Central Reclamation, Phase III

Environmental Monitoring & Audit

Monthly Report No. 16

November 2004

 

 


Client   

Civil Engineering and Development Department
Hong Kong Island and Islands Development Office

Project   

Supplementary Agreement No. 3 to Agreement No. CE 15/94
Central Reclamation, Phase III

Design and Construction for the Minimum Option

Report No.

3128-REP-193-00

Copy No.

Date of Issue

10 December 2004

File Ref.   L:\S-proj\CR3\CR3.NEW\3128\              Reports\0193.doc

Report Title

 

Central Reclamation, Phase III

Environmental Monitoring & Audit

Monthly Report No. 16 - November 2004

 

 

Name

Sign

Date

Prepared by :

Albert Chan, ACL - Environmental Consultant

 

10 Dec. 2004

Reviewed by :

Susana Bezy, ACL – ET Leader

 

10 Dec. 2004

Authorised by :

Jon Varndell, ACL – Project Mgr

 

10 Dec. 2004

 

 

 

Distribution

 

 

Copy No

Issue to

Attention

Corr. Ref.

1

CEDD

Mr H H Yeung

3128/M45/200/OC6722/al

2, 3

EPD

Mr M W Ho

3128/M45/200/OC6722/al

4

EPD (LCO)

Mr Allan Hung

3128/M45/200/OC6722/al

5

Leighton-China State-Van Oord JV

Mr Malcolm Plummer

3128/M45/200/OC6722/al

6

CRIII Sites/PRE

Mr Douglas Miller

3128/M45/200/OC6722/al

7

Independent Checker (Environment)

Mr Bill Douglas

3128/M45/200/OC6722/al

8

Environmental Team Leader

Ms Susana Bezy

3128/M45/200/OC6722/al

9

Office Copy

 

 

 


1.           INTRODUCTION

1.1         Basic Project Information

2.           Environmental Status

2.1         Works Undertaken

2.2         Environmental Permits

2.3         Environmental Document Submission

2.4         Environmental Meetings

2.5         Environmental Monitoring Locations

3.           EM&A Requirements

3.1         Summary of Impact EM&A Requirements

3.2         Environmental Quality Performance Limits

3.3         Event Action Plan

3.4         Implementation of Environmental Measures

4.           Monitoring Results

4.1         Impact Monitoring Schedule in November 2004

4.2         Monitoring Methodology

4.3         Monitoring Equipment

4.4         Impact Monitoring Results

5.           Environmental Complaint and Non-Compliance

5.1         Environmental Exceedances

5.2         Environmental Complaint and Prosecution

5.3         Environmental Enquiries

6.           Forecast and Schedule

6.1         Key Works for the Coming Month

6.2         Monitoring Schedules for the Coming Months

6.3         Construction Programme for the Next 3 Months

7.           Conclusion

 


List of Annexes

Annex A              Project Organisation / Contact Information

Annex B              Contractor’s Work Programme

Annex C              Location of Monitoring Stations & Outfalls

Annex D             Environmental Quality Performance Limits for Air, Noise and Water Quality

Annex E               Event and Action Plan for Air, Noise and Water Quality

Annex F               Noise Monitoring Results

Annex G             Graphical Representation of Noise Monitoring Results

Annex H             Water Quality Monitoring Results

Annex I               Graphical Representation of Water Quality Monitoring Results

Annex J               Water Quality Exceedance Review

Annex K              IEC Site Inspection Report

 

List of Tables

Table 2.1 - Summary of the Environmental License / Permit Status

Table 2.2 - Summary of the Contractor's Environmental Related Document Submissions to the Engineer’s Representatives (ER).............................................................................................................................

Table 2.3 - Summary of Environmental Certification Sheet Submissions to the Environmental Protection Department (EPD)...................................................................................................................................

Table 3.1 - Summary of Impact EM&A Requirements

Table 4.1 - Water Quality Monitoring Programme (Seawater Intakes Stations)

Table 4.2  - Equipment for Air Quality Monitoring

Table 4.3 - Noise Monitoring Equipment

Table 4.4 - Equipment Used for Marine Water Quality Monitoring

Table 4.5 - Equipment Calibration Frequencies

Table 4.5 - Summary of Mid-Ebb Results for Marine-Based Stations

Table 4.6 - Summary of Mid-Flood Results for Marine-Based Stations

Table 4.7 - Summary of Mid-Ebb Results for Seawater Intake Stations

Table 4.8 - Summary of Mid-Flood Results for Seawater Intake Stations

Table 5.1 - Summary of Environmental Site Inspections

Table 6.1 - Water Quality Monitoring Programme

 

 

 

 


ACL

Atkins China Limited

CEDD

Civil Engineering and Development Department

CRIII

Central Reclamation Phase III

EIA

Environmental Impact Assessment

EIAO

Environmental Impact Assessment Ordinance

EM&A

Environmental Monitoring and Audit

EPD

Environmental Protection Department

ER

Engineer’s Representatives

ET

Environmental Team

IEC

Independent Environmental Checker

LCSD

Leisure and Cultural Services Department

LCSVO-JV

Leighton China State Van Oord Joint Venture

TDD

Territory Development Department

TSP

Total Suspended Particulates

WMP

Waste Management Plan

 


