Job No.: TCS00874/16

 

 

 

 

 

 

 

 

 

CEDD Contract No. CV/2012/05

Development of a Bathing Beach at Lung Mei, Tai Po

 

 

 

 

 

 

 

 

 

Baseline Monitoring Report
(Air Quality & Noise)

 

 

 

 

 

 

 

 

 

 

Prepared For

 

 

 

 

Welcome Construction CO., Ltd

 

 

 

 

 

 

 

 

 

 

Date

Reference No.

Prepared By

Certified By

7 August 2017

TCS00874/16/600/R0022v3

Donald Kwok

Assistant Environmental Consultant

T.W. Tam

Environmental Team Leader

 

Version

Date

Remarks

1

29 June 2017

First Submission

2

20 July 2017

Amended according to the IEC’s comment on 18 July 2017

3

7 August 2017

Amended according to the IEC’s comment on 31 July 2017

 

 

 

 

 

 


 

 

 

 

 

 

 

executive summary

ES.01     Civil Engineering and Development Department (hereafter referred as “CEDD”) is the Project Proponent and the Permit Holder of Agreement No. CE 59/2005 (EP) Development of a Bathing Beach at Lung Mei, Tai Po (hereinafter referred as “the Project”), which is a Designated Project to be implemented under Environmental Permit number EP-388/2010 (hereinafter referred as “the EP-388/2010” or “the EP”).

ES.02     Action-United Environmental Services & Consulting (hereinafter referred as “AUES”) has been commissioned as the Environmental Team for the Project (hereinafter referred as “the ET”) to perform relevant Environmental Monitoring and Audit (EM&A) programme, including baseline and impact environmental monitoring in accordance with the EM&A Manual approved under the Environmental Impact Assessment Ordinance (EIAO).

ES.03     According to the Approved Environmental Monitoring and Audit (EM&A) Manual [November 2007] (hereinafter referred as ‘the EM&A Manual’), air quality, construction noise and water quality monitoring should be required to be monitored during the construction phase of the Project.  Moreover, baseline environmental monitoring for air quality and water quality is required to be conducted prior to commencement of the construction works/activities under the Project. 

ES.04     A total of 14 consecutive day baseline monitoring of air quality have been undertaken at the proposed monitoring locations from 7 June 2017 to 20 June 2017.  For baseline monitoring of noise, it has been undertaken from 7 June 2017 to 23 June 2017.  During the baseline monitoring period, no construction activities under the Project or other external influencing factors of significant concern were observed by ET.

ES.05     This report summarizes the key findings and presents the process and rationale behind determining a set of Action and Limit Levels (A/L Levels) of air quality based on the baseline data.  These A/L Levels will serve as the yardsticks for assessing the acceptability of the environmental impact during construction phase of the Project Works impact monitoring.  They are statistical in nature and derived according to the criteria set out in the EM&A Manual.

ES.06     Results of the derived Action and Limit Levels for the air quality and noise are given in Tables ES-1, ES-2 and ES-2 as follows.

Table ES-1        Action and Limit Levels of Air Quality Monitoring

Monitoring Station

Action Level (mg /m3)

Limit Level (mg/m3)

1-hour TSP

24-hour TSP

1-hour TSP

24-hour TSP

A4

275

142

500

260

A7

274

141

500

260

Remark:    Upon received IEC verify and EPD endorse, alternative locations A7 will replace A6 respectively and to performed the baseline and impact monitoring of EM&A program.

Table ES-2        Action and Limit Levels of Construction Noise Monitoring

Monitoring Location

Action Level

Limit Level in dB(A)

Time Period: 0700-1900 hours on normal weekdays

N1

When one or more documented complaints are received

75 dB(A)

N2a

N3a

N4

 

ES.07     In cases where exceedance of these criteria occurs, actions should be carried out in accordance with the Event Action Plan as shown the EM&A Manual.


