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Contents

1                 Introduction                                                                               

1.1              Project Scope                                                                            

1.2              Scope of the Enhanced TSP Monitoring Plan            

1.3              Works Programme                                                                   

2                 Enhanced TSP Monitoring                                                    

2.1              Introduction                                                                               

2.2              Monitoring Stations                                                               

2.3              Monitoring Parameter                                                          

2.4              Monitoring Equipment & Methodology                         

2.5              Laboratory Measurement and Analysis                     

2.6              Monitoring Period and Frequency                                  

2.7              Air Quality Compliance                                                         

3                 Results and Reporting                                                         

3.1              Baseline Monitoring                                                               

3.2              Impact Monitoring                                                                    

 

1                                   Introduction

According to the findings of the Northwest New Territories (NWNT) Traffic and Infrastructure Review conducted by the Transport Department, Tuen Mun Road, Ting Kau Bridge, Lantau Link and North Lantau Highway (NLH) will be operating beyond capacity after 2016 due to the increase in cross boundary traffic, developments in the NWNT, and possible developments in North Lantau, including the Airport developments, the Lantau Logistics Park (LLP) and the Hong Kong íV Zhuhai íV Macao Bridge (HZMB).  In order to cope with the anticipated traffic demand, two new road sections between NWNT and North Lantau íV Tuen Mun íV Chek Lap Kok Link (TM-CLKL) and Tuen Mun Western Bypass (TMWB) are proposed.

An Environmental Impact Assessment (EIA) of TM-CLKL (ížthe ProjectíĘ) was prepared in accordance with the EIA Study Brief (No. ESB-175/2007) and the Technical Memorandum of the Environmental Impact Assessment Process (EIAO-TM), which was submitted under the Environmental Impact Assessment Ordinance (EIAO) in August 2009.  Subsequent to the approval of the EIA (EIAO Register Number AEIAR-145/2009), an Environmental Permit (EP-354/2009) for TM-CLKL was granted by the Director of Environmental Protection (DEP) on 4 November 2009, and a variation to the EP (EP-354/2009A) was issued on 8 December 2010. 

The Supplementary Information on Construction Air Quality in Tuen Mun ([1]) (the Supplementary Information) submitted under Section 8.(1) of the EIAO for the Project stated that exceedances of the annual Total Suspended Particulates (TSP) criteria of 80µg/m3 were anticipated at seven existing Air Sensitive Receivers (ASRs) in the Pillar Point area during the construction stage of the Project.  As per Condition 2.4 of the EP of TM-CLKL, an enhanced monitoring plan on TSP level at Tuen Mun (ížthe Enhanced TSP Monitoring PlaníĘ) is required to be submitted to the DEP for approval at least 1 month before the commencement of construction of the Project.  The Enhanced TSP Monitoring Plan shall include the locations and frequency of monitoring and details of the measures to mitigate any upsurge of TSP level including increase the frequency of monitoring of TSP and stoppage of works. 

This Enhanced TSP Monitoring Plan has been prepared by ERM-Hong Kong, Limited (ERM) on behalf of Dragages-Bouygues Joint Venture (DBJV), the Contractor for Contract No. HY/2012/08, and presents the methodology for enhanced monitoring of TSP level at Tuen Mun to be undertaken in accordance with Condition 2.4 of the EP.

1.1                               Project Scope

The TM-CLKL comprises a dual 2-lane highway connecting the proposed Tuen Mun Western Bypass at the southern coast of Tuen Mun Area 40 and the Airport and Tung Chung (Figure 1.1).  The construction of TM-CLKL will be undertaken under the following five separate contracts:

íP           Contract I (appointed under Contract No. HY/2012/07) íV Southern Connection Viaduct Section;

íP           Contract II (appointed under Contract No. HY/2012/08) íV Northern Connection Sub-sea Tunnel Section (ížNorthern ConnectioníĘ);

íP           Contract III íV Northern Connection Toll Plaza and Associated Works (the ížtoll plazaíĘ);

íP           Contract IV íV Northern Connection Tunnel Buildings, Electrical and Mechanical Works (ížtunnel buildingsíĘ); and

íP           Contract V íV Northern Connection Traffic Control and Surveillance System (ížTCSSíĘ).

The scope of the above Contracts is indicated in Figures 1.2-6, respectively.