Executive Summary

The Central Reclamation Phase III (CRIII) Works, Contract No. HK 12/02, was awarded to Leighton China State Van Oord Joint Venture (LCSVO-JV) by the Territory Development Department (now called the Civil Engineering and Development Department (CEDD) after the merger of the Civil Engineering Department and the Territory Development Department on 1 July 2004), Hong Kong Islands and Islands Development Office.  The works under the Contract HK 12/02 commenced on 28 February 2003.  Contract HK 16/03 for the CRIII Hinterland Drainage Improvement Works was awarded to Wang Kee Construction Co. Ltd. and works for this contract commenced on 17 December 2003.

Atkins China Limited (ACL) has been appointed by CEDD to implement the Environmental Monitoring and Audit (EM&A) programme that was identified in the EIA Report for the CRIII Project and is providing Environmental Team (ET) services during the duration of the construction works.

This is the sixteenth Monthly EM&A Report under the EIAO for the works specified in Section 1.3 of the CRIII EIA Report.  This report summarises the monitoring results and audit findings of the EM&A programme during the reporting period from 1 to 30 November 2004.

Environmental Monitoring and Audit Progress

The monthly EM&A programme was undertaken in accordance with the EM&A Manual.  A summary of the monitoring activities performed in this reporting month is listed below:

·         Environmental site inspections were undertaken on 4, 11, 18 and 25 November 2004.

·         Noise monitoring was performed continuously for 24 hours.  However, noise measurements are unavailable for the period between 24 November and 28 November 2004 due to external renovation works at City Hall, which caused power disruptions to the noise meter.

·         Water quality monitoring was undertaken on the following days:

-          1 November 2004

-          3 November 2004

-          5 November 2004

-          8 November 2004

-          10 November 2004

-          12 November 2004

-          15 November 2004

-          17 November 2004

-          19 November 2004

-          22 November 2004

-          24 November 2004

-          26 November 2004

-          29 November 2004

Exceedance of Action and Limit Levels

There was no environmental air quality monitoring required during the reporting period.

Noise quality exceedances were recorded on 19, 21, 22, 23, 29 and 30 November 2004.  However, investigations into these exceedances found that they were not due to the project works.  The noise levels were attributable to exterior renovation works being carried out for City Hall by external contractors.  Communications with the building management for City Hall noted that the renovation works are expected to continue until mid-December 2004.  Further, there are currently no project works located in the vicinity of City Hall.

From the analysis of water quality monitoring results collected during the reporting period, exceedances of the Action and Limit Levels were found on several occasions.  Although DO levels below the Action Level were observed at seawater intake and marine-based stations, investigations found that they were due to natural variation or changes in ambient conditions and not caused by the project marine works.  It was noted that when the DO Action and/or Limit Levels were exceeded at the marine-based stations the control stations recorded similar DO levels.

Elevated concentrations of SS were recorded on 1, 12, 15, 19, 24, 26 and 29 November 2004.  These exceedances were investigated and were found to be attributable to poor ambient conditions and/or influences not related to project works.  The investigations generally found no significant gradient effects between those stations close to the project works and those more remote to the works area. 

Complaint Log

No environmental complaints were received during the reporting period.

Notifications of Summons and Prosecutions

There were no notifications of summons or prosecutions received with regard to the environment during this reporting period.

Site Inspection and Audit

Environmental site inspections for the CRIII project works area were undertaken on 4, 11, 18 and 25 November 2004.  A joint inspection was carried out with the IEC on 18 November 2004.


Key Works for the Coming Month

Future key works are as follows:

·         Placing of rock fill and temporary seawall construction at IRAW;

·         Sand filling work at IRAW;

·         In-situ work for the pumping stations installed at IRAW;

·         Trimming to rock mound works at IRAE;

·         Substructure works for the CTB;

·         Superstructure and architectural works for Pier No. 7;

·         Cooling watermains work; and

·         Maintenance and necessary repair works for seawater intake silt screens.


1.                INTRODUCTION

1.1              Basic Project Information

The Territory Development Department (now called the Civil Engineering and Development Department (CEDD) after the merger of the Civil Engineering Department and the Territory Development Department on 1 July 2004) of Hong Kong Special Administrative Region (HKSAR) is constructing the Central Reclamation Phase III Project (CRIII). 

The Main Works Contract HK 12/02 for CRIII commenced on 28th February 2003. Leighton-China State-Van Oord Joint Venture (LCSVO-JV) was awarded the Contract No. HK 12/02 for the construction of the CRIII Engineering Works.  Contract HK 16/03 for the CRIII Hinterland Drainage Improvement Works was awarded to Wang Kee Construction Co. Ltd. and works for this contract commenced on 17 December 2003. 

Atkins China Limited (ACL) has been commissioned by TDD (now called CEDD) to undertake the environmental monitoring and audit work for the project in accordance with the Environmental Permit (EP No. EP-122/2002) issued to TDD on 7 March 2002.  The CRIII Project Organisation is shown in Annex A.