Table of Contents

1     Introduction   1

1.1            Project Background   1

1.2            Report Structure  1

2     Summary of Baseline Monitoring Requirement   2

2.1            General  2

2.2            Monitoring Parameters  2

2.3            Monitoring Locations  2

2.4            Monitoring Frequency and Period   3

2.5            Monitoring Equipment  4

2.6            Derivation of Action/Limit (A/L) Levels  4

3     Baseline monitoring methdology   6

3.1            General  6

3.2            Location of Baseline Monitoring   6

3.3            Monitoring Equipment at Baseline Monitoring   6

3.4            Monitoring Procedures  6

3.5            Data Management and Data QA/QC Control  8

4     Baseline Monitoring Results  9

4.1            General  9

4.2            Results of Air Quality Monitoring   9

4.3            Results of Noise Monitoring   10

4.4            Discussion and Recommendations  11

5     Conclusions and Recommentations  12

5.1            Conclusions  12

5.2            Recommendations  12

 


List of TABLES

Table 2-1        Summary of EM&A Requirements

Table 2-2        Designated Air Quality Monitoring Station according to the EM&A Manual

Table 2-3        Summary of Baseline Air Quality Monitoring Stations

Table 2-4        Designated Noise Monitoring Station according to the EM&A Manual

Table 2-5        Summary of Baseline Noise Monitoring Stations

Table 2-6        Derivation of Action and Limit Levels for Air Quality

Table 2-7        Derivation of Action and Limit Levels for Construction Noise

Table 3-1        Air Quality Monitoring Equipment

Table 3-2        Construction Noise Monitoring Equipment

Table 4-1        Summary of 24-hour and 1-hour TSP Monitoring Results – A4

Table 4-2        Summary of 24-hour and 1-hour TSP Monitoring Results – A7

Table 4-3        Action and Limit Levels for Air Quality Monitoring for all Stations

Table 4-4        Summaries of Noise Monitoring Results

Table 4-5        Action and Limit Levels of Construction Noise Monitoring

 

 

List of Appendices

Appendix A    Layout Plan of the Project

Appendix B    Designated Monitoring Locations – Air Monitoring & Noise Monitoring

Appendix C    Monitoring Location Photographic Record

Appendix D    Event and Action Plan

Appendix E    Valid Calibration Certificate of Monitoring Equipment

Appendix F     HOKLAS-accreditation Certificate of the Testing Laboratory.

Appendix G   Baseline Monitoring Schedules

Appendix H    Meteorological Data during Baseline Monitoring (Tai Po Station/ Tai Mei Tuk Station)

Appendix I     Monitoring Results Data of the air quality (24-hour TSP & 1-hour TSP) and Noise and

Appendix J     Laboratory Data Report (Air Quality - 24-hour TSP)

 

 

 

 


1                             Introduction

1.1              Project Background

1.1.1                 Civil Engineering and Development Department (hereafter referred as “CEDD”) is the Project Proponent and the Permit Holder of Agreement No. CE 59/2005 (EP) Development of a Bathing Beach at Lung Mei, Tai Po (hereinafter referred as “the Project”), which is a Designated Project to be implemented under Environmental Permit number EP-388/2010 (hereinafter referred as “the EP-388/2010” or “the EP”). 

 

1.1.2                 The major construction activities of the Project comprise construction 200-metre long bathing beach with a groyne at each end, a shark prevention net; a public car park; retaining walls; and the associated roadworks, drainage and sewerage works.  Layout plan of the Project is shown in Appendix A.

 

1.1.3                 Furthermore, the project works is under Environmental Permit (EP) No. EP-388/2010 as a Designated Project and the designated works include:

(i)            Construction of a 200m long beach with a groyne at each end of the beach which includes dredging and sandfilling works;

(ii)          Construction of one culvert at the eastern side of the beach and another small section of culvert and open drainage channel with gabion embankments at the western end, both to collect and divert surface runoff from upstream locations; and

(iii)        Construction of a beach building with associated beach building facilities, kiosk and a carpark and associated road improvement works adjoining the facility.

 

1.1.4                 Action-United Environmental Services & Consulting (hereinafter referred as “AUES”) has been commissioned as an Independent Environmental Team (hereinafter referred as “the ET”) to implement the relevant EM&A program in accordance with the approved EM&A Manual, as well as the associated duties.  As part of the EM&A program, baseline monitoring is required to determine the ambient environmental conditions.  Therefore, baseline monitoring of air quality was undertaken on 7 June 2017 to 20 June 2017 and for noise was carried out on 7 June 2017 to 23 June 2017 before construction work commencement.  With regard to the baseline water quality monitoring, it will be carried out prior to the commencement of dredging and sandfilling activities and the relevant baseline monitoring report will be provided stand-alone.

