2 AIR QUALITY

2.1 Introduction

2.2 Air Quality Parameters

2.3 Monitoring Equipment

2.4 Laboratory Measurement / Analysis

2.5 Monitoring Locations

2.6 Baseline Monitoring

2.7 Impact Monitoring of Construction Air Quality Impact

2.8 Impact Monitoring of Operation Air Quality Impact

2.9 Environmental Quality Performance Limits

2.10 Event and Action Plan

2.11 Mitigation Measures

2 AIR QUALITY

2.1 Introduction

2.1.1 In this section, the general requirements, methodology, equipment, monitoring locations, criteria and protocols for the monitoring and audit of air quality impacts during the construction phase of all WDII and CWB works, including entrustment works from HyD, are presented. The specific air quality EM&A requirements for each of Designated Projects are defined in Appendices D to I. As the construction dust is the prime concern, TSP levels shall be monitored to evaluate the dust impact during the construction phase.

2.1.2 The findings of the EIA also indicated that the existing odour sources at CBTS would have potential odour impact on the planned Air Sensitive Receivers (ASR) under WDII Project during operation phase of the Project. Odour monitoring would be required to determine the effectiveness of mitigation measures and monitor the residual odour impact on the planned ASR.

2.1.3 There will be no exceedance of AQOs at the sensitive receivers and hence air quality monitoring is considered not necessary during the operation phase of the Project. Nevertheless, the operator for the proposed CWB tunnel, HyD, will conduct air quality monitoring for the operation performance of the EVB ventilation shaft. Details of the air quality monitoring should be formulated in the detailed design stage subject to agreement between EPD and HyD.

2.1.4 During operational phase, this Project will not create any new odour source. However, odour nuisance associated with the Causeway Bay Typhoon Shelter (CBTS) is an existing environmental problem. In order to improve the environment, this Project will take the opportunities to mitigate the potential sources of odour nuisance within the Project area so as to alleviate this existing environmental problem as well as to provide an acceptable environment for the future land uses within the project area (including the proposed open space at the northern breakwater). Enhancement measures have been formulated to alleviate this existing odour problem. With the implementation of the enhancement measures, the predicted odour levels in the vicinity of CBTS would be reduced significantly. In other words, this Project will alleviate the existing odour problems in the vicinity of CBTS to a large extent by implementing the proposed enhancement measures. To ascertain the effectiveness of the Enhancement Package over time, and to monitor any on-going odour impacts at the ASRs, regular monitoring of odour impacts in the first five years upon commissioning of the Project is proposed during the operational phase.

2.2 Air Quality Parameters

Construction Phase

2.2.1 Monitoring and audit of the TSP levels shall be carried out by the ET to ensure that any deteriorating air quality could be readily detected and timely action taken to rectify the situation.

2.2.2 One-hour and 24-hour TSP levels should be measured to indicate the impacts of construction dust on air quality. The 24-hour TSP levels shall be measured by following the standard high volume sampling method as set out in the Title 40 of the Code of Federal Regulations, Chapter 1 (Part 50), Appendix B.

2.2.3 All relevant data including temperature, pressure, weather conditions, elapsed-time meter reading for the start and stop of the sampler, identification and weight of the filter paper, and any other local atmospheric factors affecting or affected by site conditions, etc., shall be recorded down in detail. A sample data sheet is shown in Appendix B1.

2.2.1 The locations of air sensitive receivers (ASRs) within and adjacent to the Project work site are shown in Figure 2.1.

Operation Phase

2.2.2 Odour patrol should be conducted by independent trained personnel / competent persons patrolling and sniffing at the planned ASR to indicate the operational odour impacts.

2.2.3 During the operation phase, the operator for the proposed CWB tunnel, HyD, will conduct air quality monitoring of NO₂ and RSP concentrations in a regular interval to indicate the operation performance of the EVB ventilation shaft. The methodology, equipment, monitoring locations, an criteria for the monitoring should be formulated in the detailed design stage subject to agreement between EPD and HyD.