This is the sixteenth monthly EM&A Report under the EIAO, which presents the results of EM&A work conducted during the period from 1 to 30 November 2004, inclusive.


2.                 Environmental Status

2.1              Works Undertaken

The works undertaken during the reporting month include obstruction clearing for marine piles, ballast to installed caissons at IRAW, rock filling works behind installed caissons, seawall block installations, placing of armour rock and levelling stone works, dredging, surcharge material works, landside cooling watermains works, substructure works for the Central Terminal Building (CTB) and maintenance and necessary repair work for seawater intake silt screens.

2.2              Environmental Permits

A summary of the status of all environmental permits, license, and/or notification to EPD for this project during the reporting period are presented in Table 2.1.

 Table 2.1 - Summary of the Environmental License / Permit Status

 

 

Item

Item Description

Date of Application

Permit Status

1

Application for a Permit to Dump Material (Category M & H Sediment) at Sea Under the Dumping at Sea Ordinance - ASMD Service Report for 21637V (Ref. H2189/U2c/10550/ MP/EY/ST/ec)

10 November 2004

-

2

Application for Renewal of Construction Noise Permit (GW-TS0189-04) for Grouting Works for Pre-bored H-pile (Ref. H2189/U2c/10459/MP/DC/CKA/ST/ec)

8 November 2004

-

3

LCSVO-JV submitted an Application for Renewal of Construction Noise Permit (GW-TS03318-04) for Night-time works at Man Yiu Street (Ref. H2189/U2c/10426/AT/ DC/ST/ec).

3 November 2004

-

 

2.3              Environmental Document Submission

A summary of the status of the submissions provided during the reporting month is presented in Table 2.2.

Table 2.2 - Summary of the Contractor's Environmental Related Document Submissions to the Engineer’s Representatives (ER)

 

 


 

Item

Document Title

Version

Date of Submission to ER

1

Advance Notification of Night-time Construction Work at PLA (Ref. H2189/C1/10693/MP/EY/DC/CKA/ST/atm)

-

22 November 2004

2

New Construction Noise Permit GW-RS0549-04 (Ref. H2189/C1/10692/MP/EY/ST/atm)

-

22 November 2004

3

New Construction Noise Permit GW-RS0541-04 (Ref. H2189/C1/10683/MP/EY/ST/ec)

-

20 November 2004

4

New Marine Dumping Permits EP/MD/05-083 (Ref. H2189/C1/10609/MP/EY/ST/atm)

-

15 November 2004

5

New Construction Noise Permit GW-RS0500-04 (Ref.

-

5 November 2004

 

A summary of the Environmental Certification Sheet submissions to EPD during the reporting month is presented in Table 2.3. 

Table 2.3 - Summary of Environmental Certification Sheet Submissions to the Environmental Protection Department (EPD)

 

 

 

No

Certification Subject

Letter Ref.

Date of Submission to EPD

Approved Status

1

Certification of Monthly Environmental Report No. 15  - October 2004

3128/M45/200/OC6611/SB/ AC/al

15 November 2004

-

 

2.4              Environmental Meetings

A brief environmental meeting was held with the Contractor on 25 November 2004 to discuss the details of the proposed silt curtain for sand filling works at IRAW.  The RE is currently reviewing other aspects of the sand filling proposal.

2.5              Environmental Monitoring Locations

The environmental monitoring locations are provided in Annex C.

 


3.                EM&A Requirements

3.1              Summary of Impact EM&A Requirements

The EM&A programme requires environmental monitoring for air quality, noise, water quality, waste management and landscape and visual aspects as specified in the CRIII Project EIA.  The EM&A requirements for each issue area are described in subsequent sections including:

·         All required monitoring parameters;

·         Action and Limit Levels; and

·         Event-Action Plans.

A summary of impact EM&A requirements is presented in Table 3.1.

 

Table 3.1 - Summary of Impact EM&A Requirements

 

 

Parameters

Descriptions

Locations

Frequencies

Duration

TSP

24-Hour TSP

2 Locations

Once every 6 days

During dust generating construction works

1-Hour TSP

2 Locations

Three times in every 6 days

During dust generating construction works

Noise

Leq (30 mins), L10, L90,

1 Location

Continuous measurements

Two weeks before Construction and During Construction

Water Quality

Dissolved Oxygen;

Salinity;

Temp;

Suspended Solids;

Turbidity.

14 Locations

3 times a week, Mid-ebb/flood tides

During Marine Works

Waste

On-Site Waste Audit

Active Work Sites

Periodically

During Construction

On-Site Waste Inspection

Landscape and Visual

Audits to ensure effective implementation of mitigation measures

During Construction

General Site Conditions

Environmental Site Inspection

Works areas and areas affected by works

Periodically

During Construction

 


3.2              Environmental Quality Performance Limits

Environmental Quality Performance Limits for air, noise and water quality as provided in the Baseline Monitoring Report (Final) are shown in Annex D.

3.3              Event Action Plan

The Event Action Plans for air, noise and water quality as provided in the Baseline Monitoring Report (Final) are shown in Annex E.