 

1.1.5                 During the baseline monitoring period for air quality and noise, there were no construction activities of this project or other external influencing factors of significant concern observed by the ET.

 

1.1.6                 This Baseline Monitoring Report presents the details of the baseline study including project background, monitoring methodology, monitoring results, summary of findings, and Action/Limit (A/L) Levels established for subsequent use in the Project construction phase EM&A program.

 

1.2              Report Structure

1.2.1                 The Baseline Monitoring Report is structured into the following sections:-

Section 1    Introduction

Section 2    Summaries of Baseline Monitoring Requirement.

Section 3    Baseline Monitoring Methodology

Section 4    Baseline Monitoring Results

Section 5    Conclusion and Recommendation

 


2                             Summary of Baseline Monitoring Requirement

2.1              General

2.1.1                 The Environmental Monitoring and Audit requirements are set out in the EM&A manual. Environmental issues such as air quality and construction noise were identified as the key issues during the construction phase of the Project.  A summary of the baseline EM&A requirements for air and noise monitoring are presented in the sub-sections below.

 

2.2              Monitoring Parameters

2.1.2                 According to the EM&A Manual, baseline monitoring shall only cover air quality.  However, in order to obtain the baseline noise condition before commencement of the Project, as agreed by the Contractor, baseline noise monitoring shall be included in baseline monitoring programme.

 

2.2.1                 A summary of the monitoring parameters is presented in Table 2-1 below.

Table 2-1         Summary of EM&A Requirements

Environmental Issue

Parameters

Air Quality

Ÿ  1-hour TSP

Ÿ  24-hour TSP

Noise (#)

Ÿ   Leq (30min) in six consecutive Leq(5 min) between 07:00-19:00 on normal weekdays

Ÿ   3 sets of consecutive Leq (5min) on restricted hours i.e. public holiday or Sunday

Ÿ   Statistical result such as L10 and L90 for supplementary information

Remark (#)  Since there are no requirements for baseline noise monitoring in the EM&A Manual, the monitoring parameters are based on the general practice of the EM&A programme.

 

2.3              Monitoring Locations

Air Quality

2.3.1                 Two designated air quality monitoring locations are recommended in Section 3.1 of the EM&A Manual and they are listed in Table 2-2 below and illustrated in Appendix B. 

Table 2-2        Designated Air Quality Monitoring Station according to the EM&A Manual

ASR

Location

A4

No. 101 Lung Mei Tsuen

A6

No. 79 Lo Tsz Tin Tsuen

 

2.3.2                 During liaison with the landlord of A6, he refused to provide access and location for installation of HVAS.  Therefore, alternative location (A7) was proposed by ET in accordance with Section 3.4 of the EM&A Manual.  The proposed alternative locations are considered capable of effectively representing the baseline conditions at the impact monitoring locations.  The proposal (ref no.: TCS00874/16/300/L0016b) for alternative monitoring locations was verified IEC and it has been submitted to EPD for approval on 2 May 2017.

 

2.3.3                 The baseline air quality monitoring locations are in Table 2-3 and illustrated in Appendix B.

Table 2-3        Summary of Baseline Air Quality Monitoring Stations

Station ID

Location

Justification

A4

No. 101 Lung Mei Tsuen

No changes.

A7

Hong Kong Eco-Farm

It is one of the representative ASR identified in the EIA which located at north-east of the site. Granted with the area and power provision for HVS.

 

 

Construction Noise

2.3.4                 According to Section 4.1 of the EM&A Manual, four designated noise sensitive receivers (NSR) were recommended and they are listed in Table 2-4 and illustrated in Appendix B.

Table 2-4        Designated Noise Monitoring Station according to the EM&A Manual

NSR

Location

N1

Village house - No. 165A Lung Mei

N2*

Village house - No. 103 Lung Mei

N3

Village house - No. 70 Lo Tsz Tin

N4

Village house - No. 79 Lo Tsz Tin

Remarks: (*)           Noise monitoring should be conducted at N2a (i.e House No. 101 Lung Mei) if it is changed to residential use during construction phase.