Under Contract No. HY/2012/08, DBJV is commissioned by the Highways Department (HyD) to undertake the design and construction of the Northern Connection Sub-sea Tunnel Section of TM-CLKL, including the northern landfall at Tuen Mun.     

Specifically, the scope of Contract No. HY/2012/08 includes:

íP          design and construction of sub-sea TBM tunnels (two tubes with cross passages) across the Urmston Road, connecting Tuen Mun Area 40 and HKBCF, of approximately 4 km in length with dual 2-lane carriageway;

íP          design and construction of cut-and-cover tunnels (two boxes with cross passages) at both the southern landfall and the northern landfall for construction of approach roads to the sub-sea TBM tunnels, of approximately 1.5 km in length;

íP          construction of northern landfall reclamation of approximately 16.5 hectares and about 2.0 km long seawalls;

íP          design and construction of ventilation buildings at the southern and northern landfalls;

íP          design and construction of at-grade roads at the southern and northern landfalls;

íP          construction of extension of the existing 4-cell box culvert adjacent to the River Trade Terminal (RTT);

íP          provision of a temporary pontoon for the affected existing Government berths;

íP          design and construction for modification of a section of vertical seawall of approximately 220m in length at the southern landfall to sloping seawall;

íP          design and construction of associated civil, structural, building, geotechnical, marine, environmental protection, drainage and sewerage, waterworks and utility works; and

íP          design and construction of advance SEM provision to facilitate installation of tunnel and route-wide E&M, TCSS and other utilities.

1.2                               Scope of the Enhanced TSP Monitoring Plan

This Enhanced TSP Monitoring Plan is prepared under Contract No HY/2012/08 which involves the construction of the Northern Connection in the Tuen Mun area.  While other construction works in the Tuen Mun area will be undertaken by Contracts III (ie construction of toll plaza), IV (construction of tunnel buildings) and V (installation of TCSS), respectively, and are thus outside the scope of the current Contract, this Enhanced TSP Monitoring Plan is applicable to the construction works of all contracts within the Tuen Mun area (ie Contracts II-V) under Condition 2.4 of EP-354/2009/A.          

1.3                               Works Programme

The construction works of the Northern Connection under Contract No. HY/2012/08 are anticipated to commence in November 2013.  The preliminary construction programme and the corresponding Contract components are provided in Figures 1.7 and 1.8, respectively. 

Given that other construction works within the Tuen Mun area (eg construction of the toll plaza, tunnel buildings and TCSS etc) will be undertaken under Contracts III, IV and V which have not been awarded yet (ie Contracts III, IV and V), the construction programmes are yet to be available.   

2                                   Enhanced TSP Monitoring

2.1                               Introduction

The following section provides the details of the Enhanced TSP Monitoring Plan to be undertaken by the Environmental Team (ET) under Condition 2.4 of EP-354/2009/A.  The objective of the enhanced monitoring of TSP is to provide an increased monitoring frequency of TSP to allow any deteriorating air quality to be readily detected and timely action taken to rectify the situation.  The enhanced monitoring also covers additional TSP monitoring station with a view to confirming that no unacceptable construction dust impact is detected at nearby sensitive receiver.  It should be noted that all relevant air quality mitigation measures recommended or specified in the EP, EIA, EM&A Manual, Environmental Management Plan, Method Statements, and General and Particular Specifications of this Project will be strictly followed to reduce potential construction dust impacts

Based on the findings presented in TM-CLKL EIA study, major construction dust nuisance is associated with exposed land-based site areas and the reclamation areas when the following construction activities are undertaken:

íP           Excavation;

íP           Road works;

íP           Slope works;

íP           Foundation works;

íP           Construction of road and superstructures;

íP           Wind erosion from reclaimed areas, open sites and stockpiling areas; and

íP           Demolition of existing structure.

Amongst the above construction activities, excavation, slope works, foundation works, construction of road and superstructures, wind erosion from reclaimed areas, open sites and stockpiling areas are the major sources of dust nuisance relevant to construction activities for the Northern Connection under Contract No. HY/2012/08 and other construction works within the Tuen Mun area under Contracts III, IV and V.  As such this Enhanced TSP Monitoring Plan is proposed to be implemented for these main types of construction activities.

2.2                               Monitoring Stations

The proposed monitoring stations for the enhanced TSP monitoring are shown in Figure 2.1 and detailed in Table 2.1. 

It is proposed that the monitoring locations will be designed to cover the dust-generating land-based construction works from the Northern Connection, toll plaza, tunnel buildings and TCSS to identify the direct impacts to air quality sensitive receivers (ASRs).   