3.4              Implementation of Environmental Measures

The Contractor is required to implement mitigation measures listed in the EIA Report, EM&A Manual and Further Environmental Permit.  During routine site inspections, the Contractor's implementation of mitigation measures is reviewed.  With regard to mitigation measures for water quality, the Contractor has installed frame type silt curtains for rock filling works to reduce SS dispersion.  Further, the Contractor carried out daily visual inspection of the silt screens for seawater intakes.  Floating debris in the project area was collected at least once everyday and in the water body near cooling water intakes debris was collected at least three times a day.  Bi-weekly diving inspections for the silt screens were also carried out during the reporting month.


4.                Monitoring Results

4.1              Impact Monitoring Schedule in November 2004

Regular site inspections were carried out to assess whether the project's environmental protection and pollution control measures are in compliance with the contract specifications.  Inspections were conducted on 4, 11, 18 and 25 November 2004.

Air quality monitoring has not commenced yet as no significant work areas or construction activities with the potential to impact air quality are within range of the closest air quality sensitive receivers (ASR).

Continuous 24-hour noise monitoring was conducted during this reporting period.

Impact water quality monitoring at all monitoring stations was undertaken during this reporting month.  The water quality monitoring schedule for November 2004 is presented in Table 4.1.

Table 4.1 - Water Quality Monitoring Programme (Seawater Intakes Stations)

 

 

Date of Sampling

Tidal State

Timing of Sampling

1 November 2004

Mid Ebb

12:48  - 15:26

Mid Flood

08:28 - 11:30

3 November 2004

Mid Ebb

06:06 - 09:24

Mid Flood

13:30 - 16:15

5 November 2004

Mid Ebb

07:48 - 10:45

Mid Flood

15:22 - 18:08

8 November 2004

Mid Ebb

07:44 - 10:52

Mid Flood

14:14 - 16:54

10 November 2004

Mid Ebb

09:13 - 12:06

Mid Flood

15:13 - 17:48

12 November 2004

Mid Ebb

11:02 - 13:41

Mid Flood

15:13 - 17:54

15 November 2004

Mid Ebb

12:27 - 15:10

Mid Flood

07:52 - 11:03

17 November 2004

Mid Ebb

14:00 - 16:36

Mid Flood

09:45 - 12:34

19 November 2004

Mid Ebb

07:45 - 10:36

Mid Flood

15:12 - 17:59

22 November 2004

Mid Ebb

08:00 - 11:04

Mid Flood

14:11 - 16:45

24 November 2004

Mid Ebb

09:42 - 12:26

Mid Flood

15:00 - 17:37

26 November 2004

Mid Ebb

10:43 - 13:28

Mid Flood

15:23 - 18:07

29 November 2004

Mid Ebb

12:28 - 15:18

Mid Flood

07:08 - 11:05

4.2              Monitoring Methodology

4.2.1        Air Quality Monitoring

Air quality monitoring will be performed in accordance with the methodology described in the EM&A Manual once construction activities requiring air quality monitoring commence.  The locations of the monitoring stations at City Hall and PLA Headquarters are shown in Annex C.

4.2.2        Noise Quality Monitoring

Continuous 24-hour noise monitoring was performed in accordance with the methodology described in the EM&A Manual in the reporting period. The location of the noise monitoring station at City Hall is shown in Annex C.

4.2.3        Water Quality Monitoring

Water quality monitoring was performed in accordance with the methodology described in the EM&A Manual.  Monitoring for the reporting month was conducted at all stations, which comprises of 6 marine-based stations and 8 seawater intake stations.  The locations of the monitoring stations are shown in Annex C.

4.3              Monitoring Equipment

4.3.1        Air Quality

The equipment that is used for air quality monitoring is listed in Table 4.2.

Table 4.2  - Equipment for Air Quality Monitoring

 

 

Parameter Measured

Equipment

24-Hour Sampling

High Volume Sampler Model GS2310 by Anderson Instruments to be used for both monitoring stations.

1-Hour Sampling

MicroDust pro Aerosol Monitoring System to be used for both monitoring locations.

4.3.2        Noise Quality

The equipment used for continuous noise quality monitoring is listed in Table 4.3.

Table 4.3 - Noise Monitoring Equipment

 

 

Equipment

Model

Integrated Sound Level Meter (SLM)

B&K 2238

Calibrator

B&K 4231, Class 1

4.3.3        Water Quality

The equipment that was used for water quality monitoring is listed in Table 4.4.

 

Table 4.4 - Equipment Used for Marine Water Quality Monitoring

 

 

Parameter Measured

Equipment

Dissolved Oxygen and Temperature Measuring Equipment

A Dissolved Oxygen meter YSI model 58 was used.

·         This instrument was portable and weatherproof and used a DC power source.  The equipment was capable of measuring:

·         DO levels in the range of 0-20 mg/l and 0-200% saturation; and

·         Temperature of between 0 - 45 degree Celsius.

·         The equipment had a membrane electrode with an automatic temperature compensation complete with a cable. In addition, a Wirling Psychrometer was used as a reference thermometer during the sampling.

