2.1.1.1 This section presents the requirements, methodology, equipment, monitoring locations, criteria and protocols for the monitoring and audit of air quality impacts during the construction and operational phases of the Project.

2.1.1.2 The objectives of the air quality monitoring shall be:

Ÿ to identify the extent of construction dust and operational odour impacts on sensitive receivers;

Ÿ to determine the effectiveness of mitigation measures to control fugitive dust emission from activities during construction phase and odour control measures during operational phase;

Ÿ to audit the compliance of the Contractor with regard to dust control, contract conditions and the relevant dust impact criteria;

Ÿ to recommend further mitigation measures if found to be necessary; and

Ÿ to comply with Action and Limit (A/L) Levels for air quality as defined in this Manual.

2.2 Air Quality Parameters

2.2.1.1 The criteria against which ambient air quality monitoring shall be assessed are:

Ÿ The Hong Kong Air Quality Objectives (AQOs) for TSP, 24-hour TSP levels of 260 mg m^-3;

Ÿ The statutory 1-hour TSP limit of 500 mg m^-3; and

Ÿ 5 odour units based on averaging time of 5 seconds

2.2.1.2 These levels are not to be exceeded at Air Sensitive Receivers (ASRs).

2.2.1.3 The locations of air sensitive receivers (ASRs) within and adjacent to the project area are shown in Figure 2.1.

2.3 Monitoring Requirement and Equipment

Construction Phase

2.3.1.1 1-hour and 24-hour TSP levels shall be measured to indicate the impacts of construction dust on air quality. The TSP levels shall be measured by following the standard method as set out in High Volume Method for Total Suspended Particulates, Part 50 Chapter 1 Appendix B, Title 40 of the Code of Federal Regulations of the USEPA.

2.3.1.2 Dust laden air shall be drawn through a high volume sampler (HVS) fitted with a conditioned, pre-weighed filter paper, at a controlled rate. After sampling for 24-hours, the filter paper with retained particles is collected and returned to the laboratory for drying in a desiccator followed by accurate weighing. 1-hour and 24-hour average TSP levels are calculated from the ratio of the mass of particulates retained on the filter paper to the total volume of air sampled.

2.3.1.3 All relevant data including temperature, pressure, weather conditions, elapsed-time meter reading for the start and stop of sampler, identification and weight of the filter paper, and other special phenomena and work progress of the concerned site, etc, shall be recorded in detail. A sample data sheet is shown in Appendix B.

2.3.1.4 HVS in compliance with the following specifications shall be used for carrying out the 1-hour and 24-hour monitoring:

· 0.6 - 1.7 m³ per minute (20 - 60 standard cubic feet per minute) adjustable flow range;

· equipped with a timing / control device with ± 5 minutes accuracy for 24 hours operation;

· installed with elapsed-time meter with ± 2 minutes accuracy for 24 hours operation;

· capable of providing a minimum exposed area of 406 cm² (63 in²);

· flow control accuracy: ± 2.5% deviation over 24-hour sampling period;

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

· equipped with a flow recorder for continuous monitoring;

· provided with a peaked roof inlet;

· incorporated with a manometer;

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

· easy to change the filter;

· capable of operating continuously for 24-hour period.

2.3.1.5 The ET shall be responsible for the provision of the monitoring equipment. He shall ensure that sufficient number of HVSs with appropriate calibration kit is available for carrying out the baseline, regular impacts 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, in accordance with requirements stated in the manufacturers operating manual and as described below. All the equipment, calibration kit, filter papers, etc, shall be clearly labelled.

2.3.1.6 The flow rate of each HVS with mass flow controller shall be calibrated using an orifice calibrator. Initial calibration of the dust monitoring equipment shall be conducted upon installation and prior to commissioning. One point flow rate calibration shall be carried out every two months. Five-point calibration shall be carried out every six months. The calibration data shall be properly documented for future reference by the concerned parties such as the IEC. All the data shall be converted into standard temperature and pressure condition.