2.3 Monitoring Equipment

Construction Phase

2.3.1 High volume samplers (HVSs) in compliance with the following specifications shall be used for carrying out the 1-hour and 24-hour TSP monitoring:

a) 0.6 - 1.7 m³per minute adjustable flow range;

b) equipped with a timing / control device with +/- 5 minutes accuracy for 24 hours operation;

c) installed with elapsed-time meter with +/- 2 minutes accuracy for 24 hours operation;

d) capable of providing a minimum exposed area of 406 cm²;

e) flow control accuracy: +/- 2.5% deviation over 24-hour sampling period;

f) equipped with a shelter to protect the filter and sampler;

g) incorporated with an electronic mass flow rate controller or other equivalent devices;

h) equipped with a flow recorder for continuous monitoring;

i) provided with a peaked roof inlet;

j) incorporated with a manometer;

k) able to hold and seal the filter paper to the sampler housing at horizontal position;

l) easily changeable filter; and

m) capable of operating continuously for a 24-hour period.

2.3.2 The ET is responsible for provision of the monitoring equipment. They shall ensure that sufficient number of HVSs with an appropriate calibration kit are available for carrying out the baseline monitoring, regular impact monitoring and ad hoc monitoring. The HVSs shall be equipped with an electronic mass flow controller and be calibrated against a traceable standard at regular intervals. All the equipment, calibration kit, filter papers, etc., shall be clearly labelled.

2.3.3 Initial calibration of dust monitoring equipment shall be conducted upon installation and thereafter at bi-monthly intervals. The transfer standard shall be traceable to the internationally recognised primary standard and be calibrated annually. The concern parties such as IC(E) shall properly document the calibration data for future reference. All the data should be converted into standard temperature and pressure condition.

2.3.4 The flow-rate of the sampler before and after the sampling exercise with the filter in position shall be verified to be constant and be recorded in the data sheet as mentioned in Appendix B1.

2.3.5 If the ET proposes to use a direct reading dust meter to measure 1-hour TSP levels, he shall submit sufficient information to the IC(E) to prove that the instrument is capable of achieving a comparable result to the HVS. The instrument should also be calibrated regularly, and the 1-hour sampling shall be determined periodically by the HVS to check the validity and accuracy of the results measured by direct reading method.

2.3.6 Wind data monitoring equipment shall also be provided and set up set up for logging wind speed and wind direction near the dust monitoring locations. The equipment installation location shall be proposed by the ET and agreed with the IC(E). For installation and operation of wind data monitoring equipment, the following points shall be observed:

a) The wind sensors should be installed 10 m above ground so that they are clear of obstructions or turbulence caused by buildings.

b) The wind data should be captured by a data logger. The data shall be downloaded for analysis at least once a month.

c) The wind data monitoring equipment should be re-calibrated at least once every six months.

d) Wind direction should be divided into 16 sectors of 22.5 degrees each.

2.3.7 In exceptional situations, the ET may propose alternative methods to obtain representative wind data upon approval from the ER and agreement from the IC(E).

2.4 Laboratory Measurement / Analysis

Construction Phase

2.4.1 A clean laboratory with constant temperature and humidity control, and equipped with necessary measuring and conditioning instruments to handle the dust samples collected, shall be available for sample analysis, and equipment calibration and maintenance. The laboratory should be HOKLAS accredited.

2.4.2 If a site laboratory is set up or a non-HOKLAS accredited laboratory is hired for carrying out the laboratory analysis, the laboratory equipment shall be approved by the ER and the measurement procedures shall be witnessed by the IC(E). Any measurement performed by the laboratory shall be demonstrated to the satisfaction of the ER and IC(E). IC(E) shall regularly audit to the measurement performed by the laboratory to ensure the accuracy of measurement results. The ET Leader shall provide the ER with one copy of the Title 40 of the Code of Federal Regulations, Chapter 1 (Part 50), Appendix B for his reference.

2.4.3 Filter paper of size 8" x 10" shall be labelled before sampling. It shall be a clean filter paper with no pinholes, and shall be conditioned in a humidity-controlled chamber for over 24-hours and be pre-weighed before use for the sampling.