Turbidity Measurement Instrument

A Turbidimeter, HACH model 2100P was used for determining turbidity levels.  The instrument is portable and weatherproof and uses a DC power source. The instrument includes a photoelectric sensor capable of measuring turbidity between 0-1000 NTU.

PH

A MP125 pH Meter from Mettler Toledo was used to measure pH.

Salinity / Conductivity Meter

A Salinity / Conductivity meter YSI model 63 and model 30 was used for determining salinity concentrations.

Sample Containers and Storage

Water samples for SS analysis were stored in high density polythene bottles with no preservative added, packed in ice and delivered to the laboratory, and analysed as soon as possible after collection.

4.3.4        Equipment Calibration

The calibration frequencies of the monitoring equipment are provided in Table 4.5.

Table 4.5 - Equipment Calibration Frequencies

 

 

Equipment

Calibration Frequency

Latest Calibration Date

Dissolved Oxygen Meter

Every 6 months

26 October 2004

Turbidimeter

Every 3 months for secondary standards; meter is calibrated prior to each measurement to the secondary standards

26 October 2004

pH Meter

Prior to each sampling day

-

Pyschrometer

Every 6 months

5 October 2004

Integrated SLM

Every year

20 August 2004

4.4              Impact Monitoring Results

4.4.1        Air Quality & Noise Monitoring Results

No air quality monitoring work was undertaken during the reporting period as no significantly dusty construction activities with the potential to impact air quality are within range of the closest air quality sensitive receivers.

Noise quality monitoring work was undertaken during the reporting period.  The noise monitoring results are provided in Annex F.  Graphical representation of the noise monitoring data is provided in Annex G.

4.4.2        Water Quality Monitoring Results

Water quality monitoring was undertaken at all water quality monitoring locations during the reporting period.  The water quality monitoring results from this reporting period are presented in Annex H.  Graphical representation of the water quality data is provided in Annex I.  Summaries of the results are provided in Tables 4.5 to 4.9.

Marine-Based Stations

Monitoring stations M8 and M10 were selected as the marine-based impact stations as they are located outside the predicted influence of the dredging and reclamation works.  The detection of water quality degradation at these two stations may indicate that project marine works are adversely affecting water quality in Victoria Harbour.  Stations M7 and M9 are within the expected influence of the reclamation activities and are located along the works area boundary (or extent of the predicted sediment plume).  As such, M7 and M9 are used as indicator stations to note any significant elevations in SS, turbidity or reductions in DO that may affect the marine-based impact monitoring stations.

Table 4.5 is a summary of the marine-based stations monitoring results during mid-ebb tide.

 


Table 4.5 - Summary of Mid-Ebb Results for Marine-Based Stations

 


 

Station

 

Parameter

DO (S&M) mg/L

DO (B) mg/L

DO % Sat. (DA)

Turbidity (DA) NTU

SS (DA) mg/L

C1

min

4.7

4.6

65

3.7

6

max

5.5

5.2

76

7.3

9

avg

5.1

4.9

71

5.4

7

sd

0.2

0.2

3

1.1

1

C2

min

4.7

4.7

65

3.6

4

max

5.5

5.1

76

7.0

11

avg

5.1

4.9

71

5.2

7

sd

0.2

0.1

3

1.4

2

M7

min

4.5

4.5

62

3.6

5

max

5.6

5.2

78

9.5

10

avg

4.9

4.8

69

5.4

7

sd

0.3

0.2

4

1.6

2

M8

min

4.5

4.3

63

3.9

5

max

5.5

5.3

78

7.8

9

avg

5.0

5.0

71

5.7

7

sd

0.3

0.3

4

1.6

1

M9

min

4.6

4.4

64

3.9

5

max

5.4

5.1

76

10.2

11

avg

4.9

4.8

69

5.7

8

sd

0.2

0.2

3

1.8

2

M10

min

4.6

4.6

64

3.7

5

max

5.5

5.2

78

6.7

9

avg

5.1

5.0

72

5.4

7

sd

0.3

0.2

4

1.1

1

 

As Table 4.5 shows, DO levels at marine-based impact stations (M8 & M10) in the surface to middle layer during mid-ebb survey ranged between 4.3 and 5.5 mg/L with an average value of 5.0 mg/L and DO measurements in the bottom layer ranged from 4.3 to 5.3 mg/L with an average level of 5.0 mg/L.  Similar DO levels were recorded at the control stations at which DO levels in the surface to middle layer during mid-ebb survey ranged from 4.7 to 5.5 mg/L with an average value of around 5.1 mg/L; DO measurements in the bottom layer ranged between 4.6 and 5.2 mg/L with an average level of 4.9 mg/L. 

SS levels during mid-ebb tide ranged from 5 to 9 mg/L with an average value of 7 mg/L at the marine-based impact stations (M8 & M10), which is comparable to results from the control stations in which SS content ranged from 4 to 11 mg/L with an average of 7 mg/L.  Generally, the results showed no clear gradient effect (high SS and low DO levels from near-field stations M7 and M9 to far-field stations M8 and M10), which indicates that marine works are not adversely affecting marine water quality outside the work site boundary in Victoria Harbour.  Marine water quality at impact monitoring stations was found to be similar to that at the control stations also indicating that project marine works were generally not adversely affecting water quality in Victoria Harbour.