As determined by the TM-CLKL EIA study, ASR1 and ASR5 are proposed in the approved EM&A Manual as the dust monitoring location for air quality monitoring during the construction phase.  Based on the requirements stated in the EM&A Manual, 1 set of 24-hour TSP and 3 sets of 1-hour TSP monitoring will be conducted at ASR1 and ASR5 at least once in every six days during the construction phase.  For the purpose of this Enhanced TSP Monitoring Plan, ASR1 and ASR5 will also be included as near-field monitoring stations for the construction activities of Northern Connection.    

Three additional monitoring stations, AQMS1, AQMS2 and ASR 10, are proposed in the Enhanced TSP Monitoring Plan.  AQMS1 is the abandoned Rive Trade Golf where the site office under Contract No. HY/2012/08 is located.  AQMS1 is at approximately 60 m to the west of the toll plaza works site and 270 m to the north of Northern Connection works boundary.  AQMS2 ([2]) is located at the bare ground in the proximity of the toll plaza works site and approximately 300 m to the northeast of Northern Connection works boundary.  These two stations are added to capture the dust impacts from the construction of the toll plaza.  They are also serving as mid-field monitoring stations for the construction of the Northern Connection.  The third additional station, ASR10, is located at the Butterfly Beach Park at 170 m to the east of the land-based works site boundary.  This is a far-field monitoring station which serves as a check-point to provide TSP measurements to indicate the background TSP levels of the Tuen Mun area. 

No far-field air quality monitoring station is proposed to the west of the works site boundary for the Enhanced TSP monitoring Plan since the area is industrial in nature and air quality is mainly affected by nearby activities such as operations of the Fill Bank at Tuen Mun Area 38 (TMFB).  It would thus be difficult to use data collected in this far field area to show any additional dust impacts from the TMCLKL works.  As such, additional TSP monitoring station is not considered necessary at this area.   

Given that no ASR is identified within the northern part of the works site boundary, and the construction works are marine-based in nature in the southern part of the works site boundary, no far-field air quality monitoring station is proposed for the Enhanced TSP Monitoring Plan in both the northern and southern parts of the works site. 

 

Table 2.1        Enhanced TSP Monitoring Plan íV Monitoring Stations

Air quality monitoring station

Location

Landuse

No. of Storey

Horizontal Distance to the Major Construction Area (m)

 

 

 

 

Northern Landfall

Toll Plaza

ASR1

Tuen Mun Fireboat Station

 

Office

1

 < 50

< 50

ASR5

Pillar Point Fire Station

 

Office

5

< 50

> 500

 

 

 

 

 

 

AQMS1

Previous River Trade Golf

 

Bare ground

 

0

270

60

AQMS2

Bare ground at Ho Suen Street

 

Bare ground

0

350

< 50

ASR10

Butterfly Beach Park

 

Recreational uses

0

> 1000

170

The status and locations of dust sensitive receivers may change after issue of this Enhanced TSP Monitoring Plan.  If this happens, the ET shall agree with the SOR, in consultation with the IEC, to propose the alternative/updated air quality monitoring station(s). 

2.3                               Monitoring Parameter

TSP levels have been proposed for measurement based on Supplementary Information that exceedances of the annual TSP criterion are predicted in the Pillar Point area during the construction phase of the Northern Connection and toll plaza.  1-hour and 24-hour TSP levels shall be measured to indicate the impacts of construction dust on air quality. 

In addition to the TSP measurements, all relevant data including weather conditions, elapsed-time meter reading for the start and stop of the sampler, identification and weight of the filter paper, any other special phenomena and work progress of the concerned site shall be recorded in detail by the ET.

2.4                               Monitoring Equipment & Methodology

The 1-hour and 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. 

The high volume samplers (HVS) 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.

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

íP           0.6-1.7 m3/min (20-60 SCFM) adjustable flow range;

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

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

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

íP           flow control accuracy: +/- 2.5% deviation over 24-hr sampling period;

íP           equipped with a shelter to protect the filter and sampler;

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

íP           equipped with a flow recorder for continuous monitoring;

íP           provided with a peaked roof inlet;

íP           equipped with a manometer;

íP           able to hold and seal the filter paper to the sampler housing in a horizontal position;

íP           easy to change the filter; and

íP           capable of operating continuously for 24-hr period.