2.4.4 After sampling, the filter paper loaded with dust shall be kept in a clean and tightly sealed plastic bag. The filter paper shall then be returned to the laboratory for reconditioning in the humidity-controlled chamber followed by accurate weighing by an electronic balance with readout down to 0.1 mg. The balance shall be regularly calibrated against a traceable standard.

2.4.5 All the collected samples shall be kept in a good condition for 6 months before disposal.

2.5 Monitoring Locations

2.5.1 The dust monitoring stations and odour monitoring route for construction and operation phases are shown in Figures 2.2 and 2.3 respectively.

2.6 Baseline Monitoring

Construction Phase

2.6.1 Baseline monitoring shall be carried out at all of the designated monitoring locations for at least 14 consecutive days prior to the commissioning of the construction works to obtain daily 24-hour TSP samples. The selected baseline monitoring stations should reflect baseline conditions at the impact stations. One-hour sampling should also be done at least 3 times per day while the highest dust impact is expected.

2.6.2 During the baseline monitoring, there should not be any construction or dust generation activities in the vicinity of the monitoring stations. Before commencing baseline monitoring, the ET shall inform the IC(E) of the baseline monitoring programme such that the ER can conduct on-site audit to ensure accuracy of the baseline monitoring results.

2.6.3 In case the baseline monitoring cannot be carried out at the designated monitoring locations during the baseline monitoring period, the ET Leader shall carry out the monitoring at alternative locations that can effectively represent the baseline conditions at the impact monitoring locations. The alternative baseline monitoring locations shall be approved by the ER and agreed with the IC(E).

2.6.4 In exceptional cases, when insufficient baseline monitoring data or questionable results are obtained, the ET shall liaise with the IC(E) and EPD to agree on an appropriate set of data to be used as a baseline reference and submit to ER for approval.

2.6.5 Ambient conditions may vary seasonally and shall be reviewed once every three months. When the ambient conditions have changed and a repeat of the baseline monitoring is required to be carried out for obtaining the updated baseline levels, the monitoring should be at times when the Contractor's activities are not generating dust, at least in the proximity of the monitoring stations. Should change in ambient conditions be determined, the baseline levels and, in turn, the air quality criteria, should be revised. The revised baseline levels and air quality criteria should be agreed with the IC(E) and EPD.

Operation Phase

2.6.6 One year prior to the commissioning of the Project, a programme to monitor odour intensity / odour patrol along the monitoring route as shown in Figure 2.3 shall be undertaken.

2.6.7 The measured results at ASR will serve as the baseline data set prior to the commissioning of the Project. These will be compared with the results obtained during the impact monitoring stage.

2.6.8 In addition, the following information shall be obtained:

· Meteorological conditions from the nearest Hong Kong Observatory’s Weather Station (including temperature, wind speed, relative humidity) during the monitoring;

· Whether any abnormal operations were being carried out at the CBTS during the monitoring.

2.6.9 The baseline monitoring events shall be carried out every three months at the same location within the year before the Project commissioned.

2.7 Impact Monitoring of Construction Air Quality Impact

2.7.1 The ET shall carry out impact monitoring during the course of the Works. For regular impact monitoring, the sampling frequency of at least once in every six-days, shall be strictly observed at all the monitoring stations for 24-hour TSP monitoring. For 1-hour TSP monitoring, the sampling frequency of at least three times in every six-days should be undertaken when the highest dust impact occurs. Before commencing baseline monitoring, the ET shall inform the IC(E) of the impact monitoring programme such that the IC(E) can conduct on-site audit to ensure accuracy of the impact monitoring results.

2.7.2 The specific time to start and stop the 24-hour TSP monitoring shall be clearly defined for each location and be strictly followed by the operator.

2.7.3 In case of non-compliance with the air quality criteria, more frequent monitoring, as specified in the Action Plan in the following section, shall be conducted within 24 hours after the result is obtained. This additional monitoring shall be continued until the excessive dust emission or the deterioration in air quality is rectified.

