1.1 The TPSTW is located within the Tai Po Industrial Estate. It currently comprises four Stages: I, II , IVA and IVB works. Stage I was completed in 1979 and has provided secondary treatment since then. In 1982, Drainage Services Department (DSD) carried out the Stage II extension, which consisted of the extension to the Stage I treatment facilities and the construction of sludge treatment facilities. Stage IVA and IVB works were two other extensions to the TPSTW at a site adjacent to Stage I/II works at 1986 and 1995 respectively, with an increased capacity of 54,400 m3/day. Stage I/II and Stage IV are designed to operate independently although they are interconnected in order to provide flexibility of operation.
1.2 The TPSTW - Stage V (hereinafter referred to as the Project) aims to upgrade the existing STW to provide additional sewage treatment capacity from the present design flow of 88,000 m3/day to 130,000 m3/day to meet the demands of both the existing and future developments, and to meet the revised discharge license requirements. The Project will be constructed within the existing TPSTW. Site layout plan of the Project is provided in Figure 1.1.
1.3 The Project is a Designated Project under the Environmental Impact Assessment Ordinance (EIAO).
1.4 The scope of the Project includes the expansion and modification of the existing Stage I/II works and Stage IV works of the STW to increase the total plant capacity from the present design flow of 88,000m3/day to 130,000m3/day, with a view to achieving the effluent quality as stated in Table 1.1. The Project will be implemented in 2 phases. The design capacities of Phase 1 and Phase 2 works are 100,000 m3/d and 130,000 m3/d respectively.
The key elements of the Phase 1 works include:
(a) Additional inlet and preliminary treatment works;
(b) Modification of existing secondary treatment process units (retrofit existing bioreactors and 2 new final clarifiers);
(c) Reconstruction of 6 existing final clarifiers;
(d) Additional sludge treatment facilities; and
(e) Ancillary works to existing treatment facilities.
The key elements of the Phase 2 work include:
(a) Construction of additional secondary treatment process units (1 primary clarifier, 3 bioreactors and 2 final clarifiers);
(b) Reconstruction of 4 existing final clarifiers;
(c) Disinfection facilities;
(d) Additional sludge treatment facilities; and
(e) Ancillary works to existing treatment facilities.
Table 1.1 Current and new effluent standards upon commissioning
|
Parameters |
Current Standards |
New Standards |
||||
|
95 percentile |
Maximum |
95 percentile |
Maximum |
Annual Average |
Monthly Geometric Mean |
|
|
BOD5 (mg/l) |
20 |
40 |
20 |
40 |
- |
- |
|
TSS (mg/l) |
30 |
60 |
30 |
60 |
- |
- |
|
Total N (mg/l) |
25 |
50 |
- |
35 |
20 |
- |
|
NH3-N (mg/l) |
- |
- |
- |
10 |
5 |
- |
|
E.coli (counts/100ml) |
- |
- |
15,000 |
- |
- |
1,000 |
1.5 The construction of Phase 1 works is scheduled to commence in 2005 for completion in 2009 whilst the Phase 2 works, being subject to actual flow build-up, is scheduled to commission before 2016.
1.6 The purpose of this Environmental Monitoring and Audit (EM&A) Manual is to guide the set up of an EM&A programme to ensure compliance with the Environmental Impact Assessment (EIA) study recommendations, to assess the effectiveness of the recommended mitigation measures and to identify any further need for additional mitigation measures or remedial actions. This Manual outlines the monitoring and audit programme for the construction and operational phase of the Project. It aims to provide systematic procedures for monitoring, auditing and minimising environmental impacts associated with construction works and operational activities.
1.7 Hong Kong environmental regulations and the Hong Kong Planning Standards and Guidelines have served as environmental standards and guidelines in the preparation of this Manual. In addition, the EM&A Manual has been prepared in accordance with the requirements stipulated in Annex 21 of the Technical Memorandum on the EIA Process (EIAO-TM).
