4                         WATER QUALITY

 

4.1                    Introduction

4.1.1.1        With proper mitigation measures in place as recommended in the EIA report, adverse water quality would not be anticipated to the Water Sensitive Receivers (WSRs) as shown in Figure 4.1 during the construction and operation phases of this Project.  As such, regular inspections of construction activities and works sites and works areas should be conducted to ensure that the recommended mitigation measures are properly implemented.   

4.2                    Water Sensitive Receivers

4.2.1.1        The study area for the water quality impact assessment is delineated to be within 300m from the proposed Project site, which would cover the relevant existing and potential water sensitive receivers (WSRs) within approximately 5km from the Project site in the Eastern Buffer WCZ and detailed in Table 4.1 below.  Due to the highly urbanised nature of the Eastern District of Hong Kong Island, there are no natural streams located within 300m from the Project site.  There are, also, no marine biological sensitive receivers, such as shellfish culture grounds, marine park/reserves or commercial fishing grounds identified within the Eastern Buffer WCZ.  However, some seawater abstraction points for flushing (Sai Wan Ho, Siu Sai Wan) and cooling (WSR2: Pamela Youde Nethersole Eastern Hospital) have also been identified adjacent to the Project site as.

Table 4.1         Water Sensitive Receivers within Eastern Buffer WCZ

WSR No.

Descriptions

WSR1

WSD Water Flushing Intake – Sai Wan Ho

WSR2

Shau Kei Wan Typhoon Shelter

WSR3

Cooling Water Intake – Pamela Youde Nethersole Eastern Hospital

WSR4

Chai Wan Typhoon Shelter

WSR5

WSD Water Flushing Intake – Siu Sai Wan

WSR6

Cape Collinson – Corals

WSR7

Joss House Bay – Corals

WSR8

Tung Lung Chau West – Corals

WSR9

Tung Lung Chau Fish Culture Zone

WSR10

Tung Lung Chau North – Corals

WSR11

Tung Lung Chau South – Corals

 

4.3                    Monitoring Requirements

4.3.1              Construction Phase

4.3.1.1        No surface water quality monitoring would be required during the construction phase.  To avoid any potential water quality impacts arising from the construction activities, regular site audits should be conducted to ensure the recommended mitigation measures are properly implemented.

4.3.2              Operational Phase

4.3.2.1        No adverse water quality impact would be anticipated during the operational phase, provided that all mitigation measures recommended in the EIA report are properly implemented.  Therefore, water quality monitoring and auditing are not required during the operational phase.

4.4                    Mitigation Measures

4.4.1.1        The recommended mitigation measures for water quality impacts are presented the EMIS in Appendix 1.1 of this EM&A Manual.  In the event of complaints or non-compliances, the ET, Engineer and Contractor should review the effectiveness of these mitigation measures, design alternatives or additional mitigation measures as appropriate.  The Contractor should propose the corrective action to the Engineer for approval, and implement them accordingly.

4.5                    Audit Requirements

4.5.1              Background

4.5.1.1        The implementation of regular site audits aims to ensure the mitigation measures recommended in the EIA report to be properly undertaken during the construction phase of this Project.  It can also provide an effective control of any mal-practices and, therefore, achieve the continual improvement of the environmental performance on-site.  Site audits should include both site inspections and compliance audits.

4.5.2              Site Inspection

4.5.2.1        Inspections of the construction activities and works sites and works areas should be conducted by the Contractor at least on a weekly basis to ensure the mitigation measures to be properly implemented.

4.5.2.2        Site audits should be carried out by the Engineer, ET and Contractor, and should be based on the mitigation measures for the water pollution control as recommended in Appendix 1.1.  In the event that the recommended mitigation measures are not fully or properly implemented, the Contractor should report the deficiency to the Engineer and ET.  The appropriate action will need to be taken by the Contractor:

·               Investigate the problems and causes;

·               Discuss a remedial and corrective proposal with the ER and ET;

·               Take action according to the action notes agreed with the ER;

·               Implement the remedial and corrective action immediately;

·               Re-inspect the site conditions upon the completion of the remedial and corrective action; and

·               Record the event.

4.5.3              Compliance Audits

4.5.3.1        Compliance audits are to be undertaken by the Engineer and ET and escorted by the Contractor to ensure that a valid discharge license has been issued by the EPD prior to the discharge of the effluent from the construction activities of this Project site.  Monitoring of the quality of the treated effluent from the works areas should be carried out in accordance with the Water Pollution Control Ordinance (WPCO) license.  The audit results reflect whether the effluent quality is in compliance with the discharge license requirements.  In case of non-compliances, the following action should be taken:

·               The Contractor should notify the Engineer, ET and IEC;

·               The Engineer, ET and IEC should identify the sources of pollution and recommend and agree the appropriate mitigation measures for the Contractor;

·               The Engineer and ET should check the implementation status of the agreed mitigation measures by the Contractor;

·               The ET should increase the monitoring frequency until the effluent quality is in compliance with the requirements of the discharge license; and

·               The ET should record the non-compliances and propose preventive measures.