2.8 Impact Monitoring of Operation Air Quality Impact

2.8.1 Odour monitoring in the form of odour patrol shall be conducted by the CEDD[1] at the proposed monitoring route as shown in Figure 2.3.

2.8.2 The odour monitoring programme shall be conducted for a period of five years during the operation of the Project. The monitoring events shall be carried out during daytime and during the period of July to September on a monthly basis in order to capture the likely worst case scenario of a year.

2.8.3 The monitoring shall not be conducted on rainy days. Hourly meteorological conditions (temperature, wind speed & direction, humidity) shall be recorded throughout the monitoring period.

Odour Patrol

2.8.4 Odour patrol shall be conducted by independent trained personnel / competent persons patrolling and sniffing around the shore and breakwaters as shown in Figure 2.3 to detect any odour at the concerned hours.

2.8.5 The independent trained personnel / competent persons shall:

· have their individual odour threshold of n-butanol in nitrogen gas in the range of 20 to
80 ppb/v required by the European Standard Method (EN 13725).

· be at least 16 years of age and willing and able to follow instructions.

· be free from any respiratory illnesses.

· be engaged for a sufficient period to build up and monitor/detect at several monitoring location;

· not be allowed to smoke, eat, drink (except water) or use chewing gum or sweets 30 min before and during odour intensity analysis;

· take great care not to cause any interference with their own perception or that of others by lack of personal hygiene or the use of perfumes, deodorants, body lotions or cosmetics;

· not communicate with each other about the results of their choices.

2.8.6 At least three independent trained personnel / competent persons shall be selected to form a patrol team to conduct the odour intensity analysis, who should participated in a set of screening tests.

2.8.7 Subject to the prevailing weather forecast condition, odour patrol shall be conducted by independent trained personnel / competent persons at the downwind locations. During the patrol, the sequence should start from less odorous locations to stronger odorous locations.

2.8.8 The independent trained personnel / competent persons shall use their nose (olfactory sensors) to sniff odours at different locations. The main odour emission sources and the areas to be affected by the odour nuisance shall be identified.

2.8.9 The perceived odour intensity is to be divided into 5 levels which are ranked in the descending order as follows:

· 0 - Not detected. No odour perceived or an odour so weak that it can not be easily characterised or described;

· 1 - Slight Identifiable odour, and slight chance to have odour nuisance;

· 2 - Moderate Identifiable odour, and moderate chance to have odour nuisance;

· 3 - Strong Identifiable, likely to have odour nuisance;

· 4 - Extreme Severe odour, and unacceptable odour level.

2.8.10 The independent trained personnel / competent persons shall record the findings including odour intensity, odour nature and possible odour sources, and also the local wind speed and direction at each location. In addition, some relevant meteorological data such as daily average temperature, and daily average humidity, on that surveyed day shall be obtained from the Hong Kong Observatory Station for reference.

2.9 Environmental Quality Performance Limits

2.9.1 The baseline monitoring results form the basis for determining the air quality criteria for the impact monitoring. The ET shall compare the impact monitoring results with air quality criteria set up for 24-hour TSP and 1-hour TSP and odour criteria. Table 2.3 shows the air quality criteria, namely Action and Limit levels to be used.

Table 2.3 Action / Limit Levels for Air Quality

Parameters	Action	Limit
24-hour TSP Level in g m^-3	For baseline level £ 200 g m^-3, Action level = (baseline level * 1.3 + Limit level)/2; For baseline level > 200 g m^-3 Action level = Limit level	260 g m^-3
1-hour TSP Level in g m^-3	For baseline level £ 384 g m^-3, Action level = (baseline level * 1.3 + Limit level)/2; For baseline level > 384 g m^-3, Action level = Limit level	500 g m^-3
Odour Nuisance (from odour intensity analysis or odour patrol)	· When two documented complaint are received; or · Odour Intensity of 2 is measured from odour intensity analysis.	· Five or more consecutive genuine documented complaints within a week; or · Odour Intensity of 3 or above is measured from odour intensity analysis.

2.10 Event and Action Plan

2.10.1 Should non-compliance of the air quality criteria occur, actions in accordance with the Action Plan in Table 2.4 and 2.5 shall be carried out.