1.8 This Manual contains the following information:
· responsibilities of the Contractor, the Engineer or Engineer’s Representative (ER), Environmental Team (ET) and Independent Checker (Environment) (IC(E)) with respect to the environmental monitoring and audit requirements during the course of the Project;
· project organisation for the Project;
· the basis for, and description of the broad approach underlying the EM&A programme;
· requirements with respect to the construction programme schedule and the necessary environmental monitoring and audit programme to track the varying environmental impact;
· details of the methodologies to be adopted, including all field laboratories and analytical procedures, and details on quality assurance and quality control programme;
· the rationale on which the environmental monitoring data will be evaluated and interpreted;
· definition of Action and Limit Levels (A/L levels);
· establishment of Event and Action Plans (EAP);
· requirements for reviewing pollution sources and working procedures required in the event of non-compliance with the environmental criteria and complaints;
· requirements for presentation of environmental monitoring and audit data and appropriate reporting procedures; and
· requirements for review of EIA predictions and the effectiveness of the mitigation measures / environmental management systems and the EM&A programme.
1.9 For the purpose of this manual, the ET leader, who shall be responsible for and in charge of the ET, shall refer to the person delegated the role of executing the EM&A requirements.
1.10 The roles and responsibilities of the various parties involved in the construction phase EM&A process and the organisational structure of the organisations responsible for implementing the EM&A programme are outlined below. The proposed project organisations and lines of communication during construction and operational phases with respect to environmental protection works are shown in Figures 1.2 & 1.3 respectively.
The Contractor shall report to the Engineer. The duties and responsibilities of the Contractor are:
· employ an Environmental Team (ET) to undertake monitoring, laboratory analysis and reporting of environmental monitoring and audit;
· provide assistance to ET in carrying out monitoring;
· submit proposals on mitigation measures in case of exceedances of Action and Limit levels in accordance with the Event and Action Plans;
· implement measures to reduce impact where Action and Limit levels are exceeded;
· implement the corrective actions instructed by the Engineer;
· accompany joint site inspection undertaken by the ET; and
· adhere to the procedures for carrying out complaint investigation.
The ET shall report to the Contractor. The ET Leader and the ET shall be employed to conduct the EM&A programme and ensure the Contractor’s compliance with the project’s environmental performance requirements during construction. The ET Leader shall be an independent party from the Contractor and have relevant professional qualifications, or have sufficient relevant EM&A experience subject to approval of the ER and the EPD. The duties and responsibilities of the ET are:
· monitor various environmental parameters as required in this EM&A Manual;
· analyse the environmental monitoring and audit data and review the success of EM&A programme to cost-effectively confirm the adequacy of mitigation measures implemented and the validity of the EIA predictions and to identify any adverse environmental impacts arising;
· carry out regular site inspection to investigate and audit the Contractors' site practice, equipment and work methodologies with respect to pollution control and environmental mitigation, and effect proactive action to pre-empt problems;
· audit and prepare audit reports on the environmental monitoring data and site environmental conditions;
· report on the environmental monitoring and audit results to the IC(E), Contractor, the ER and EPD or its delegated representative;
· recommend suitable mitigation measures to the Contractor in the case of exceedance of Action and Limit levels in accordance with the Event and Action Plans; and
· adhere to the procedures for carrying out complaint investigation.
The ET shall be led and managed by the ET leader. The ET leader shall possess at least 10 years experience in EM&A and/or environmental management.
The Engineer is responsible for overseeing the construction works and ensuring that they are undertaken by the Contractor in accordance with the specification and contractual requirements. The duties and responsibilities of the Engineer are:
· supervise the Contractor’s activities and ensure that the requirements in the EM&A Manual are fully complied with;
· inform the Contractor when action is required to reduce impacts in accordance with the Event and Action Plans;
· employ an IC(E) to audit the results of the EM&A works carried out by the ET;
· participate joint site inspection undertaken by the ET; and
· adhere to the procedures for carrying out complaint investigation.
The Independent Checker (Environment) shall advise the Engineer’s Representative on environmental issues related to the project. The duties and responsibilities of the IC(E) are:
· review the EM&A works performed by the ET (at least at monthly intervals);
· audit the monitoring activities and results (at least at monthly intervals);
· review the EM&A reports submitted by the ET;
· review the proposal on mitigation measures submitted by the Contractor in accordance with the Event and Action Plans; and
· adhere to the procedures for carrying out complaint investigation.
The IC(E) shall have project management experience in addition to the requirements of the ET leader stated above.
Sufficient and suitably qualified professional and technical staff shall be employed by the respective parties to ensure full compliance with their duties and responsibilities, as required under the EM&A programme for the duration of the Project.