 

2.3.5                 As confirmed on the first day of baseline monitoring, N2a (House no. 101 Lung Mei) has been changed to residential use.  Therefore, the baseline noise monitoring is conducted at N2a and to replace N2.  Moreover, due to the lack of accessibility of noise monitoring at NSR N3 (Village house – No. 70 Lo Tsz Tin), alternative location was proposed to replace N3 to carry out the baseline noise monitoring.  Having reviewed the surrounding condition, NSR N3a (Village house – No. 66C Lo Tsz Tin) was proposed with the rationales summarized in below.

 

1)         The distance between N3 and N3a is about 18 meter apart and N3a locates at close proximity of the project site and major site activities which are likely to have noise impacts;

2)         N3a is a village type residential house and it is a noise sensitive receiver (NSR);

3)         Accessibility for noise monitoring work at N3a is available; and

4)         Minimal disturbance would be only caused to the proposed monitoring location N3a.

 

2.3.6                 The proposed location N3a was accepted by IEC and the NSRs for the baseline noise monitoring are listed in Table 2-5 and illustrated in Appendix B.

Table 2-5        Summary of Baseline Noise Monitoring Stations

Station ID

Description

N1

Village house - No. 165A Lung Mei

N2a

Village house - No. 101 Lung Mei

N3a

Village house - No. 66C Lo Tsz Tin

N4

Village house - No. 79 Lo Tsz Tin

 

2.4              Monitoring Frequency and Period

2.4.1                 The baseline monitoring will be conducted immediately prior to commencement of the construction work under the Project.  No construction activities are allowed to be undertaken during the baseline monitoring period.

 

Air Quality Monitoring

2.4.2                 Monitoring frequency for air quality baseline monitoring is as follows:

Frequency:

        Daily for 24-hour TSP

        Three times a day for 1-hour TSP while the highest dust impact is    expected.

Duration:

14 consecutive days

 

Noise Monitoring

Frequency:

        Leq (30min) in 6 consecutive Leq(5min) between 07:00-19:00 on normal weekdays

        3 sets of consecutive Leq(5min) on restricted hours i.e. public holiday or Sunday

         L10 and L90 for reference

Duration:

Two weeks

2.5              Monitoring Equipment

Air Quality Monitoring

2.5.1                 The 24-hour and 1-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.  If the ET proposes to use a direct reading dust meter to measure 1-hour TSP levels, it shall submit sufficient information to the IEC to prove that the instrument is capable of achieving a comparable results to the HVS.  The instrument should be calibrated regularly, and the 1-hour sampling shall be determined on yearly basis by the HVS to check the validity and accuracy of the results measured by direct reading method. The filter paper of 24-hour TSP measurement shall be determined by HOKLAS accredited laboratory.

 

Noise Monitoring

2.5.2                 Sound level meter in compliance with the International Electrotechnical Commission Publications 651: 1979 (Type 1) and 804: 1985 (Type 1) specifications shall be used for carrying out the noise monitoring.  The sound level meter shall be checked using an acoustic calibrator.  The wind speed shall be checked with a portable wind speed meter capable of measuring the wind speed in ms-1.

 

Wind Data Monitoring Equipment

2.5.3                 Meteorological information, including wind direction, wind speed, humidity, rainfall, air pressure and temperature etc., which in general is required for evaluating the air quality impact will be extracted from the Hong Kong Observatory including Tai Po Station (Air Temperature/Pressure and Relative Humidity) and Tai Mei Tuk Station (wind speed and direction).

 

2.5.4                 Two obvious advantages of using the HKO meteorological information are:

(i)        Installation of a wind sensor of 10 metres aboveground, according to the EM&A Manual, involves construction of the foundation for the reasonably strong 10 meter metal pole, which, according to the ET’s past experience, may provoke fierce opposition of the ASR owners, and is therefore hardly to be practicable under limited time and resources; and

(ii)      HKO meteorological information is widely accepted to be used in many environmental reports within HKSAR due to its professional quality and precision, in addition to its readily availability and accessibility via the HKO website.

 

2.6              Derivation of Action/Limit (A/L) Levels

2.6.1                 The baseline results form the basis for determining the environmental acceptance criteria for the impact monitoring.  A summary of derivation of Action/Limit (A/L) Levels for air quality and construction noise are shown in Table 2-6 and 2-7 respectively.