Table 2.4 Event / Action Plan for Construction Air Quality

EVENT	ACTION
ACTION LEVEL
1. Exceedance for one sample	1. Identify source, investigate the causes of exceedance and propose remedial measures; 2. Inform IC(E) and ER; 3. Repeat measurement to confirm finding; 4. Increase monitoring frequency to daily. (The above actions should be taken within 2 working days after the exceedance is identified)	1. Check monitoring data submitted by ET; 2. Check Contractor’s working method. (The above actions should be taken within 2 working days after the exceedance is identified)	1. Notify Contractor. (The above actions should be taken within 2 working days after the exceedance is identified)	1. Rectify any unacceptable practice; 2. Amend working methods if appropriate. (The above actions should be taken within 2 working days after the exceedance is identified)
2. Exceedance for two or more consecutive samples	1. Identify source; 2. Inform IC(E) and ER; 3. Advise the ER on the effectiveness of the proposed remedial measures; 4. Repeat measurements to confirm findings; 5. Increase monitoring frequency to daily; 6. Discuss with IC(E) and Contractor on remedial actions required; 7. If exceedance continues, arrange meeting with IC(E) and ER; 8. If exceedance stops, cease additional monitoring. (The above actions should be taken within 2 working days after the exceedance is identified)	1. Check monitoring data submitted by ET; 2. Check Contractor’s working method; 3. Discuss with ET and Contractor on possible remedial measures; 4. Advise the ET on the effectiveness of the proposed remedial measures; 5. Supervise Implementation of remedial measures. (The above actions should be taken within 2 working days after the exceedance is identified)	1. Confirm receipt of notification of failure in writing; 2. Notify Contractor; 3. Ensure remedial measures properly implemented. (The above actions should be taken within 2 working days after the exceedance is identified)	1. Submit proposals for remedial to ER within 3 working days of notification; 2. Implement the agreed proposals; 3. Amend proposal if appropriate. (The above actions should be taken within 2 working days after the exceedance is identified)
LIMIT LEVEL
1. Exceedance for one sample	1. Identify source, investigate the causes of exceedance and propose remedial measures; 2. Inform ER, Contractor and EPD; 3. Repeat measurement to confirm finding; 4. Increase monitoring frequency to daily; 5. Assess effectiveness of Contractor’s remedial actions and keep IC(E), EPD and ER informed of the results. (The above actions should be taken within 2 working days after the exceedance is identified)	1. Check monitoring data submitted by ET; 2. Check Contractor’s working method; 3. Discuss with ET and Contractor on possible remedial measures; 4. Advise the ER on the effectiveness of the proposed remedial measures; 5. Supervise implementation of remedial measures. (The above actions should be taken within 2 working days after the exceedance is identified)	1. Confirm receipt of notification of failure in writing; 2. Notify Contractor; 3. Ensure remedial measures properly implemented. (The above actions should be taken within 2 working days after the exceedance is identified)	1. Take immediate action to avoid further exceedance; 2. Submit proposals for remedial actions to IC(E) within 3 working days of notification; 3. Implement the agreed proposals; 4. Amend proposal if appropriate. (The above actions should be taken within 2 working days after the exceedance is identified)
2. Exceedance for two or more consecutive samples	1. Notify IC(E), ER, Contractor and EPD; 2. Identify source; 3. Repeat measurement to confirm findings; 4. Increase monitoring frequency to daily; 5. Carry out analysis of Contractor’s working procedures to determine possible mitigation to be implemented; 6. Arrange meeting with IC(E) and ER to discuss the remedial actions to be taken; 7. Assess effectiveness of Contractor’s remedial actions and keep IC(E), EPD and ER informed of the results; 8. If exceedance stops, cease additional monitoring. (The above actions should be taken within 2 working days after the exceedance is identified)	1. Discuss amongst ER, ET, and Contractor on the potential remedial actions; 2. Review Contractor’s remedial actions whenever necessary to assure their effectiveness and advise the ER accordingly; 3. Supervise the implementation of remedial measures.	1. Confirm receipt of notification of failure in writing; 2. Notify Contractor; 3. In consolidation with the IC(E), agree with the Contractor on the remedial measures to be implemented; 4. Ensure remedial measures properly implemented; 5. If exceedance continues, consider what portion of the work is responsible and instruct the Contractor to stop that portion of work until the exceedance is abated. (The above actions should be taken within 2 working days after the exceedance is identified)	1. Take immediate action to avoid further exceedance; 2. Submit proposals for remedial actions to IC(E) within 3 working days of notification; 3. Implement the agreed proposals; 4. Resubmit proposals if problem still not under control; 5. Stop the relevant portion of works as determined by the ER until the exceedance is abated. (The above actions should be taken within 2 working days after the exceedance is identified)

