Appendix B - Action and Limit Levels

 

Table B-1       Action and Limit Levels for 1-hour TSP

Monitoring station

Action Level (ug/m3)

Limit Level (ug/m3)

KTN-DMS4

297

500

FLN-DMS1

303

FLN-DMS3

301

 

 

 

 

 

 

 

Table B-2       Action and Limit Levels for 24-hour TSP

Monitoring station

Action Level (ug/m3)

Limit Level (ug/m3)

KTN-DMS4

192

260

FLN-DMS1

150

FLN-DMS3

165

 

 

 

 

 

 

 

 

Table B-3       Action and Limit Levels for Construction Noise

Time Period

Action Level

Limit Level

0700-1900 hrs on normal weekdays

When one documented complaint is received

75 dB(A) *

 

 

 

 

 

 

Noted:

If works are to be carried during restricted hours, the conditions stipulated in the construction noise permit issued by the Noise Control Authority have to be followed.

(*)           reduce to 70 dB(A) for schools and 65 dB(A) during school examination periods.

 

Table B-4.1    Action and Limit Levels for Water Quality Monitoring(1)

Parameters

Action Level

Limit Level

DO in mg/L (depth average)#+

5 percentile of baseline data.

4 mg/L or 1 percentile of baseline data.

SS in mg/L (depth averaged)*&

95 percentile of baseline data or 120% of upstream control station.

20 mg/L or 99 percentile of baseline data or 130% of upstream control station.

Turbidity in NTU (depth averaged)*^

95 percentile of baseline data or 120% of upstream control station.

99 percentile of baseline data or 130% of upstream control station.

Unionized ammonia in mg/L

(depth averaged)*~

95 percentile of baseline data or 120% of upstream control station.

0.021mg/L or 99 percentile of baseline data or 130% of upstream control station.

Nitrate nitrogen in mg/L

(depth averaged)*^

95 percentile of baseline data or 120% of upstream control station.

99 percentile of baseline data or 130% of upstream control station.

Orthophosphate in mg/L (depth averaged)*^

95 percentile of baseline data or 120% of upstream control station.

99 percentile of baseline data or 130% of upstream control station.

 

Remarks:

# AL of DO is 5 percentile of baseline data or level at control station at same tide of the same day (whichever lower) and LL of DO is 4.0 mg/L or level at control station at same tide of the same day (whichever lower);

+ 1 percentile of baseline data were adopted for LL for DO as those levels were greater than 4 mg/L;

* AL is 120% of control station’s level at the same tide of the same day when depth average greater than 95 percentile of baseline data;

^ LL is 130% of control station’s level at the same tide of the same day when depth average greater than 99 percentile of baseline data.

~ LL is 130% of control station’s level at the same tide of the same day when depth average greater than 99 percentile of baseline data or 0.021mg/L.

& LL is 130% of control station’s level at the same tide of the same day when depth average greater than 99 percentile of baseline data or 20mg/L.

 

Table B-4.2    Summary of Baseline Water Quality Monitoring Results (KTN NDA)(1)

Monitoring Parameter

                       Location

 

 

Parameter

KTN-CS1

Max

Min

Average

5 Percentile

1 Percentile

DO in mg/L

7.79

6.28

6.82

6.32

6.28

 

Max

Min

Average

95 Percentile

99 Percentile

Turbidity in NTU

72.4

4.59

10.88

62.2

72.2

Suspended Solid in mg/L

74

2

9

60

73

Unionized ammonia in mg/L

0.0005

0.0001

0.0003

0.0004

0.0005

Nitrate nitrogen in mg/L

0.52

0.09

0.27

0.50

0.52

Orthophosphate in mg/L

0.19

0.01

0.10

0.17

0.19

 

Monitoring Parameter

                       Location

 

 

Parameter

KTN-IS1

Max

Min

Average

5 Percentile

1 Percentile

DO in mg/L

8.08

4.71

6.83

6.14

5.02

 

Max

Min

Average

95 Percentile

99 Percentile

Turbidity in NTU

44.56

4.57

8.63

38.98

44.56

Suspended Solid in mg/L

35

2

6

31

35

Unionized ammonia in mg/L

0.0006

0.0001

0.0004

0.0005

0.0006

Nitrate nitrogen in mg/L

0.57

0.09

0.29

0.54

0.57

Orthophosphate in mg/L

0.14

0.03

0.09

0.13

0.14

 

Note:

(1) The Action and Limit Levels for Water Quality Monitoring and the Summary of Baseline Water Quality Monitoring Results are according to pre-construction ET’s Updated EM&A Manual and Baseline Water Quality Monitoring Report (KTN & FLN NDA).

