Environmental Impact Assessment Ordinance (Cap. 499), Section 5(7)

Environmental Impact Assessment Study Brief No. ESB-124/2005

Project Title: Relocation of Yiu Lian Floating Dock No. 3

(hereinafter known as the “Project”)

Name of Applicant: Yiu Lian Dockyards Ltd.

(hereinafter known as the “Applicant”)

1. BACKGROUND

1.1 An application (No. ESB-124/2005) for an Environmental Impact Assessment (EIA) study brief under section 5(1) of the Environmental Impact Assessment Ordinance (EIAO) was submitted by the Applicant on 24 January 2005 with a Project Profile (No. PP-239/2005).

1.2 The proposed Project is to decommission the Yiu Lian Floating Dock No. 3 (the Dock) at the Yam O Wan of North Lantau (North Lantau), and to construct and operate the Dock at a proposed location at the South-west coast of Tsing Yi (Tsing Yi) after relocation. As given in the Project Profile, the Dock has a pontoon length of about 287m and breadth of 55m and has been operating at North Lantau for a substantial period of time since late 80s. Present and proposed locations of the Dock at Lantau and Tsing Yi are shown respectively in Figures 1 and 2 (as modified from the plans in the Project Profile ref: PP-239/2005). Key elements of the Project are to:

(i) Decommission the Dock at North Lantau, and

(ii) Construct and operate the Dock at Tsing Yi.

1.3 Pursuant to section 5(7)(a) of the EIAO, the Director of Environmental Protection (the Director) issues this EIA study brief to the Applicant to carry out an EIA study.

1.4 The purpose of this EIA study is to provide information on the nature and extent of environmental impacts arising from the Project and related activities taking place concurrently. This information will contribute to decisions by the Director on:

(i) the overall acceptability of any adverse environmental consequences that are likely to arise as a result of the Project;

(ii) the conditions and requirements for the Project to mitigate against adverse environmental consequences wherever practicable; and

(iii) the acceptability of residual impacts after the proposed mitigation measures are implemented.

2. OBJECTIVES OF THE EIA STUDY

2.1 The objectives of the EIA study are as follows:

(i) to describe the Project and associated works together with the requirements for carrying out the Project;

(ii) to identify and describe the elements of the community and environment likely to be affected by the Project and/or likely to cause adverse impacts to the Project, including natural and man-made environment and the associated environmental constraints;

(iii) to identify potential Tributyltin (TBT) and heavy metal contamination in marine sediments due to operation of the Dock in Lantau and ways to minimise and mitigate the impacts;

(iv) to identify and quantify emission sources and determine the significance of impacts on sensitive receivers and potential affected uses including those along the Sham Tseng coast, especially in respect of marine water and sediment quality impacts;

(v) to identify mitigation measures for the proposed Dock at Tsing Yi with regard to the risk incidence associated with the Caltex and ExxonMobil West terminals at South-west Tsing Yi;

(vi) to propose the provision of mitigation measures so as to minimize pollution, environmental disturbance and nuisance arising from the Project;

(vii) to investigate the feasibility, practicability, effectiveness and implications of the proposed mitigation measures;

(viii) to identify, predict and evaluate the residual environmental impacts (i.e. after practicable mitigation) and the cumulative effects expected to arise from the Project in relation to the sensitive receivers and potential affected uses;

(ix) to identify, assess and specify methods, measures and standards, to be included in the detailed design, decommissioning, construction and operation stage of the Project which are necessary to mitigate these environmental impacts and reduce them to acceptable levels;

(x) to investigate the extent of the secondary environmental impacts that may arise from the proposed mitigation measures and to identify constraints associated with the mitigation measures in the EIA study, as well as the provision of any necessary mitigation measures;

(xi) to identify constraints associated with the mitigation measures recommended in the EIA study; and

(xii) to design and specify the environmental monitoring and audit requirements to ensure the effective implementation of the environmental protection and pollution control measures.

3. DETAILED REQUIREMENTS OF THE EIA STUDY

The Purpose

3.1 The purpose of this study brief is to scope the key issues of the EIA study and to specify the environmental issues that are required to be reviewed and assessed in the EIA report. The Applicant has to demonstrate in the EIA report that the criteria in the relevant sections of the Technical Memorandum on the Environmental Impact Assessment Process of the Environmental Impact Assessment Ordinance (hereinafter known as the “TM”) are fully complied with.