The ET shall agree with the SOR, in consultation with the IEC, the position of the HVS.  When positioning the samplers, the following points shall be noted:

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

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

íP           a minimum of 2 m of separation from walls, parapets and penthouses is required for rooftop samplers;

íP           a minimum of 2 m of separation from any supporting structure, measured horizontally is required;

íP           no furnace or incinerator flue is nearby;

íP           airflow around the sampler is unrestricted;

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

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

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

íP           a secured supply of electricity is needed to operate the samplers; and

íP           no two samplers should be placed less than 2 m apart.

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 calibration data shall be properly documented for future reference by concerned parties, such as the IEC.  All the data shall be converted into standard temperature.  The flow-rate of the sampler before and after the sampling exercise with the filter in position shall be verified to be constant and recorded.

If direct reading dust meter is proposed to measure 1-hour TSP levels on an ad hoc basis, sufficient information shall be submitted to the IEC to prove that the instrument is capable of achieving a comparable result as that of the HVS and may be used for the 1-hour sampling.  The instrument should also be calibrated regularly and the 1-hour sampling shall be checked periodically by the HVS to check the validity and accuracy of the results measured by the direct reading method.

Wind data monitoring equipment will be set up at suitable location for logging the wind speed and wind direction at or near one of the air quality monitoring stations proposed in Table 2.1 which are located near the source of dust from the construction works area.  The wind data monitoring equipment should be installed and operated by considering the following conditions:

íP           the wind sensors should be installed on mast at an elevated level 10 m above ground so that they are clear of obstructions or turbulence caused by the buildings;

íP           the wind data should be captured by a data logger to be downloaded for processing at least once a month;

íP           the wind data equipment should be re-calibrated at least once every six months; and

íP           wind direction should be divided into 16 sectors of 22.5 degrees each.

In exceptional situations, the ET may propose alternative methods to obtain representative wind data upon approval from the SOR and agreement from the IEC.

2.5                               Laboratory Measurement and Analysis

A clean laboratory with constant temperature and humidity control and equipped with necessary measuring and conditioning instruments shall be used for sample analysis and equipment calibration and maintenance.  The laboratory shall be HOKLAS accredited.

Filter paper of size 8"x10" shall be labelled before sampling.  It shall be a clean filter paper with no pin holes and shall be conditioned in a humidity controlled chamber for over 24-hr and be pre-weighed before use for the sampling.

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 a readout down to 0.1 mg.  The balance shall be regularly calibrated against a traceable standard.  All the collected samples shall be kept in a good condition for 6 months before disposal.

2.6                               Monitoring Period and Frequency

2.6.1                           Enhanced TSP Monitoring Plan - Baseline

Baseline monitoring will be conducted to collect representative TSP data from the five monitoring stations.  This baseline monitoring will provide data for comparison with TSP data collected during the construction phase.

The baseline monitoring will be conducted at the air quality monitoring stations listed in Table 2.1 for 14 consecutive days prior to the start of the construction works to obtain daily 24-hour TSP samples.  1-hour sampling shall also be undertaken at least 3 times per day during the same period.  Monitoring shall take place prior to the commencement of any construction works of the Northern Connection, toll plaza, tunnel buildings and TCSS.  The proposed monitoring frequency is detailed in Table 2.2.

Table 2.2        Monitoring Frequency of Baseline Enhanced TSP Monitoring Plan

Monitoring Parameter

Monitoring Location

Frequency

Monitoring Condition

1-hour TSP

  ASR1, ASR5, ASR10, AQMS1, AQMS2

3 times per day for 14 consecutive days

Before commencement of any construction works of the Northern Connection, toll plaza, tunnel buildings and TCSS.

 

24-hour TSP

ASR1, ASR5, ASR10, AQMS1, AQMS2

Daily for 14 consecutive days

Before commencement of any construction works of the Northern Connection, toll plaza, tunnel buildings and TCSS

 

The monitoring schedule for baseline monitoring shall be developed by the ET and provided to the SOR and IEC for agreement prior to the monitoring works.

In the event that insufficient baseline monitoring data or questionable results are obtained, the ET shall liaise with the DEP to agree on an appropriate set of data to be used as a baseline reference and submit this data to the SOR and IEC for approval.