EVENT

ACTION

IC(E)

CONTRACTOR

ACTION LEVEL

1. Exceedance for one sample

1. Identify source, investigate the causes of exceedance and propose remedial measures;

2. Inform IC(E) and ER;

3. Repeat measurement to confirm finding;

4. Increase monitoring frequency to daily.

(The above actions should be taken within 2 working days after the exceedance is identified)

1. Check monitoring data submitted by ET;

2. Check Contractor’s working method.

(The above actions should be taken within 2 working days after the exceedance is identified)

1. Notify Contractor.

(The above actions should be taken within 2 working days after the exceedance is identified)

1. Rectify any unacceptable practice;

2. Amend working methods if appropriate.

(The above actions should be taken within 2 working days after the exceedance is identified)

2. Exceedance for two or more consecutive samples

1. Identify source;

2. Inform IC(E) and ER;

3. Advise the ER on the effectiveness of the proposed remedial measures;

4. Repeat measurements to confirm findings;

5. Increase monitoring frequency to daily;

6. Discuss with IC(E) and Contractor on remedial actions required;

7. If exceedance continues, arrange meeting with IC(E) and ER;

8. If exceedance stops, cease additional monitoring.

(The above actions should be taken within 2 working days after the exceedance is identified)

1. Check monitoring data submitted by ET;

2. Check Contractor’s working method;

3. Discuss with ET and Contractor on possible remedial measures;

4. Advise the ET on the effectiveness of the proposed remedial measures;

5. Supervise Implementation of remedial measures.

(The above actions should be taken within 2 working days after the exceedance is identified)

1. Confirm receipt of notification of failure in writing;

2. Notify Contractor;

3. Ensure remedial measures properly implemented.

(The above actions should be taken within 2 working days after the exceedance is identified)

1. Submit proposals for remedial to ER within 3 working days of notification;

2. Implement the agreed proposals;

3. Amend proposal if appropriate.

(The above actions should be taken within 2 working days after the exceedance is identified)

LIMIT LEVEL

1. Exceedance for one sample

1. Identify source, investigate the causes of exceedance and propose remedial measures;

2. Inform ER, Contractor and EPD;

3. Repeat measurement to confirm finding;

4. Increase monitoring frequency to daily;

5. Assess effectiveness of Contractor’s remedial actions and keep IC(E), EPD and ER informed of the results.

(The above actions should be taken within 2 working days after the exceedance is identified)

1. Check monitoring data submitted by ET;

2. Check Contractor’s working method;

3. Discuss with ET and Contractor on possible remedial measures;

4. Advise the ER on the effectiveness of the proposed remedial measures;

5. Supervise implementation of remedial measures.

(The above actions should be taken within 2 working days after the exceedance is identified)

1. Confirm receipt of notification of failure in writing;

2. Notify Contractor;

3. Ensure remedial measures properly implemented.

(The above actions should be taken within 2 working days after the exceedance is identified)

1. Take immediate action to avoid further exceedance;

2. Submit proposals for remedial actions to IC(E) within 3 working days of notification;

3. Implement the agreed proposals;

4. Amend proposal if appropriate.

(The above actions should be taken within 2 working days after the exceedance is identified)