Table 2-6        Derivation of Action and Limit Levels for Air Quality

Parameter

Action Level

Limit Level

24-hour TSP

For baseline level £ 200 mg/m3:

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

260 mg/m3

For baseline level > 200 mg/m3:

Action level = Limit level

1-hour TSP

For baseline level £ 384 mg/m3:

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

500 mg/m3

For baseline level > 384 mg/m3:

Action level = Limit level

 

Table 2-7         Derivation of Action and Limit Levels for Construction Noise

Time Period

Action Level in dB(A)

Limit Level in dB(A)

0700-1900 hours on normal weekdays

When one documented complaint is received

75* dB(A)

Note:     (*)      Reduces to 70 dB(A) for schools and 65 dB(A) during the school examination periods.

2.6.2                 Should non-compliance of the environmental quality criteria occurs, remedial actions will be triggered according to the Event and Action Plan which presented in Appendix D.

 


3                             Baseline monitoring methdology

3.1              General

3.1.1                 The baseline monitoring program of air quality was conducted on 7 June 2017 to 20 June 2017; and noise was conducted from 7 June 2017 to 23 June 2017.  During the baseline monitoring period, there were no construction activities of this project or other external influencing factors of significant concern observed by the ET.

 

3.2              Location of Baseline Monitoring

3.2.1                 Baseline air quality and noise monitoring have been undertaken at the all monitoring stations from 7 June 2017 to 20 June 2017 and 7 June 2017 to 23 June 2017 respectively.  The detailed information of monitoring stations to be referred to Tables 2-4 and 2-5, and the photographic record of the monitoring locations are shown in Appendix C.

 

3.3              Monitoring Equipment at Baseline Monitoring

3.3.1                 All equipment to be used for baseline air quality monitoring is listed in Table 3-1.

Table 3-1         Air Quality Monitoring Equipment

Equipment

Model

24-Hour TSP

High Volume Air Sampler

TISCH High Volume Air Sampler, HVS Model TE-5170

Calibration Kit

TISCH Calibration Kit Mode TE-5025A

1-Hour TSP

Portable Dust Meter

Sibata LD-3B Laser Dust Meter

 

3.3.2                 Noise monitoring equipment to be used for baseline monitoring is listed in Table 3-2.

Table 3-2         Construction Noise Monitoring Equipment

Equipment

Model

Integrating Sound Level Meter

B&K Type 2238 or Rion NL-31 or Rion NL-52

Calibrator

B&K Type 4231 or Rion NC-74

Portable Wind Speed Indicator

Anemometer AZ Instrument 8908

 

3.4              Monitoring Procedures

3.4.1                 The procedures to conduct air quality and noise monitoring are summarized in following sub-sections.

 

Air Quality

1-hour TSP

3.4.2                 Operation of the 1-hour TSP meter will follow manufacturer’s Operation and Service Manual.

 

3.4.3                 The 1-hour TSP monitor, brand named Sibata LD-3B Laser Dust Meter” is a portable, battery-operated laser photometer. The 1-hour TSP meter provides a real time 1-hour TSP measurement based on 900 light scattering. The 1-hour TSP monitor consists of the following:

a.         A pump to draw sample aerosol through the optic chamber where TSP is measured;

b.         A sheath air system to isolate the aerosol in the chamber to keep the optics clean for maximum reliability; and

c.          A built-in data logger compatible with Windows based program to facilitate data collection, analysis and reporting.

 

3.4.4                 The 1-hour TSP meter to be used will be within the valid period, calibrated by the manufacturer prior to purchasing. Zero response of the instrument will be checked before and after each monitoring event.  Annually calibration with the High Volume Sampler (HVS) in same condition would be undertaken by the Laboratory.

 

24-hour TSP

3.4.5                 The equipment used for 24-hour TSP measurement is the High Volume Sampler (hereinafter the “HVS”) brand named TISCH, Model TE-5170 TSP High Volume Air Sampler, which complied with EPA Code of Federal Regulation, Appendix B to Part 50. The HVS consists of the following:

 

a.              An anodized aluminum shelter;

b.             A 8”x10” stainless steel filter holder;

c.              A blower motor assembly;

d.             A continuous flow/pressure recorder;

e.              A motor speed-voltage control/elapsed time indicator;

f.              A 7-day mechanical timer, and

g.              A power supply of 220v/50 hz

 