Ambient conditions may vary seasonally and shall be reviewed at three monthly intervals.  If the ET considers that the ambient conditions have changed and a repeat of the baseline monitoring is required to be carried out for obtaining 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 a change in ambient conditions be determined, the baseline levels and, in turn, the TSP Action and Limit Levels criteria, shall be revised.  The revised baseline levels and TSP Action and Limit Levels shall be agreed with the DEP and supplied to the IEC.

2.6.2                           Enhanced TSP Monitoring Plan - Construction Phase

The Enhanced TSP Monitoring Plan will be implemented simultaneously with the air quality impact monitoring in the EM&A programme.  In addition to the TSP monitoring at ASR1 and ASR5, monitoring will also be undertaken at the additional monitoring stations AQMS1, AQMS2 and ASR10 following the frequency of air quality impact monitoring stated in the EM&A Manual.  The data collected will be used to provide an indication of whether there is any significant increase in TSP levels upon commencement of construction activities of the Northern Connection, toll plaza and tunnel buildings.  TSP monitoring, including those required under the approved EM&A Manual (ie for ASR1 and ASR5 only) and this Enhanced TSP Monitoring Plan, will not be implemented during the TCSS installation works which will not involve any civil works.  

The major sources of dust nuisance arising from the Northern Connection, toll plaza and tunnel buildings are related to excavation, slope works, foundation works, construction of road and superstructures, wind erosion from reclaimed areas, open sites and stockpiling areas.  Therefore, during these construction activities, the TSP monitoring frequency will be increased at all air quality monitoring stations such that any deteriorating air quality can be readily detected and timely action taken to rectify the situation.  The Enhanced TSP Monitoring Plan during construction phase is summarized in Table 2.3. 

 

Table 2.3        Enhanced TSP Monitoring Plan íV Construction Phase

Monitoring Parameter

Monitoring Location

Frequency

Monitoring Condition (1)

1-hour TSP

ASR1, ASR5, ASR10, AQMS1, AQMS2

3 times per day every six days

Throughout the Northern Connection, toll plaza and tunnel buildings construction works

 

24-hour TSP

ASR1, ASR5, ASR10, AQMS1, AQMS2

Daily every six days

Throughout the Northern Connection, toll plaza and tunnel buildings construction works

 

1-hour TSP

ASR1, ASR5, ASR10, AQMS1, AQMS2

3 times per day every three days

Northern Connection

During excavation works for launching shaft, excavation work for Cut and Cover Tunnel and Cut and Cover Tunnel Construction

 

Toll Plaza

During excavation, slope works, construction of road and superstructures and wind erosion from open sites and stockpiling areas

 

Tunnel Buildings

During excavation, foundation works, construction of superstructures and wind erosion from open sites and stockpiling areas

 

24-hour TSP

ASR1, ASR5, ASR10, AQMS1, AQMS2

Daily every three days

Northern Connection

During excavation works for launching shaft, excavation work for Cut and Cover Tunnel and Cut and Cover Tunnel Construction

 

Toll Plaza

During excavation, slope works, construction of road and superstructures and wind erosion from open sites and stockpiling areas

 

Tunnel Buildings

During excavation, foundation works, construction of superstructures and wind erosion from open sites and stockpiling areas

Noted:

(1)   The Enhanced TSP Monitoring Plan will be undertaken when any of the monitoring condition(s) is triggered.  

A preliminary Enhanced TSP Monitoring Programme is provided in Figure 2.2.  The monitoring programme is developed based on the construction schedule supplied by the Contractor under the Contract No HY/2012/08, and will be agreed with EPD and supplied to the IEC.  The construction programmes of the toll plaza and tunnel buildings are not available during the preparation of this Plan since the construction contracts are not yet awarded.  The Enhanced TSP Monitoring Programme will be updated when the construction programmes of the toll plaza and tunnel buildings are available for consideration. 

The ET will notify the SOR and IEC at least one month before the monitoring frequency will be increased according to the Enhanced TSP Monitoring Plan (ie at least one month before commencement of relevant works for which increased monitoring frequency is required in accordance with Table 2.3).


Figure 2.2       Preliminary Monitoring Programme for Enhanced TSP Monitoring Plan (+)

Notes:
íž+íĘ: Enhanced TSP Monitoring will be undertaken during the entire construction period from November 2013 to July 2018 for the construction of the northern connection.