2. Exceedance for two or more consecutive samples

1. Notify IC(E), ER, Contractor and EPD;

2. Identify source;

3. Repeat measurement to confirm findings;

4. Increase monitoring frequency to daily;

5. Carry out analysis of Contractor’s working procedures to determine possible mitigation to be implemented;

6. Arrange meeting with IC(E) and ER to discuss the remedial actions to be taken;

7. Assess effectiveness of Contractor’s remedial actions and keep IC(E), EPD and ER informed of the results;

8. If exceedance stops, cease additional monitoring.

(The above actions should be taken within 2 working days after the exceedance is identified)

1. Discuss amongst ER, ET, and Contractor on the potential remedial actions;

2. Review Contractor’s remedial actions whenever necessary to assure their effectiveness and advise the ER accordingly;

3. Supervise the implementation of remedial measures.

1. Confirm receipt of notification of failure in writing;

2. Notify Contractor;

3. In consolidation with the IC(E), agree with the Contractor on the remedial measures to be implemented;

4. Ensure remedial measures properly implemented;

5. If exceedance continues, consider what portion of the work is responsible and instruct the Contractor to stop that portion of work until the exceedance is abated.

(The above actions should be taken within 2 working days after the exceedance is identified)

1. Take immediate action to avoid further exceedance;

2. Submit proposals for remedial actions to IC(E) within 3 working days of notification;

3. Implement the agreed proposals;

4. Resubmit proposals if problem still not under control;

5. Stop the relevant portion of works as determined by the ER until the exceedance is abated.

(The above actions should be taken within 2 working days after the exceedance is identified)

Table 2.5 Event/Action Plan for Operation Air Quality Monitoring

EVENT	ACTION
EVENT	Person-in-charge of Odour Monitoring	CEDD[2]
ACTION LEVEL
Exceedance of action level	1. Identify source/reason of exceedance; 2. Repeat odour patrol to confirm finding.	1. Carry out investigation to identify the source/reason of exceedance. Investigation shall be completed within 2 week; 2. Rectify any unacceptable practice; 3. Implement more mitigation measures if necessary; 4. Inform EPD or MD if exceedance is considered to be caused by expedient connections or floating debris.
LIMIT LEVEL
Exceedance of Limit level	1. Identify source / reason of exceedance; 2. Repeat odour patrol to confirm findings; 3. Increase odour patrol frequency to bi-weekly; 4. If exceedance stops, cease additional odour patrol.	1. Carry out investigation to identify the source/reason of exceedance. Investigation shall be completed within 2 week; 2. Rectify any unacceptable practice; 3. Formulate remedial actions; 4. Ensure remedial actions properly implemented; 5. If exceedance continues, consider what more/enhanced mitigation measures shall be implemented; 6. Inform EPD or MD if exceedance is considered to be caused by expedient connections or floating debris.

[1] CEDD will identify an implementation agent.

[2] CEDD will identify an implementation agent.

2 AIR QUALITY

2.2.1 Monitoring and audit of the TSP levels shall be carried out by the ET to ensure that any deteriorating air quality could be readily detected and timely action taken to rectify the situation.

2.2.1 The locations of air sensitive receivers (ASRs) within and adjacent to the Project work site are shown in Figure 2.1.

2.2.2 Odour patrol should be conducted by independent trained personnel / competent persons patrolling and sniffing at the planned ASR to indicate the operational odour impacts.

2.3.1 High volume samplers (HVSs) in compliance with the following specifications shall be used for carrying out the 1-hour and 24-hour TSP monitoring:

2.3.4 The flow-rate of the sampler before and after the sampling exercise with the filter in position shall be verified to be constant and be recorded in the data sheet as mentioned in Appendix B1.

2.3.7 In exceptional situations, the ET may propose alternative methods to obtain representative wind data upon approval from the ER and agreement from the IC(E).

2.4.3 Filter paper of size 8" x 10" shall be labelled before sampling. It shall be a clean filter paper with no pinholes, and shall be conditioned in a humidity-controlled chamber for over 24-hours and be pre-weighed before use for the sampling.

2.4.5 All the collected samples shall be kept in a good condition for 6 months before disposal.

2.5.1 The dust monitoring stations and odour monitoring route for construction and operation phases are shown in Figures 2.2 and 2.3 respectively.