3.4.6                 For HVS for 24-hour TSP monitoring, the HVS is mounted in a metallic cage with a top for protection and also it is sat on the existing ground or the roof of building.  The flow rate of the HVS between 0.6m3/min and 1.7m3/min will be properly set in accordance with the manufacturer’s instruction to within the range recommended in EPA Code of Federal Regulation, Appendix B to Part 50.  Glass Fiber Filter 8" x 10" of TE-653 will be used for 24-Hour TSP monitoring and would be supplied by laboratory.  The general procedures of sampling are described as below:-

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

Ÿ   No two samplers should be placed less than 2 meters apart;

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

Ÿ   A minimum of 2 meters of separation from any supporting structure, measured horizontally is required;

Ÿ   Before placing any filter media at the HVS, the power supply will be checked to ensure the sampler work properly;

Ÿ   The filter paper will be set to align on the screen of HVS to ensure that the gasket formed an air tight seal on the outer edges of the filter.  Then filter holder frame will be tightened to the filter hold with swing bolts.  The holding pressure should be sufficient to avoid air leakage at the edge.

Ÿ   The mechanical timer will be set for a sampling period of 24 hours (00:00 mid-night to 00:00 mid-night next day).  Information will be recorded on the field data sheet, which would be included the sampling data, starting time, the weather condition at current and the filter paper ID with the initial weight;

Ÿ   After sampling, the filter paper will be collected and transfer from the filter holder of the HVS to a sealed envelope and sent to a local HOKLAS accredited laboratory for quantifying.

 

3.4.7                 All the sampled 24-hour TSP filters will be collected and put into the filter envelope provided by the laboratory.  The sample will be kept in normal air conditioned room conditions, i.e. 70% HR (Relative Humidity) and 25oC and delivery to the office within 48 hours and sent to laboratory for analysis.  The sampled filter will be kept in the laboratory for six months prior to disposal.

 

3.4.8                 The HVS used for 24-hour TSP monitoring will be calibrated before the commencement for sampling, and after in two months interval for 1 point checking of maintenance and six months interval for five points calibrate in accordance with the manufacturer’s instruction using the NIST-certified standard calibrator (Tisch Calibration Kit Model TE-5025A) to establish a relationship between the follow recorder meter reading in cfm (cubic feet per minute) and the standard flow rate, Qstd, in m3/min.  Motor brushes of HVS will be regularly replaced of about five hundred hours per time.

Construction Noise

3.4.9                 As referred to in the Technical Memorandum (TM) issued under the NCO, sound level meters in compliance with the International Electrotechnical Commission Publications 651: 1979 (Type 1) and 804:1985 (Type 1) specifications shall be used for carrying out the noise monitoring. Immediately prior to and following each noise measurement the accuracy of the sound level meter shall be checked using an acoustic calibrator generating a known sound pressure level at a known frequency. Measurements may be accepted as valid only if the calibration levels from before and after the noise measurement agree to within 1.0 dB.

 

3.4.10             All noise measurements will be performed with the meter set to FAST response and on the A-weighted equivalent continuous sound pressure level (Leq).  Leq(30 min) in six consecutive Leq(5 min) measurements will be used as the monitoring parameter for the time period between 07:00-19:00 hours on weekdays and 3 sets of consecutive Leq(5min) on restricted hours i.e. public holiday or Sunday throughout the baseline period.

 

3.4.11             The sound level meter will be mounted on a tripod at a height of 1.2 m and placed at the assessment point and oriented such that the microphone is pointed to the site with the microphone facing perpendicular to the line of sight. The windshield will be fitted for all measurements. Where a measurement is to be carried out at a building, the assessment point would normally be at a position 1 m from the exterior of the building façade. Where a measurement is to be made for noise being received at a place other than a building, the assessment point would be at a position 1.2 m above the ground in a free-field situation, i.e. at least 3.5 m away from reflective surfaces such as adjacent buildings or walls.

 

3.4.12             Immediately prior to and following each noise measurement the accuracy of the sound level meter will be checked using an acoustic calibrator generating a known sound pressure level at a known frequency.  Measurements will be accepted as valid only if the calibration level from before and after the noise measurement agrees to within 1.0 dB.

 

3.4.13             Noise measurements will not be made in fog, rain, wind with a steady speed exceeding 5m/s or wind with gusts exceeding 10m/s. The wind speed will be checked with a portable wind speed meter capable of measuring the wind speed in m/s.

 

3.4.14             The calibration certificates of monitoring equipment of air quality and noise and the HOKLAS-Accreditation certificate of the testing laboratory is shown in Appendices E and F.