 

Table B-5       Action and Limit Levels for Ambient Arsenic Monitoring

Parameter

Action Level

Limit Level

Ambient Arsenic Concentration

9.36ng/m3

- 80% of 11.7ng/m3 – the highest ambient arsenic concentration predicted during the construction phase with mitigation measures implemented)

11.7ng/m3

- the highest ambient arsenic concentration predicted during the construction phase with mitigation measures implemented

 

 

 

 

 

 

 

Table B-6       Action level in the event of LFG being detected

 Parameter

Monitoring Results

Actions

O2

<19% v/v

Increase underground ventilation to restore O2 to >19% v/v

<18% v/v

Stop works, evacuate all personnel, prohibit entry, and increase ventilation to restore O2 level to >19%

CH4

>10% LEL

Prohibit hot works, increase ventilation to restore CH4 to <10% LEL

>20% LEL

Stop works, evacuate all personnel, increase ventilation further to restore CH4 to <10% LEL

CO2

>0.5% v/v

Increase ventilation to restore C O2 to <0.5% v/v

>1.5% v/v

Stop works, evacuate all personnel, increase ventilation further to restore CO2 to <0.5%

 

Table B-7.1 Action and Limit Levels and Responses to Evidence of Disturbance to Waterbirds using in Ng Tung, Sheung Yue and Shek Sheung Rivers

Action Level

Response

Limit Level

Response

Construction Phase

Decline in numbers of all waterbird species relative to numbers during Baseline Monitoring

such that the Action

Level response is

triggered.

Investigate cause and if

cause identified as

related to NDAs project

instigate remedial

action to remove or

reduce source of

disturbance.

Decline in numbers

of all waterbird

species relative to

numbers during

Baseline Monitoring

such that the Limit

Level response is

triggered.

Investigate cause

and if caused

identified as related

to NDAs project

instigate remedial

action. Review and

adjust LVNP

management

measures to improve

conditions for

affected species.

Decline in numbers

of any one waterbird

species occurring in

significant numbers*

during Baseline

Monitoring such that

the Action Level

response is

triggered.

Investigate cause and if

cause identified as

related to NDAs project

instigate remedial

action to remove or

reduce source of

disturbance.

Decline in numbers

of any one waterbird

species occurring in

significant numbers*

during Baseline

Monitoring such that

the Limit Level

response is

triggered.

Investigate cause

and if caused

identified as related

to NDAs project

instigate remedial

action. Review and

adjust LVNP

management

measures to improve

conditions for

affected species.

Operational Phase

Decline in numbers of all waterbird species relative to numbers during Baseline Monitoring such that the Action Level response is triggered.

Investigate cause and if cause identified as related to NDAs review and adjust LVNP management measures to improve conditions for affected species in LVNP.

Decline in numbers of all waterbird species relative to numbers during Baseline Monitoring such that the Limit Level response is triggered.

Investigate cause and if cause identified as related to NDAs consider and implement additional mitigation measures (e.g. additional screening and screen planting, adjustments to infrastructure design).

Decline in numbers of any one waterbird species occurring in significant numbers* during Baseline Monitoring such that the Action Level response is triggered.

Investigate cause and if cause identified as related to NDAs review and adjust LVNP management measures to improve conditions for affected species.

Decline in numbers of any one waterbird species occurring in significant numbers* during Baseline Monitoring such that the Limit Level response is triggered.

 

 

 

Investigate cause and if cause identified as related to NDAs consider and implement additional mitigation measures (e.g. additional screen planting, adjustments to infrastructure design).

* Whether numbers are significant will depend on species and season and should be determined following collection and evaluation of Baseline survey data.

 

Table B-7.2 Action and Limit Levels and Responses to Evidence of Declines in Aquatic Fauna

Action Level

Response

Limit Level

Response

Construction Phase

Reduction in species diversity such that Action Level response is triggered.

Investigate cause and if cause identified as related to Project instigate remedial action to remove or reduce source of disturbance.

Reduction in taxa diversity such that Limit Level response is triggered.

Investigate cause and if caused identified as related to Project instigate remedial action.

Operational Phase

Reduction in species such that Action Level response is triggered.

Investigate cause and if cause identified as related to Project review and adjust LVNP management measures to improve conditions for affected species.

Reduction in taxa diversity response is triggered.

Investigate cause and if cause identified as related to Project consider and implement additional mitigation measures.

* Whether numbers are significant will depend on species and season. Significance threshold for each species should be reviewed following collection of Baseline survey data.

 

Table B-7.3 Action and Limit Levels and Responses to Evidence of Declines in non-aquatic Fauna

Action Level

Response

Limit Level

Response

Construction Phase

Reduction in species diversity such that Action Level response is triggered.

Investigate cause and if cause identified as related to Project instigate remedial action to remove or reduce source of disturbance.

Reduction in taxa diversity such that Limit Level response is triggered.

Investigate cause and if caused identified as related to Project instigate remedial action.

Operational Phase

Reduction in species such that Action Level response is triggered.

Investigate cause and if cause identified as related to Project review and adjust LVNP management measures to improve conditions for affected species.

Reduction in taxa diversity response is triggered.

Investigate cause and if cause identified as related to Project consider and implement additional mitigation measures.

* Whether numbers are significant will depend on species and season. Significance threshold for each species should be reviewed following collection of Baseline survey data.