2.6.4 In exceptional cases, when insufficient baseline monitoring data or questionable results are obtained, the ET shall liaise with the IC(E) and EPD to agree on an appropriate set of data to be used as a baseline reference and submit to ER for approval.

2.6.6 One year prior to the commissioning of the Project, a programme to monitor odour intensity / odour patrol along the monitoring route as shown in Figure 2.3 shall be undertaken.

2.6.7 The measured results at ASR will serve as the baseline data set prior to the commissioning of the Project. These will be compared with the results obtained during the impact monitoring stage.

2.6.8 In addition, the following information shall be obtained:

2.6.9 The baseline monitoring events shall be carried out every three months at the same location within the year before the Project commissioned.

2.7 Impact Monitoring of Construction Air Quality Impact

2.7.2 The specific time to start and stop the 24-hour TSP monitoring shall be clearly defined for each location and be strictly followed by the operator.

2.8.1 Odour monitoring in the form of odour patrol shall be conducted by the CEDD[1] at the proposed monitoring route as shown in Figure 2.3.

2.8.3 The monitoring shall not be conducted on rainy days. Hourly meteorological conditions (temperature, wind speed & direction, humidity) shall be recorded throughout the monitoring period.

2.8.4 Odour patrol shall be conducted by independent trained personnel / competent persons patrolling and sniffing around the shore and breakwaters as shown in Figure 2.3 to detect any odour at the concerned hours.

2.8.5 The independent trained personnel / competent persons shall:

· have their individual odour threshold of n-butanol in nitrogen gas in the range of 20 to 80 ppb/v required by the European Standard Method (EN 13725).

· be at least 16 years of age and willing and able to follow instructions.

· be free from any respiratory illnesses.

· be engaged for a sufficient period to build up and monitor/detect at several monitoring location;

· not be allowed to smoke, eat, drink (except water) or use chewing gum or sweets 30 min before and during odour intensity analysis;

· take great care not to cause any interference with their own perception or that of others by lack of personal hygiene or the use of perfumes, deodorants, body lotions or cosmetics;

· not communicate with each other about the results of their choices.

2.8.6 At least three independent trained personnel / competent persons shall be selected to form a patrol team to conduct the odour intensity analysis, who should participated in a set of screening tests.

2.8.7 Subject to the prevailing weather forecast condition, odour patrol shall be conducted by independent trained personnel / competent persons at the downwind locations. During the patrol, the sequence should start from less odorous locations to stronger odorous locations.

2.8.8 The independent trained personnel / competent persons shall use their nose (olfactory sensors) to sniff odours at different locations. The main odour emission sources and the areas to be affected by the odour nuisance shall be identified.

2.8.9 The perceived odour intensity is to be divided into 5 levels which are ranked in the descending order as follows:

· 0 - Not detected. No odour perceived or an odour so weak that it can not be easily characterised or described;

· 1 - Slight Identifiable odour, and slight chance to have odour nuisance;

· 2 - Moderate Identifiable odour, and moderate chance to have odour nuisance;

· 3 - Strong Identifiable, likely to have odour nuisance;

· 4 - Extreme Severe odour, and unacceptable odour level.

2.9 Environmental Quality Performance Limits

2.10.1 Should non-compliance of the air quality criteria occur, actions in accordance with the Action Plan in Table 2.4 and 2.5 shall be carried out.

2.11.1 As described in the EIA Report, the ASRs from Central to Causeway Bay would comply with AQO and EIAO-TM criteria during construction phase of each Designated Projects. The mitigation measures proposed for each Designated Projects are presented in Appendices D to I.

2.11.2 Existing odour pollution sources would have potential odour impact on the planned ASR. The following mitigation measures are recommended to be implemented to reduce the odour impact in future.

2.11.3 The implementation schedule for the mitigation measures during construction phase and operation phase is presented in Appendix A.

· have their individual odour threshold of n-butanol in nitrogen gas in the range of 20 to
80 ppb/v required by the European Standard Method (EN 13725).