2.3.1.7 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 on the data sheet as mentioned in Appendix B.

Operational Phase

2.3.1.8 An Odour Complaint Registration System is recommended to be included in the EM&A Programme. The system is meaningful to assess whether the ASRs experience odour nuisance as a result of emissions from the upgraded PPSTW. Currently, odour complaint falls into the category of “complaints relating to policy, standard of service and management matters on drainage works” under the DSD Administration Circular No. 8/2001. This current practice shall be continued during the operational phase of the Project.

Odour Patrol

2.3.1.9 Odour patrol should be conducted by independent trained personnel / competent persons patrolling and sniffing at the PPSTW boundary and the ASRs in the vicinity of the PPSTW to indicate the operational odour impacts. The odour patrol member should participated in a set of screening tests using a certified n-butanol gas with their individual thresholds (n-butanol) complied with the requirement of European Standard Method (EN13725) in the range of 20 to 80 ppb. They should also be free from any respiratory diseases and do not normally work at or live in the area in the vicinity of PPSTW.

Odour Complaint Registration

2.3.1.10 In the event when an odour complaint is received at the upgraded PPSTW, the Contractor and Plant Operator shall liaise with the complainant together with the SOR and a Complaint Registration Form shall be completed. The Complaint Registration Form is to record detailed information regarding the odour complaint and hence, facilitates efficient investigation work. The registration form shall contain, but not be limited to the following information:

· Location of where the odour nuisance occurred, including whether the odour was experienced indoors or outdoors;

· Date and time of the complaint and the nuisance event;

· Description of the complaint, i.e. the type and characteristics of the odour; and an indication of the odour strength (highly offensive / offensive / slightly offensive / just continuously detectable /intermittently detectable); and

· Name and contact information of the complainant.

2.3.1.11 This information shall be obtained by the Contractor when the complaint is received. The Complaint Registration Form is shown in Appendix C for reference.

2.3.1.12 In addition, the following information shall be obtained:

·Meteorological conditions from the Hong Kong Observatory’s Tuen Mun Weather Station (including temperature, wind speed, relative humidity) at the time of the complaint; and

·Whether any abnormal operations were being carried out at the upgraded PPSTW at the time the nuisance occurred.

2.3.1.13 The Odour Complaint Register shall be kept at the upgraded PPSTW.

2.4 Monitoring Locations

Construction Phase

2.4.1.1 Two worst affected locations have been identified for TSP dust monitoring as shown in Table 2.1 and illustrated in Figure 2.2. Prior to the commencement of the EM&A programme, the proposed air quality monitoring stations shall be reviewed with the SOR, IEC, DSD and EPD.

Table 2.1 Air Monitoring Stations during Construction Phase

Identification No.	Air Monitoring Location
AM1	Tuen Mun EMSD Servicing Vehicle Station
AM2	River Trade Terminal Office

2.4.1.2 When alternative monitoring locations are proposed, the monitoring locations shall be chosen based on the following criteria:

Ÿ monitoring at sensitive receivers close to the major site activities which are likely to have air quality impacts;

Ÿ monitoring at the air sensitive receivers as defined in the Technical Memorandum;

Ÿ assurance of minimal disturbance to the occupants during monitoring.

2.4.1.3 When positioning the HVS samplers, the following points shall be noted:

Ÿ a horizontal platform with appropriate support to secure the samples against gusty wind shall be provided;

Ÿ no two sampler shall be placed less than 2 m apart;

Ÿ the distance between the sampler and an obstacle, such as buildings, must be at least twice the height that the obstacle protrudes above the sampler;

Ÿ A minimum of 2 m separation from walls, parapets and penthouses is required for rooftops samplers;

Ÿ a minimum of 2 m separation from any supporting structure, measures horizontally is required;

Ÿ no furnace or incinerator flue is nearby;

Ÿ airflow around the sampler is unrestricted;

Ÿ the sampler is more than 20 m from the dripline;

Ÿ any wire fence and gate to protect the sampler, shall not cause any obstruction during monitoring;

Ÿ permission must be obtained to set up the samplers and to obtain access to the monitoring stations; and

Ÿ a secured supply of electricity is needed to operate the samplers.