The Scope

3.2 The scope of this EIA study shall cover the Project proposed in the Project Profile and works mentioned in section 1.2 above. The EIA study shall address the key issues described below, together with any other key issues identified during the course of the EIA study, and the cumulative environmental impacts of the Project, through interaction or in combination with other existing, committed, planned and known potential development in the vicinity of the Project. Key issues include, amongst others:

Decommissioning of the Dock at North Lantau

(a) the potential TBT and heavy metal contaminated marine sediments caused by operation of the Dock at Lantau and their handling/treatment method(s);

(b) the potential water quality impacts caused by decommissioning activities, especially when potentially contaminated sediments are disturbed during handling/treatment process;

Construction and Operation of the Dock at Tsing Yi

(d) practicable means to implement and audit the Applicant’s proposal in section 3.2.2.1 of the Project Profile with regard to receiving ships without TBT containing paints during operation stage of the Dock, and

(e) the potential operational water quality impacts from wastewater of the Project that might contain anti-fouling chemicals or TBT, where applicable.

3.3 Notwithstanding that the study brief has scoped the key issues for assessment, to facilitate public inspection, the EIA shall cover information presented in the Project Profile together with necessary updates, and explain why no adverse impacts are anticipated in certain areas or issues covered by the TM.

3.4 Consideration of Alternative Options and Methods in Decommissioning, Construction and Operation

3.4.1 Proposed site at Tsing Yi

i) The Applicant shall present considerations for the proposed project siting, and the history of the Project.

3.4.2 Consideration of Alternative Options and Methods for the Project

Decommissioning of the Dock at North Lantau

i) Where the EIA predicts/identifies TBT and heavy metal contamination in marine sediments caused by operation of the Dock, the Applicant shall consider different handling/treatment methods for the contamination. With a view to proposing the best practicable means, a comparison shall be made with regard to environmental benefits and dis-benefits of different approaches to handle/treat the contaminated sediments. The approaches can include, among others, “Leave the sediments in place”, “In-situ or Ex-site treatment” or disposal as a last resort;

ii) Where dredging/disturbance of the TBT and heavy metal contaminated marine sediments are unavoidable especially during sediments handling and/or anchor removal, the Applicant shall explore alternative construction methods in order to minimize adverse water quality impacts;

Construction and Operation of the Dock at Tsing Yi

iii) Where the EIA predicts adverse water quality impacts during construction stage, the Applicant shall explore alternative construction methods and sequences of works, and

iv) Where the EIA predicts adverse direct/cumulative water quality and sediment deposits impacts to sensitive receivers (including those along the Sham Tseng coast) from wastewater discharge of the Dock, the Applicant shall consider, among others, alternative wastewater treatment methods, discharge locations, work modes, mooring location and layout in order to avoid and minimize adverse environmental impacts during operation stage to the maximum practicable extent.

3.5 Technical Requirements

The Applicant shall conduct the EIA study to address the environmental aspects of the works and activities as described in the scope set out above. The EIA study shall include the following technical requirements on specific impacts unless otherwise approved by the Director specifically in writing.

3.5.1 Water Quality Impact

3.5.1.1 The Applicant shall follow the criteria and guidelines for evaluating and assessing water pollution as stated in Annexes 6 and 14 of the TM respectively for the Project.

3.5.1.2 The study area for the purpose of this water quality impact assessment shall cover relevant sensitive receivers that have a bearing on the environmental acceptability of the Project within the North Western Water Control Zone, Western Buffer Water Control Zone and part of the Southern Water Control Zone north of Hei Ling Chau. Sensitive receivers include beaches along the Sham Tseng coast.

3.5.1.3 The Applicant shall identify and analyse in the assessment respective physical, chemical and biological disruptions of marine water and sediments arising from the Project.