 

Meteorological Information

3.4.15             The meteorological information including wind direction, wind speed, humidity, rainfall, air pressure and temperature etc. during baseline monitoring is extracted from the closest Hong Kong Observatory Station.  To obtain the most appropriate meteorological information where available, Air Temperature/Pressure and Relative Humidity will be extracted from Tai Po Station and wind speed and direction will be extracted from Tai Mei Tuk Station.

 

3.5              Data Management and Data QA/QC Control

3.5.1                 The baseline monitoring data were handled by the ET’s in-house data recording and management system.

 

3.5.2                 The monitoring data recorded in the equipment were downloaded directly from the equipment at the end of each monitoring day.  The downloaded monitoring data were input into a computerized database properly maintained by the ET.  The laboratory results were input directly into the computerized database and checked by personnel other than those who input the data.

 

3.5.3                 For monitoring parameters that require laboratory analysis, the local laboratory shall follow the QA/QC requirements as set out under the HOKLAS scheme for the relevant laboratory tests.


4                             Baseline Monitoring Results

4.1              General

4.1.1                 The baseline monitoring schedules are presented in Appendix G and the monitoring results are detailed in the following sub-sections.

 

4.2              Results of Air Quality Monitoring

4.2.1                 Baseline air quality monitoring was carried out form 7 June 2017 to 20 June 2017.  The results for 24-hour and 1-hour TSP are summarized in Tables 4-1 to 4-2.  The 24-hour TSP data are shown in Appendix I and the laboratory report record are shown in Appendix J.

Table 4-1         Summary of 24-hour and 1-hour TSP Monitoring Results – A4

Date

24-hour TSP (mg/m3)

1-hour TSP (mg/m3)

Date

Start Time

1st Measurement

2nd Measurement

3rd Measurement

7-Jun-17

17

7-Jun-17

9:40

26

21

18

8-Jun-17

14

8-Jun-17

13:11

34

36

34

9-Jun-17

14

9-Jun-17

13:16

33

32

32

10-Jun-17

13

10-Jun-17

13:15

40

40

36

11-Jun-17

16

11-Jun-17

13:18

34

40

37

12-Jun-17

15

12-Jun-17

10:37

33

39

38

13-Jun-17

22

13-Jun-17

14:32

30

31

29

14-Jun-17

29

14-Jun-17

13:21

28

27

29

15-Jun-17

22

15-Jun-17

13:31

35

31

37

16-Jun-17

22

16-Jun-17

13:02

69

57

63

17-Jun-17

17

17-Jun-17

14:16

40

40

41

18-Jun-17

22

18-Jun-17

9:14

49

48

41

19-Jun-17

11

19-Jun-17

13:39

42

46

38

20-Jun-17

22

20-Jun-17

13:37

37

41

47

Average

(Range)

18

(11-29)

Average

(Range)

38

(18-69)

 

Table 4-2         Summary of 24-hour and 1-hour TSP Monitoring Results – A7

Date

24-hour TSP (mg/m3)

1-hour TSP (mg/m3)

Date

Start Time

1st Measurement

2nd Measurement

3rd Measurement

7-Jun-17

7

7-Jun-17

9:55

25

29

22

8-Jun-17

11

8-Jun-17

13:07

33

26

27

9-Jun-17

15

9-Jun-17

13:12

29

45

31

10-Jun-17

12

10-Jun-17

13:11

36

37

38

11-Jun-17

16

11-Jun-17

13:21

36

35

36

12-Jun-17

18

12-Jun-17

10:33

29

33

31

13-Jun-17

21

13-Jun-17

14:29

32

36

32

14-Jun-17

28

14-Jun-17

13:17

30

30

40

15-Jun-17

24

15-Jun-17

13:18

34

40

42

16-Jun-17

21

16-Jun-17

13:17

53

63

52

17-Jun-17

19

17-Jun-17

14:10

40

39

40

18-Jun-17

24

18-Jun-17

9:03

50

48

42

19-Jun-17

16

19-Jun-17

13:28

46

41

43

20-Jun-17

15

20-Jun-17

13:20

32

28

38

Average

(Range)

17

(7-28)

Average

(Range)

37

(22-63)

 

4.2.2                 The meteorological data during the baseline monitoring period are summarized in Appendix H.

 

Action/Limit Levels for Air Quality

4.2.3                 Following the criteria shown in Table 2-6 of this report, the proposed Action and Limit Levels for 24-hour and 1-hour TSP are listed in Table 4-3.