Table 4.6 is a summary of monitoring results from marine-based stations during mid-flood tide.


Table 4.6 - Summary of Mid-Flood Results for Marine-Based Stations

 

 

Station

 

Parameter

DO (S&M) mg/L

DO (B) mg/L

DO % Sat. (DA)

Turbidity (DA) NTU

SS (DA) mg/L

C1

min

4.6

4.5

65

3.9

6

max

5.8

5.1

80

7.3

9

avg

5.1

4.9

72

5.8

7

sd

0.3

0.2

4

1.2

1

C2

min

4.7

4.6

65

3.5

5

max

5.7

5.0

79

7.0

9

avg

5.1

4.8

71

5.1

7

sd

0.3

0.2

4

1.1

1

M7

min

4.3

4.2

60

3.9

5

max

5.5

5.4

79

8.5

9

avg

4.8

4.7

68

5.9

7

sd

0.3

0.3

5

1.3

1

M8

min

4.7

4.6

65

3.8

5

max

5.8

5.7

82

7.6

10

avg

5.1

5.0

72

5.5

7

sd

0.4

0.3

5

1.2

2

M9

min

4.4

4.4

62

4.3

5

max

5.7

5.4

80

7.8

9

avg

4.9

4.8

69

5.9

7

sd

0.3

0.3

5

1.2

1

M10

min

4.7

4.6

65

3.8

6

max

5.9

5.7

84

7.5

9

avg

5.2

5.0

72

5.8

7

sd

0.4

0.3

5

1.2

1

 

During mid-flood tide, DO levels at marine-based impact stations (M8 & M10) in the surface to middle layer ranged from 4.7 to 5.9 mg/L with an average level of 5.1 mg/L while DO values in the bottom layer ranged between 4.6 and 5.7 mg/L with an average of 5.0 mg/L.  Similar DO concentrations were recorded at the control stations in the surface to middle layer during mid-flood survey ranged between 4.6 and 5.8 mg/L with an average value of 5.1 mg/L and DO results in the bottom layer ranged from 4.5 and 5.1 mg/L with an average of 4.9 mg/L. 

SS content ranged between 5 and 10 mg/L (for stations M8 & M10) with an average of 7 mg/L during mid-flood tide and ranged from 5 to 9 mg/L with an average value of 7 mg/L at the control stations.  Again, the results showed no clear gradient effect and no significant difference between control stations and marine-based impact stations.  Therefore, the marine-based station results indicate that during the reporting month the dredging works were not adversely affecting water quality outside the work site boundary.

Seawater Intake Stations

Table 4.7 is a summary of monitoring results from seawater intake stations during mid-ebb tide.


Table 4.7 - Summary of Mid-Ebb Results for Seawater Intake Stations

 

 

Station

 

Parameter

DO mg/L

DO % Sat.

Turbidity NTU

SS mg/L

M1

min

4.0

58

5.6

8

max

6.0

85

10.1

12

avg

4.6

65

7.5

9

sd

0.5

7

1.5

1

M2

min

3.6

51

5.2

8

max

5.1

73

10.5

17

avg

4.3

60

7.6

11

sd

0.4

6

1.5

2

M3

min

3.6

52

4.2

7

max

4.9

70

11.0

13

avg

4.2

60

6.9

10

sd

0.4

6

2.1

2

M4

min

4.0

59

4.0

6

max

5.0

71

9.3

12

avg

4.5

64

5.9

8

sd

0.3

4

1.7

2

M5

min

4.0

58

4.3

7

max

5.4

77

9.1

11

avg

4.6

66

6.4

9

sd

0.4

6

1.4

1

M6

min

3.8

55

3.8

7

max

5.4

76

8.4

11

avg

4.5

64

6.2

8

sd

3.8

55

3.8

7

M11

min

4.0

58

5.4

7

max

5.3

75

9.7

12

avg

4.5

65

7.5

9

sd

0.4

5

1.5

1

M12

min

4.0

57

4.3

6

max

5.1

71

9.0

12

avg

4.4

63

6.4

8

sd

0.3

5

1.5

2

 


Seawater intake results during mid-ebb tide, Table 4.7, show that DO levels ranged from 3.6 to 6.0 mg/L with an average of 4.4 mg/L.  SS ranged between 6 and 17 mg/L with an average value of 10 mg/L.  Low DO levels at the intake stations were recorded during the reporting month but investigations found that they were not due to project works.  Elevated SS levels were found on 1, 12 and 19 November 2004.  These levels were investigated and it was found that they were generally due to ambient conditions and/or influences not related to project works. 

Table 4.8 is a summary of monitoring results from seawater intake stations during mid-flood tide.


Table 4.8 - Summary of Mid-Flood Results for Seawater Intake Stations

 

 

Station

 

Parameter

DO mg/L

DO % Sat.