3.5.1.4 The applicant shall include the following in the water quality impact assessment:

General

⁽ⁱ⁾^{collection and review of background
information on the existing and planned water system(s) and sensitive receivers
which might be affected by the Project;}

⁽ⁱⁱ⁾^{characterization of water quality and
sediment quality on the respective water system(s) and sensitive receivers
which might be potentially affected by the Project based on existing
information or site surveys/tests as appropriate;}

⁽ⁱⁱⁱ⁾^{identification and analysis of existing
and planned future activities (such as respective floating docks operating at
Tsing Yi); beneficial uses related to the water system(s) and water sensitive
receivers;}

^(iv)^{identification of pertinent water
quality and sediments objectives and establishment of other appropriate water
and sediments quality criteria or standards for the water system(s) and
sensitive receivers as identified above;}

^(v)^{establishment of an emission inventory
on the quantities and}^{characteristics
of pollution sources arising from the Project;}

^(vi)^{prediction of impacts on the water
system(s) and sensitive receivers due to those alterations and changes, and the
pollution sources identified above. The prediction shall include different activities
and sequences of the Project;}

^(vii)^{assessment of cumulative impacts due to
relevant concurrent and planned projects, activities or pollution sources within
the identified water system(s). In particular, the cumulative impacts due to
other floating docks moored at Tsing Yi shall be assessed during the operation
stage;}

^{Impact prediction for decommissioning works at Yam O
Wan}

^(viii)^{identification and quantification of dredging,
filling and disposal activities together with any proposed fill source and
disposal ground. Characterization of marine sediments and mobilization of any contaminants
through field investigation, sampling, and chemical laboratory tests including
chemical screening for those contaminants listed in Appendix B. The Applicant
should submit a plan for the Director’s agreement with regard to the range of
investigation parameters; the number, type, location and methods of sampling;
sample preservation, and chemical laboratory test method/protocols;}

^(ix)^{prediction and quantification of impacts
on water system(s) and aquatic lifes due to the presence of contaminated sediments
based on the chemical screening above. Possible impacts include the effect on
benthic organism, aquatic organisms and marine mammal at organismic and
ecosystem levels. The Applicant should submit a plan for the Director’s
agreement with regard to the study methodology, testing and analysis such as
sediment biological toxicity test, bioaccumulation test, sampling and chemical
testing of the water column;}

^(x)^{evaluation and comparison of alternative
handling and treatment methods for the contaminated sediments in accordance
with contaminants investigation results in section ix in order to mitigate the
impacts to within acceptable limits. These alternatives shall include the “Leave
the sediments in place”, “In-situ or Ex-situ treatment” and “Disposal” options.
The comparison of different options should comprise at least assessment of the
associated environmental impacts and identification of any residual
environmental impact;}

^(xi)^{simulation and quantification of degree
of mobilization of various contaminants during decommissioning stage by
Elutriate tests (USACE) if marine sediments are found to be contaminated.
Prediction and quantification of impacts associated with the proposed
handling/treatment method above where adverse impacts are anticipated. The possible
impacts include changes in sediment erosion or deposition, water and sediment
quality and the effect on the aquatic organism due to such activities. The Applicant shall seek the Director’s
agreement whether a mathematical modeling
or other technique should be applied to quantify the impacts. Where a
mathematical modeling is necessary to predict and quantify the impacts, the
model shall comply with the specifications listed in Appendix C;}

^{Impact prediction during construction stage at Tsing Yi}

^(xii)^{identification and quantification of
dredging, filling, and disposal activities during the construction stage.
Characterization of marine sediments and mobilization of any contaminants through
field investigation, sampling, and chemical laboratory tests including chemical
screening for those contaminants listed in Appendix B. The Applicant should submit
a plan for the Director’s agreement including the range of investigation
parameters to be analyzed; the number, type, location and methods of sampling;
sample preservation and chemical laboratory test method/protocols;}

^(xiii)^{simulation
and quantification of the degree of mobilization of various contaminants during
construction stage by Elutriate tests (USACE) if marine sediments are found to be contaminated. Prediction and
quantification of the marine water quality impacts by techniques approved by
the Director where adverse impacts are anticipated. Possible impacts include
changes in sediment erosion or deposition, water and sediment quality and the
effect on the aquatic organism due to such activities;}

^{Impact prediction during operation stage at Tsing Yi}

^(xiv)^{identification of any physical changes due
to operation of the Dock at Tsing Yi;}