Operational Phase

2.4.1.4 The odour patrol shall be conducted at the PPSTW boundary and the ASRs in the vicinity of the PPSTW including River Trade Terminal Office, Chu Kong Warehouse 1 & 2, Sawmill, Pillar Point Fire Station, Sunhing Hung Kai Tuen Mun Godown and Tuen Mun EMSD Servicing Vehicle Station.

2.5 Baseline Monitoring

1-hr & 24-hr TSP Monitoring (Construction Phase)

2.5.1.1 Baseline monitoring shall be carried out by the ET to determine the ambient 1-hour and 24‑hour TSP levels at the monitoring locations prior to the commencement of the construction works. During the baseline monitoring, there shall not be any construction or dust generating activities in the vicinity of the monitoring stations. TSP baseline monitoring shall be carried out for a continuous period of at least two weeks under typical weather conditions with the 24-hour and three 1-hour ambient measurements taken daily at each monitoring location. General meteorological conditions (wind speed, direction and precipitation) and notes regarding any significant adjacent dust producing sources shall also be recorded throughout the baseline monitoring period.

2.5.1.2 The baseline monitoring will provide data for the determination of the appropriate Action levels with the Limit levels set against statutory or otherwise agreed limits.

2.5.1.3 Baseline checking of ambient TSP levels shall be carried out every six months at each monitoring location, when no dusty works activities are in operation. If the ET considers that significant changes in the ambient conditions have arisen, a repeat of the baseline monitoring may be carried out to update the baseline levels and air quality criteria, after consultation and agreement with the SOR, the IEC, DSD and EPD.

Odour (Operational Phase)

Odour Patrol

2.5.1.4 One year prior to the commissioning of the upgraded PPSTW, a programme to monitor odour intensity / odour patrol along the PPSTW boundary and the ASRs in the vicinity of the PPSTW.

2.5.1.5 The monitored results at ASR will serve as the baseline data set prior to the commissioning of the upgraded PPSTW. These will be compared with the results obtained during the impact monitoring stage.

2.5.1.6 In addition, the following information shall be obtained:

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

Ÿ Whether any abnormal operations were being carried out at PPSTW during the monitoring.

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

2.6 Impact Monitoring for Construction Air Quality Impact

2.6.1.1 The ET Leader shall carry out impact monitoring during the course of the works. For regular impact monitoring, a 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 shall be undertaken when the highest dust impact occurs. The impact monitoring programme is summarised in Table 2.3.

Table 2.3 Impact Monitoring Programme (TSP)

Sampling duration	Frequency
1 hour	· 3 times every 6 days
24 hours	· Once every 6 days

2.6.1.2 Before commencing the baseline monitoring, the ET leader shall inform the IEC of the impact monitoring programme such that the IEC can conduct an on-site audit to ensure the accuracy of the impact monitoring results.

2.7 Impact Monitoring for Operation Air Quality Impact

Odour Patrol

2.7.1.1 The odour patrol shall be conducted for a period of one year during the operation of the upgraded PPSTW. The monitoring events shall be carried out during daytime and evening on a monthly basis in order to capture the likely worst case scenario of a year.

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

2.7.1.3 Odour patrol shall be conducted by two independent trained personnel / competent persons patrolling and sniffing along the PPSTW boundary and the ASRs in the vicinity of the PPSTW as shown in Figure 2.2 to detect any odour at the concerned hours.

2.7.1.4 The independent trained personnel / competent persons shall:

Ÿ 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).

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

Ÿ be free from any respiratory illnesses.

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

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

Ÿ 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;

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

2.7.1.5 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.

2.7.1.6 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.

