on 1st October 2000)

 

(depth-average)

 

 

 

 

 

 

 

 

SR1

SR2

SR4

SR5

SR6

SR7

 

Maximum

0.008*

0.011*

 

Note:

 

 

1.         * - the figures 0.008 and 0.011 mg/L represent the maximum of MWQ in Hong Kong from 1996 to 2000

 

 

Table C.3e   Total Inorganic Nitrogen (mg/L)  (Revised on 1st October 2000)

(depth-average)

 

 

 

 

 

 

 

SR1

SR2

SR4

SR5

SR6

SR7

Maximum

0.43*

0.50*

Note:

 

 

 

 

 

 

1.         * - the figures 0.43 and 0.50 mg/L represent the maximum of MWQ in Hong Kong from 1996 to 2000