^(xv)^{identification and quantification of pollution
including existing and likely future water pollution sources. The potential
contaminants shall include those caused by ship servicing, in particular due to
hull washing and sand blasting of exterior hull surface. An emission inventory
on the quantities and characteristics of existing and future pollution sources
shall be provided with a view of assessing the cumulative effect. Field
investigation and laboratory tests shall be conducted as appropriate;}

^(xvi)^{conduct of a literature /desktop review
to identify different types of non-TBT paints commonly used on the market and
identification of their characteristics and impacts on the environment arising
from ship servicing activities, because the project profile specifies that the
Dock will only receive ships using non-TBT containing paint;}

^(xvii)^{prediction and quantification, by
mathematical modeling or other technique approved by the Director, of impacts
on water system(s) and sensitive receivers, especially those along the Sham
Tseng coast, due to alterations and changes and the pollution sources
identified. Possible impacts include changes in sediment erosion or deposition,
water and sediment quality, the effect on the aquatic organisms and any
potential impact on sensitive uses. The mathematical model shall comply with
the specifications listed in Appendix C;}

^Mitigation

^(xviii)^{proposal to avoid or minimize the
adverse impact identified above, in particular suitable handling method for
potentially contaminated sediments and/or their disposal in the decommissioning and construction stages;}

^(xix)^{proposal of water pollution prevention
and mitigation measures to be implemented for the Project so as to reduce the
water quality, sediment quality and ecological impacts to within acceptable
standards. Best management
practices to reduce waste-water, and non-point source pollution shall be
investigated and proposed as appropriate;}

^(xx)^{proposal of practical and effective
mitigation measures to be implemented for the Dock at Tsing Yi with regard to:}

^(a)^{the
audit of proposal to receive ships without TBT containing paint, and}

^(b)^{management
of waste-water from ship-servicing activities that might contain potentially
contaminated sediments, and}

^(xxi)^{evaluation and quantification of
residual impacts on the water system(s) and the sensitive receivers with regard
to the appropriate water and sediment quality criteria, standards and
guidelines.}

3.5.2 Waste Management Implications

3.5.2.1 The Applicant shall follow the criteria and guidelines for evaluating and assessing waste management implications as stated in Annexes 7 and 15 of the TM respectively.

3.5.2.2 The assessment of waste management implications shall cover the followings :

(i) Analysis of Activities and Waste Generation

The Applicant shall identify the quantity, quality and timing of the waste arising from the Project, based on the sequence and duration of these activities of the Project.

(ii) Proposal for Waste Management

(a) Prior to consideration of disposal options for various types of wastes, the Applicant shall evaluate opportunities for reducing waste generation and on-site or off-site reuse. Measures should be considered separately for planning/design and decommissioning/construction stage respectively to include proposals for design modification and measures for maximizing waste reduction.

(b) After taking into account of opportunities for reducing waste generation and maximizing reuse, the Applicant shall estimate the types and quantities of the wastes that require disposal, and describe the disposal options for each type of waste in detail. The disposal options for each type of wastes shall take into account of the assessment in section (c) below.

(c) An assessment shall be carried out for the impact associated with waste handling (including labelling, packaging & storage), collection, treatment, transportation and disposal of wastes, together with proposal of mitigation measures, where appropriate. The assessment should at least cover potential hazard, air and odour emission, wastewater discharge, and transportation risk.

3.5.3 Hazard Assessment for the Dock at Tsing Yi

3.5.3.1 The proposed dock will be within consultation zone of the Potentially Hazardous Installation of the Caltex Terminal and Exxon Mobil West Terminals at Tsing Yi, the Application shall provide an assessment/review for risk incidence and propose necessary mitigation measures, including, among others, an evacuation plan.

3.5.4. Air Quality Assessment during Operation Stage at Tsing Yi

3.5.4.1 The Applicant shall provide a breakdown of the average fuel consumption per day of the Dock. Based on the fuel consumption rate, and in the event that air pollutant emissions from the Dock have potential to cause non-compliance of the criteria in section 1 of Annex 4 in the TM at affected Air Sensitive Receivers, assessment shall be carried out to confirm environmental acceptability of the Project following Appendix D.

3.5.5 Summary of Environmental Outcomes

3.5.5.1 The EIA report shall contain a summary of the key environmental outcomes arising from the EIA study, including the population and environmentally sensitive areas protected, environmentally friendly designs recommended, key environmental problems avoided, compensation areas included and the environmental benefits of environmental protection measures recommended.