Turbidity NTU

SS mg/L

M1

min

3.9

54

5.1

7

max

5.8

83

10.1

14

avg

4.7

67

7.5

9

sd

3.9

54

5.1

7

M2

min

3.7

51

5.6

9

max

5.7

80

10.1

14

avg

4.3

61

7.9

12

sd

0.6

8

1.2

2

M3

min

3.8

51

4.8

8

max

4.8

69

8.8

13

avg

4.2

60

7.1

10

sd

0.3

5

1.2

2

M4

min

3.9

54

5.8

8

max

5.3

74

9.3

15

avg

4.5

64

7.2

11

sd

0.4

6

1.0

2

M5

min

3.8

55

4.8

7

max

5.2

73

9.2

13

avg

4.5

64

6.5

8

sd

0.5

6

1.2

2

M6

min

3.5

50

4.8

7

max

5.6

79

8.2

13

avg

4.5

64

6.5

9

sd

0.5

7

1.2

2

M11

min

4.1

57

4.8

6

max

5.4

79

9.8

13

avg

4.6

66

7.3

9

sd

0.4

5

1.3

2

M12

min

4.0

58

4.8

5

max

5.3

73

8.4

12

avg

4.6

65

6.5

9

sd

0.3

4

1.0

2

 

During mid-flood survey, Table 4.8 shows that DO levels at seawater intake stations ranged from 3.5 to 5.8 mg/L with an average of 4.5 mg/L.  SS ranged from 5 to 15 mg/L with an average SS content of 10 mg/L.  The above results show that water quality during mid-flood tide was also generally good.  Again, low DO levels were found but these were found to be not due to project works.  The elevated SS levels found on 1, 12, 15, 24, 26 and 29 November 2004 were investigated and were found that to be generally due to ambient conditions and/or influences not related to project works.

4.4.3        Waste Management

No waste management audit was scheduled within this reporting period.  The arrangement of waste management audit is detailed in the Waste Management Plan.

4.4.4        Landscape and Visual

As the major construction activities undertaken during the reporting month were related to marine works, the landscape and visual impacts are considered to be minimal.

 


5.                Environmental Complaint and Non-Compliance

5.1              Environmental Exceedances

The total number of exceedances for air, noise and water quality are presented in following sections.

5.1.1        Air Quality

No air quality monitoring work was undertaken during the reporting period. 

5.1.2        Noise Quality

Noise quality exceedances were recorded on 19, 21, 22, 23, 29 and 30 November 2004.  However, investigations into these exceedances found that they were not due to the project works.  The noise levels were attributable to exterior renovation works being carried out for City Hall by external contractors.  Communications with the building management for City Hall noted that the renovation works are expected to continue until mid-December 2004.  Further, there are currently no project works located in the vicinity of City Hall.

It should be noted that noise measurements are not available for the period between 24 November and 28 November 2004 as the external power source for the noise meter was disrupted due to the electrical and mechanical work carried out at City Hall.

5.1.3        Water Quality

During the reporting period, exceedances of the water quality criteria were generally found not to be caused by the project works.  Visual observations of the harbour during the reporting month noted the presence of floating debris throughout Victoria Harbour, including areas well beyond the project site.

Elevated concentrations of SS were recorded on 1, 12, 15, 19, 24, 26 and 29 November 2004.  These exceedances were investigated and were found to be attributable to poor ambient conditions and/or influences not related to project works.  The investigations generally found no significant gradient effects between those stations close to the project works and those more remote to the works area.  For example, station M12, which is located more than 1 km away from the works area, would record SS levels that are similar to those found at stations closer to the project works.

Additional SS monitoring was also conducted at Queensway Government Offices (QGO) outfall and Culvert J during the reporting month to observe the impacts from outfall discharges.  For the exceedance recorded on 1 November 2004, additional SS monitoring results indicated that the SS level at Culvert J was relatively high.  As such, elevated SS levels in the surrounding area (e.g. station M4) may have been significantly influenced by the discharges.

Although DO levels below the Action and Limit Levels were observed at the seawater intakes and marine-based stations, the investigations found that they were due to natural variation or changes in ambient conditions and not caused by the project marine works.  It was noted that when the DO Action and/or Limit Levels were exceeded at the marine-based stations the control stations recorded similar DO levels.  Further, the results generally do not show any significant gradient effect between stations close to the marine works and stations more remote to the works area. 

5.1.4        Waste Management

No non-compliances with regard to waste management were recorded in the reporting month.

5.1.5        Landscape and Visual

No non-compliance with regard to landscape and visual aspects were recorded in the reporting month.

5.1.6        Site Environmental Audit

No environmental non-compliances were found during environmental site inspections conducted during the reporting period.  A joint site inspection with the IEC was conducted on 18 November 2004, and the IEC's site inspection report is provided in Annex K.

A summary of the findings from the site inspections conducted during the reporting month is provided in Table 5.1.

 

Table 5.1 - Summary of Environmental Site Inspections

 

 

Date of Inspection

Observations

Action(s)

4 November 2004

No non-compliances found.

N/A

11 November 2004

Exposed soil surfaces at CR-10 appeared to be dry.

The Contractor was asked to spray the area with water to avoid dusty emissions.

A slightly yellowish silty discharge was observed flowing from Culvert J.