"#" : Baseline Monitoring

"@" : Increase TSP monitoring frequency (i.e. 1-hour TSP at ASR1, ASR5, ASR 10, AQMS 1 and AQMS 2 íV 3 times per day every three days; 24-hour TSP at ASR1, ASR5, ASR 10, AQMS 1 and AQMS 2 íV daily every three days) for the northern landfall construction.  TSP monitoring frequency will also be increased during construction of the toll plaza, tunnel buildings and TCSS when any of the monitoring conditions stated in Table 2.3 is triggered.

" * " : Construction works induce major dust nuisance

 


2.7                               Air Quality Compliance

The baseline monitoring results will form the basis for determining the Action and Limit Levels (A/L Levels) for the impact monitoring of the 24-hour TSP and 1-hour TSP levels.  According to the Supplementary Information on Construction Air Quality in Tuen Mun ([3]) (ížthe Supplementary InformationíĘ) submitted under Section 8.(1) of the EIAO for the Project, the annual average TSP results from EPD monitoring station in Yuen Long is ranged from 100 to 103 mg/m3 between 2003 to 2008 which exceeded the AQO criterion of annual TSP (80 mg/m3).  More recent information on annual average TSP levels, however, showed that exceedance of the AQO criterion was only recorded in 2011 during the period of 2009 to 2012 (2009: 77 mg/m3; 2010: 78 mg/m3; 2011: 86mg/m3; 2012: 68 mg/m3).  This annual AQO TSP criterion of 80 mg/m3 will also be adopted as the A/L Level of the Enhanced TSP Monitoring.  The proposed Action and Limit Levels are shown in Table 2.4. 

Table 2.4        Enhanced TSP Monitoring Plan íV TSP Action and Limit Level

Parameter

Action Level

Limit Level

24-hour TSP Level in mg/m3

For baseline level ≤ 200 mg/m³

Action level = (Baseline*1.3+ Limit level )/2

 

260

 

For baseline level >200 mg/m³

Action level = Limit level

 

1-hour TSP Level in mg/m3

For baseline level ≤ 384 mg/m³

Action level = (Baseline*1.3+ Limit level )/2

 

500

 

For baseline level > 384 mg/m³

Action level = Limit level

 

Annual Average 24-hour TSP Level in mg/m3

Action level = Limit level

80

 

The above A/L Levels are used to determine whether operational modifications are necessary to mitigate construction dust impacts, particularly in relation to reducing the TSP levels.  The impact monitoring results will be evaluated against the A/L Levels.  In the event that the A/L Levels are exceeded, appropriate actions in Event and Action plan (Table 2.5) should be undertaken and a review of works should be carried out by the Contractor(s). 

Any noticeable change to air quality will be recorded in the monitoring reports and will be investigated and remedial actions will be undertaken to reduce impacts.  Should exceedance be confirmed to be related to the works of the TM-CLKL Project, additional mitigation measures recommended in the Supplementary Information should be considered for implementation, including but not limited to the following:

íP         More frequent watering at the areas of exposed soil ([4]) ;

íP         Requiring that temporary hydroseeding of exposed surfaces which are not proposed to be touched for a period of time be undertaken;

íP         Implementing further dust suppression or screening measures at the concerned ASRs;

íP         Scheduling the works to avoid key dusty construction activities of concurrent contracts where possible; and

íP         Stoppage of construction works would be taken if deemed necessary to mitigate any project-related upsurge of TSP level.

Particular attention will be paid to the Contractor(s)íŽs implementation of the recommended dust-reducing mitigation measures.

 


Table 2.5        Enhanced TSP Monitoring Plan íV Event and Action Plan

Event

Action

 

ET (a)

IEC (a)

SOR (a)

Contractor(s)

Action Level

 

 

 

 

Exceedance recorded

1.        Identify the source.

2.                 Repeat measurement to confirm finding.  If two consecutive measurements exceed Action Level, the exceedance is then confirmed.

3.                 Inform the IEC and the SOR. 

4.                 Investigate the cause of exceedance and check ContractoríŽs working procedures to determine possible mitigation to be implemented.

5.                 If the exceedance is confirmed to be Project related after investigation, increase monitoring frequency to daily.

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

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

8.                 If exceedance stops, cease additional monitoring.

 

1.     Check monitoring data submitted by the ET.

2.     Check the ContractoríŽs working method.

3.     If the exceedance is confirmed to be Project related after investigation, discuss with the ET and the Contractor on possible remedial measures.