3.5.6 Environmental Monitoring and Audit (EM&A) Requirements

3.5.6.1 The Applicant shall identify and justify in the EIA study whether there is any need for EM&A and/or environmental management system (EMS) activities during the decommissioning, construction and operation of the Dock and, if affirmative to define the scope of the EM&A requirements for the Project in the EIA study.

3.5.6.2 Subject to the confirmation of EIA findings, the Applicant shall comply with the requirements as stipulated in Annex 21 of the TM. The Applicant shall also propose real-time reporting of monitoring data for the Project through a dedicated internet website.

3.5.6.3 The Applicant shall prepare a project implementation schedule (in the form of a checklist as shown in Appendix A to this EIA study brief or otherwise as approved by the Director) containing all the EIA recommendations and mitigation measures with reference to the implementation programme.

4. DURATION OF VALIDITY

The EIA Study Brief is valid for 36 months from the date of issue. If the EIA study does not commence within this period, the Applicant shall apply to the Director for a fresh EIA study brief before commencement of the EIA study.

5. REPORT REQUIREMENTS

5.1 In preparing the EIA report, the Applicant shall refer to Annex 11 of the TM for the contents of an EIA report. The Applicant shall also refer to Annex 20 of the TM, which stipulates the guidelines for the review of an EIA report.

5.2 The Applicant shall supply the Director with the following number of copies of the EIA report and the executive summary:

(i) 50 copies of the EIA report in English and 80 copies of the executive summary (each bilingual in both English and Chinese) as required under section 6(2) of the EIAO to be supplied at the time of application for approval of the EIA report.

(ii) where necessary, addendum to the EIA report and the executive summary submitted in 5.2 (i) above as required under section 7(1) of the EIAO, to be supplied upon advice by the Director for public inspection.

(iii) 20 copies of the EIA report in English and 50 copies of the executive summary (each bilingual in both English and Chinese) with or without Addendum as required under section 7(5) of the EIAO, to be supplied upon advice by the Director for consultation with the Advisory Council on the Environment.

5.3 The Applicant shall, upon request, make additional copies of the above documents available to the public, subject to payment by the interested parties of full costs of printing.

5.4 In addition, to facilitate the public inspection of the EIA report via the EIAO internet website, the Applicant shall provide electronic copies of both the EIA report and the executive summary prepared in HyperText Markup Language (HTML) (version 4.0 or later) and in Portable Document Format (PDF version 4.0 or later), unless otherwise agreed by the Director. For the HTML version, a content page capable of providing hyperlink to each section and sub-section of the EIA report and the executive summary shall be included in the beginning of the document. Hyperlinks to all figures, drawings and tables in the EIA report and executive summary shall be provided in the main text from where the respective references are made. All graphics in the EIA report and/or executive summary shall be in interlaced GIF format unless otherwise agreed by the Director.

5.5 The electronic copies of the EIA report and the executive summary shall be submitted to the Director at the time of application for approval of the EIA report.

5.6 When the EIA report and the executive summary are made available for public inspection under section 7(1) of the EIA Ordinance, the content of the electronic copies of the EIA report and the executive summary must be the same as the hard copies and the Director shall be provided with the most updated electronic copies.

5.7 To promote environmentally friendly and efficient dissemination of information, both hard copies and electronic copies of EM&A reports recommended by the EIA study shall be required and their format shall be agreed by the Director.

6. OTHER PROCEDURAL REQUIREMENTS

6.1 During the EIA study, if there is any change in the name of Applicant for this EIA study brief, the Applicant must notify the Director immediately.

6.2 If there is any key change in the scope of the Project mentioned in section 1.2 of this EIA study brief, in Project Profile No. PP-239/2005 and affected sensitive receivers, the Applicant shall seek confirmation from the Director in writing on whether or not the scope of issues covered by this EIA study brief can still cover the key changes, and the additional issues, if any, that the EIA study shall also address. If the changes to the Project fundamentally alter the key scope of the EIA study brief, the Applicant shall apply to the Director for a fresh EIA study brief.