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

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

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

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

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

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

2.7.1.8 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.

2.7.1.9 The operational phase monitoring programme (odour monitoring and odour patrol) is summarised in Table 2.4. The record sheet for odour patrol monitoring during operational phase is provided in Appendix B.

Table 2.4 Operational Phase Monitoring Programme (Odour)

Sampling duration

Frequency

Odour Patrol

· Once every month for the first year after operation of upgraded PPSTW.

· If the results of any month detected odour intensity at any ASR is higher than 1 due to operation of PPSTW, the odour patrol programme shall be extended until the odour intensity at the ASR in consecutive 2 months are below 1.

· If the results of any month detected odour intensity at any ASR is 2 or higher due to operation of PPSTW, the odour patrol frequency would be bi-weekly and the odour patrol programme shall be extended until the odour intensity at the ASR in consecutive 2 months are below 1.

2.8 Compliance Assessment

2.8.1.1 Action and Limit (A/L) levels that provide an appropriate framework for the interpretation of monitoring results have to be reviewed between ET, IEC, DSD, EPD and the SOR before commencement of the air quality monitoring. The air quality monitoring data shall be checked against the agreed A/L levels. Recommended A/L levels are listed in Table 2.5.

Table 2.5 Proposed Action and Limit Levels for Impact Monitoring

Parameter	Action Level ⁽¹⁾	Limit Level
TSP (24 hour average)	· BL £ 200 mg m^-3, AL = (BL * 1.3 + LL)/2 · BL > 200 mg m^-3, AL = LL	260 mg m^-3
TSP (1 hour average)	· BL £ 384 mg m^-3, AL = (BL * 1.3 + LL)/2 · BL > 384 mg m^-3, AL = LL	500 mg m^-3
Odour Nuisance (from odour intensity analysis or odour patrol)	· Odour Intensity of higher than 1 is measured from odour intensity analysis.	Odour Intensity of 2 or above is measured from odour intensity analysis.
Incidence of odour complaints	Any incidence of odour complaint received through the Odour Complaint Register	Two or more complaints through the Odour Complaint Register within three months

(1) BL = Baseline level, AL = Action level, LL = Limit level.

2.9 Event and Action Plan (EA P) for Air Quality

2.9.1.1 The EAP is based on the prescription of procedures and actions associated with the measurement of certain defined levels of air pollution recorded by the environmental monitoring process and the agreed A/L levels. In case TSP A/L level exceedances occur in the construction phase, the ET, the IEC, the SOR and the Contractor shall observe the relevant actions of the respective EAP listed in Table 2.6. For events of odour exceedance/complaint in the operational phase, the respective EAP listed in Table 2.7 should be observed.

Table 2.6 Event/Action Plan for Air Quality Monitoring (Construction Phase)

EVENT

ACTION

IEC

SOR

CONTRACTOR

ACTION LEVEL

1. Exceedance for one sample

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

2. Inform IEC and SOR;

3. Repeat measurement to confirm finding;

4. Increase monitoring frequency to daily.

1. Check monitoring data submitted by ET;

2. Check Contractor’s working method.

1. Notify Contractor and DSD.

1. Rectify any unacceptable practice;

2. Amend working methods if appropriate.

2. Exceedance for two or more consecutive samples

1. Identify source;

2. Inform IEC and SOR;

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

4. Repeat measurements to confirm findings;

5. Increase monitoring frequency to daily;

6. Discuss with IEC and Contractor on remedial actions required;

7. If exceedance continues, arrange meeting with IEC and SOR;

8. If exceedance stops, cease additional monitoring.

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.