Table 4-3         Action and Limit Levels for Air Quality Monitoring for all Stations

Monitoring Station

Action Level (mg /m3)

Limit Level (mg/m3)

1-hour TSP

24-hour TSP

1-hour TSP

24-hour TSP

A4

275

142

500

260

A7

274

141

500

260

Note:    1-hour & 24-hour TSP Action Level = (Baseline × 1.3 + Limit level)/2

 

4.3              Results of Noise Monitoring

4.3.1                 The baseline noise monitoring at noise monitoring locations N1, N2a, N3a and N4 was undertaken on 7 June 2017 to 23 June 2017.  Since there was continuous rain during daytime on 17 June 2017, the scheduled noise monitoring on 17 June 2017 at all stations were cancelled and baseline period would be extended one day.  Furthermore, in view of the unstable weather condition on 12 & 13 June 2017, two additional days of baseline monitoring were conducted in order to collect a comprehensive background noise level data.  Hence, the whole baseline noise monitoring was carried out from 7 June 2017 to 16 June 2017 and 18 June 2017 to 23 June 2017. The measurement data are shown in Appendix I and summarized in Table 4-4. 

Table 4-4         Summaries of Noise Monitoring Results

Monitoring Station

Normal day (Monday to Saturday):

Daytime 0700-1900, Leq(30min)

Public Holiday or Sunday:

Daytime 0700-1900, Leq(15min)

Mean

Min

Max

Mean

Min

Max

N1

63

58

70

63

60

66

N2a

58

55

62

57

57

57

N3a

57

54

64

58

57

59

N4

59

57

64

63

61

64

Note:  

(1)     Sound level meter set at N1 and N3a are made free-field measurement, façade correction (+3dB(A)) has added according to acoustical principles and EPD guidelines.

(2)     Figures refer to the measurement recorded at the designated station during the entire baseline period for general reference.

 

4.3.2                 The collected baseline noise monitoring data can represent the background condition of monitoring locations without the impact arising from construction of the project.  It therefore served as reference data to compare with the impact monitoring data in order to facilitate the investigation when Limit Level exceedance is triggered during the construction phase of the project.

 

Action/Limit Levels for Noise

4.3.3                 The Action and Limit Levels for construction noise are shown in Table 4-5.

Table 4-5         Action and Limit Levels of Construction Noise Monitoring

Time Period

Action Level

Limit Level in dB(A)

0700-1900 hours on normal weekdays

When one documented complaint is received

75 dB(A)

 


 

4.4              Discussion and Recommendations

Air Quality

Possible Influence of Seasonal Changes

4.4.1                 The baseline monitoring was conducted between 7 June 2017 and 23 June 2017 during typical Hong Kong wet seasons.  The baseline data so collected therefore represent the baseline air quality of the wet season immediately prior to commencement of the Project.  They may not reflect the air quality conditions of dry seasons in Hong Kong, which are normally significantly different.

 

4.4.2                 It is therefore recommended that the interpretation of the air quality monitoring data should take into account the influence of the seasonal changes, and the baseline conditions should be regularly reviewed, in particular during seasonal changes.

 

 


5                             Conclusions and Recommentations

5.1              Conclusions

5.1.1                 The baseline monitoring program was carried out during the period between 7 June 2017 and 23 June 2017 at the proposed monitoring locations by the ET according to the approved EM&A Manual.  During the baseline monitoring, there were no construction activities undertaken under this Project.

 

5.1.2                 Based on the baseline monitoring results, the recommended environmental performance criteria for air quality and construction noise are summarized as follows:

 

Recommended Action & Limit Levels of Air Quality

Monitoring Station

Action Level (mg /m3)

Limit Level (mg/m3)

1-hour TSP

24-hour TSP

1-hour TSP

24-hour TSP

A4

275

142

500

260

A7

274

141

500

260

 

Recommended Action & Limit Levels of Construction Noise

Monitoring Location

Action Level

Limit Level

0700-1900 hours on normal weekdays

N1, N2a, N3a & N4

When one or more documented complaints are received

75 dB(A)

 

5.2              Recommendations