4.     Advise the SOR on the effectiveness of the proposed remedial measures.

5.     Supervisor implementation of remedial measures.

1.     Confirm receipt of notification of failure in writing.

2.     Notify the Contractor.

3.     Ensure remedial measures properly implemented.

1.     Rectify any unacceptable practice

2.     Amend working methods if appropriate

3.     If the exceedance is confirmed to be Project related, submit proposals for remedial actions to IEC within 3 working days of notification

4.     Implement the agreed proposals

5.     Amend proposal if appropriate

Limit Level

 

 

 

 

Exceedance

recorded

1.     Identify the source.

2.     Repeat measurement to confirm finding. If two consecutive measurements exceed Limit Level, the exceedance is then confirmed.

3.     Inform the IEC, the SOR, the DEP and the Contractor.

4.     Investigate the cause of exceedance and check ContractoríŽs working procedures to determine possible mitigation to be implemented.

5.     If the exceedance is confirmed to be Project related after investigation, increase monitoring frequency to daily.

6.     Carry out analysis of the ContractoríŽs working procedures to determine possible mitigation to be implemented.

7.     Arrange meeting with the IEC and the SOR to discuss the remedial actions to be taken.

8.     Assess effectiveness of the ContractoríŽs remedial actions and keep the IEC, the DEP and the SOR informed of the results.

9.     If exceedance stops, cease additional monitoring.

1.     Check monitoring data submitted by the ET.

2.     Check ContractoríŽs working method.

3.     If the exceedance is confirmed to be Project related after investigation, discuss with the ET and the Contractor on possible remedial measures.

4.     Advise the SOR on the effectiveness of the proposed remedial measures.

5.     Supervisor implementation of remedial measures.

 

1.     Confirm receipt of notification of failure in writing.

2.     Notify the Contractor.

3.     If the exceedance is confirmed to be Project related after investigation, in consultation with the IEC, agree with the Contractor on the remedial measures to be implemented.

4.     Ensure remedial measures are properly implemented.

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

1.     Take immediate action to avoid further exceedance.

2.     If the exceedance is confirmed to be Project related after investigation, submit proposals for remedial actions to IEC within 3 working days of notification.

3.     Implement the agreed proposals.

4.     Amend proposal if appropriate.

5.     Stop the relevant activity of works as determined by the SOR until the exceedance is abated.

Note: (a)  ET íV Environmental Team; IEC íV Independent Environmental Checker; SOR íV Supervising OfficeríŽs Representative

 

3                                   Results and Reporting

3.1                               Baseline Monitoring

The Baseline Monitoring Report will describe the baseline monitoring requirements presented in Section 2 and weather data, and present the baseline monitoring results.  The laboratory analysis reports will be appended in the report.  The requirements of Baseline Monitoring Report stipulated in Section 12.4 of the ProjectíŽs EM&A Manual will be followed.

3.2                               Impact Monitoring

The monitoring results during impact monitoring will be compared with the baseline monitoring results and evaluate against the proposed Action/Limit levels in this Enhanced TSP Monitoring Plan.  Monitoring results during the construction phase together with the findings will be presented in the Monthly EM&A Reports.  Annual average TSP level during the construction phase with the findings will be presented in the Annual EM&A Reports.

 


 



([1])       EIA reports related to HZMB.  Supplementary Information on Construction Air Quality in Tuen Mun.  Further information submitted under Section 8.(1) of the Ordinance.  Available from http://www.epd.gov.hk/eia/register/report/eiareport/eia_1742009/further_info/pdf/Supplementary%20Details%20for%20ACE%20R6%20-%20marked%20up%20EPD%202509.htm

([2])        AQMS2 is an alternative monitoring station for Butterfly Laundry which is an ASR (ie ASR6) identified in the approved EIA Report.  AQMS2 is being proposed for monitoring since access to Butterfly Laundry is not granted to the ET at the moment to undertake the air quality monitoring.  Should access be granted to the ET, air quality monitoring will be undertaken at Butterfly Laundry instead of AQMS2 in the impact monitoring phase.

([3])       EIA reports related to HZMB.  Supplementary Information on Construction Air Quality in Tuen Mun.  Further information submitted under Section 8.(1) of the Ordinance.  Available from http://www.epd.gov.hk/eia/register/report/eiareport/eia_1742009/further_info/pdf/Supplementary%20Details%20for%20ACE%20R6%20-%20marked%20up%20EPD%202509.htm

([4])        Currently, the Contractor is required to undertake watering at least 12 times per day for the Tuen Mun area.  The time intervals between each watering should not exceed 1.5 hours.