1. Confirm receipt of notification of exceedance in writing;

2. Notify Contractor and DSD;

3. Ensure remedial measures properly implemented.

1. Submit proposals for remedial actions to IEC within three working days of notification;

2. Implement the agreed proposals;

3. Amend proposal if appropriate.

LIMIT LEVEL

1. Exceedance for one sample

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

2. Inform IEC, SOR, DSD and EPD;

3. Repeat measurement to confirm finding;

4. Increase monitoring frequency to daily;

5. Assess effectiveness of Contractor’s remedial actions and keep IEC, EPD, DSD and SOR informed of the results.

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 SOR on the effectiveness of the proposed remedial measures;

5. Supervise implementation of remedial measures.

1. Confirm receipt of notification of exceedance in writing;

2. Notify Contractor;

3. Ensure remedial measures properly implemented.

1. Take immediate action to avoid further exceedance;

2. Submit proposals for remedial actions to IEC within three working days of notification;

3. Implement the agreed proposals;

4. Amend proposal if appropriate.

2. Exceedance for two or more consecutive samples

1. Notify IEC, SOR, DSD 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 IEC and SOR to discuss the remedial actions to be taken;

7. Assess effectiveness of Contractor’s remedial actions and keep IEC, EPD, DSD and SOR informed of the results;

8. If exceedance stops, cease additional monitoring.

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

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

3. Supervise the implementation of remedial measures.

1. Confirm receipt of notification of exceedance in writing;

2. Notify Contractor;

3. In consolidation with the IEC, 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.

1. Take immediate action to avoid further exceedance;

2. Submit proposals for remedial actions to IEC within three 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 SOR until the exceedance is abated.

Table 2.7 Event/Action Plan for Air Quality Monitoring (Operation Phase)

EVENT

ACTION

IEC

SOR

CONTRACTOR

ACTION LEVEL

Exceedance of action level or receipt of any odour complaint

1. Identify source/reason of exceedance or odour complaints;

2. Notify the Contractor, IEC and SOR of exceedance

3. Carry out investigation to identify the source/reason of exceedance or complaints. Investigation shall be completed within 1 week;

4. Repeat odour patrol to confirm finding; and

5. If exceedance continues, notify the Contractor, IEC and SOR.

1. Check odour patrol results submitted by ET;

2. Check Contractor’s mitigation measures.

3. Supervise the implementation of remedial measures.

1. Confirm receipt of notification of exceedance in writing.

2. Notify DSD; and

3. Ensure remedial measures properly implemented.

1. Notify the SOR, ET, IEC and DSD when receipt of odour complaint;

2. Rectify any unacceptable practice; and formulate remedial actions; and

3. Correspond to the complainant within 10 days to inform the cause of the nuisance and action taken.

LIMIT LEVEL

Exceedance of Limit level or receipt of two or more complaints in 3 months

1. Identify source / reason of exceedance or odour complaints;

2. Notify the Contractor, IEC and SOR of exceedance

3. Carry out investigation to identify the source/reason of exceedance or complaints. Investigation shall be completed within 1 week;

4. Repeat odour patrols to confirm findings;

5. Increase odour patrol frequency to bi-weekly until no exceedance is detected at the ASR in the conservative 2 months and

6. If exceedance continues, notify the Contractor, IEC and SOR.

1. Check patrol results submitted by ET;

2. Discuss amongst SOR and Contractor on the potential remedial actions;

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

4. Supervise the implementation of remedial measures.

1. Confirm receipt of notification of exceedance in writing;

2. Notify DSD;

3. In consolidation with the IEC, agree with the Contractor on the remedial measures to be implemented; and

4. Ensure remedial measures properly implemented.

1. Notify the SOR, ET, IEC and DSD when receipt of odour complaints;

2. Modify or improve design as appropriate;

3. Submit proposals for remedial actions to IEC within three working days of notification of odour exceedance / complaint;

4. Implement the agreed proposals

5. Resubmit proposals if problem still not under control; and

6. Correspond to the complainant within 10 days to inform the cause of the nuisance and action taken.

2.10 Mitigation Measures

2.10.1.1 The EIA Report recommended air quality control and mitigation measures during the construction and operational phases of the Project. The implementation for the recommended mitigation measures is presented in Appendix A.