This discharge is from off-site and is not project related.

18 November 2004

Exposed soil surfaces at CR-10 appeared to be dry.

The Contractor was reminded again to spray the area with water to avoid dusty emissions.

A small gap was noticed in the silt curtain used for rock filling works.

The Contractor is reminded to properly maintain the silt curtain.

No significant sediment plumes were observed at the works area.

N/A

25 November 2004

The hose connections to the sedimentation tank at CR-10 were found to be leaky.

The Contractor was asked to tighten or repair the connections before continuing with sump pumping.

One earth stockpile at CR-10 was not entirely covered by impervious sheeting.

The Contractor was asked to fully cover all dusty stockpiles on site.

No toilet facilities for workers were found at CR-10.

It was suggested that the Contractor install additional toilet facilities at CR-10.

No significant sediment plumes were observed outside the works area.  However, yellowish water could be seen near the rock filing works within the boundaries of IRAW.

N/A

 

No significant sediment plumes were observed near the marine works during the site inspections.

5.2              Environmental Complaint and Prosecution

No environmental complaints and no prosecution notices or summons were received during the reporting month.

5.3              Environmental Enquiries

No environmental enquiries were received during the reporting month.

 


6.                Forecast and Schedule

6.1              Key Works for the Coming Month

The key issues to be considered in the coming month include the following:

·         Placing of rock fill and temporary seawall construction at IRAW;

·         Sand filling works at IRAW;

·         In-situ work for the pumping stations installed at IRAW;

·         Trimming to rock mound works at IRAE;

·         Substructure works for the CTB;

·         Superstructure and architectural works for Pier No. 7;

·         Cooling watermains work; and

·         Maintenance and necessary repair works for seawater intake silt screens.

6.2              Monitoring Schedules for the Coming Months

Based on the Contractor’s programme, the Environmental Monitoring Programme for the next three months is planned as follows:

TSP (24 hr and 1 hr monitoring)

Upon commencement of significant dust generating activities within range of the closest air quality sensitive receiver, dependent upon the Contractor’s programme.

Noise (Continuous Measurements)

The noise monitoring programme throughout the entire construction period is 24-hour continuous.

Water Quality Monitoring

The water quality monitoring schedule for the upcoming months is provided in the following table.

Table 6.1 - Water Quality Monitoring Programme

 

 

Date of Sampling

Sampling Time

1 December 2004

09:00

14:37

3 December 2004

08:00

15:48

6 December 2004

08:30

14:21

8 December 2004

08:57

15:14

10 December 2004

10:47

16:14

13 December 2004

08:30

14:00

15 December 2004

09:51

14:45

17 December 2004

11:41

16:52

20 December 2004

08:30

14:04

22 December 2004

09:11

15:15

24 December 2004

10:52

16:08

27 December 2004

12:00

17:00

29 December 2004

09:00

14:00

31 December 2004

10:00

15:00

3 January 2005

12:00

17:00

5 January 2005

08:30

13:29

7 January 2005

09:30

14:45

10 January 2005

12:00

17:00

12 January 2005

08:45

13:57

14 January 2005

10:08

15:34

17 January 2005

12:00

17:00

19 January 2005

08:30

13:30

21 January 2005

10:26

17:30

24 January 2005

11:52

16:41

26 January 2005

08:30

13:30

28 January 2005

08:49

14:05

31 January 2005

10:19

16:09

2 February 2005

11:28

17:00

4 February 2005

08:30

13:30

7 February 2005

11:27

16:13

14 February 2005

10:16

16:31

16 February 2005

11:31

18:57

18 February 2005

09:08

17:30

21 February 2005

11:14

15:53

23 February 2005

12:00

17:00

25 February 2005

08:30

13:30

28 February 2005

08:52

14:53

 

6.3               Construction Programme for the Next 3 Months

The construction programme for the next 3 months is provided in Annex B and will be updated by the Contractor. 

The ET will follow the Contractor’s proposed programme to ensure the compliance of environmental performance and proper implementation of all necessary mitigation measures.


7.                Conclusion

During the reporting period, exceedances of the water quality criteria occurred and most were found not to be caused by the project works.  The ambient water quality throughout Hong Kong waters was found to be relatively poor, with low DO levels and relatively high SS concentrations being recorded at the control stations on several occasions.  Visual observations of the harbour during the reporting month noted that the water throughout Victoria Harbour contained numerous amounts of floating debris, which are not originated from the project.

Low DO levels have been recorded at seawater intake and marine-based stations.  However, investigations into the DO exceedances found that the low levels were not due to project works as marine-based stations and control stations recorded similar levels.  Near-shore influences not related to project works might have affected DO concentrations at the seawater intake stations.

Elevated SS levels were recorded on several occasions during the month of November 2004.  Investigations into these exceedances found that they were attributed to ambient conditions and/or influences not related to project works.  The results generally did not show any significant gradient effects between stations located near the works and stations located farther away from the works.

The monitoring work for this reporting month has been independently verified by the Independent Environmental Checker (IEC) and has been found to be in compliance with the requirements of the EM&A programme.

Air Quality Action and Limit Levels for the City Hall Moni