--- END OF EIA STUDY BRIEF ---

March 2005

Environmental Assessment and Noise Division,

Environmental Protection Department

Figure 2 : The Proposed Location of The Yiu Lian Floating Dock No. 3

( Plan modified from Figure 1-3 of Project Profile no. PP-239/2005, submitted on 24-1-2005 )

圖二 : 友聯3號浮船塢的計劃位置

( 平面圖修改自24-1-2005提交的工程項目簡介編號PP-239/2005圖1-3 )

Appendix A - Implementation Schedule for *Decommissioning /Construction

/Operation Phase

EIA Ref.	EM&A Ref.	Recommended Mitigation Measures	Objectives of the Recommended Measure & Main Concerns to address	Who to implement the measure	Location of the measure	When to implement the measure	What requirements or standards for the measure to achieve

*Please delete as appropriate

Appendix B - List of contaminants:

Metals: Cadmium

Chromium

Copper

Mercury

Nickel

Lead

Zinc

Metalloid: Arsenic

PAHs: Low molecular weight polychlorinated (PAHs)

High molecular weight PAHs

Total Polychlorinated biphenyls (PCBs)

Tributyltin (TBT)

Appendix C - Water Quality Modeling Requirements

Modelling software general

1. The modelling software shall be fully 3-dimensional capable of accurately simulating the stratified condition, salinity transport, and effects of wind and tide on the water body within the model area.

2. The modelling software shall consist of hydrodynamic, water quality, sediment transport and particle dispersion modules. The hydrodynamic, water quality and sediment transport modules shall have been proven with successful applications locally and overseas.

3. The hydrodynamic, water quality and sediment transport modules shall be strictly mass conserved at all levels.

Model details – Calibration & Validation

1. No field data collection is required for model calibration for this study. However, the models shall be properly calibrated and validated before its use in this study in the area including the North Western Water Control Zone, Western Buffer Water Control Zone and part of the Southern Water Control Zone north of Hei Ling Chau, with the field data collected by:

· Hydraulic and Water Quality Studies in Victoria Harbour (1987)

· Port and Airport Development Strategy - Enhancement of WAHMO Mathematical Models (1990)

· Strategic Sewage Disposal Scheme Stage II - Oceanic Outfall, Oceanographic Surveys and Modelling (1992)

· Update on Cumulative Water Quality and Hydrological Effect of Coastal Developments and Upgrading of Assessment Tool (1998)

· Environmental Protection Department (EPD)’s routine monitoring data

· Tidal data from Hong Kong Observatory, Macau and relevant Mainland Authorities

2. Tidal data shall be calibrated and validated in both frequency and time domain manner.

3. For the purpose of calibration and validation, the model shall run for not less than 15 days of real sequence of tide (excluding model spin up) in both dry and wet seasons with due consideration of the time required to establish initial conditions.

4. In general the hydrodynamic models shall be calibrated to the following criteria:

Criteria Level of fitness

with field data

· tidal elevation (rms) < 8 %

· maximum phase error at high water and low water < 20 minutes

· maximum current speed deviation < 30 %

· maximum phase error at peak speed < 20 minutes

· maximum direction error at peak speed < 15 degrees

· maximum salinity deviation < 2.5 ppt

Model details – Simulation

1. The water quality modelling results shall be qualitatively explainable, and any identifiable trend and variations in water quality shall be reproduced by the model. The water quality model shall be able to simulate the interaction of dissolved oxygen, phytoplankton, organic and inorganic nitrogen, phosphorus, silicate, BOD, temperature, suspended solids, contaminants release of dredged and disposed material, air-water exchange, E. coli and benthic processes. It shall also be able to simulate salinity. Salinity results simulated by hydrodynamic models and water quality models shall be demonstrated to be consistent.

2. The sediment transport module for assessing impacts of sediment loss due to marine works shall include the processes of settling, deposition and re-erosion. The values of the modelling parameters shall be agreed with the Director.

3. The models shall at least cover the Hong Kong waters, the Pearl Estuary and the Lema (Dangan) Channel to incorporate all major influences on hydrodynamic and water quality. A fine grid model can be used for detailed assessment of this study. It shall either be linked to the far field model or form part of the far field model by gradual grid refinement. The coverage of the proposed model shall be properly designed such that it is remote enough so that the boundary conditions would not be affected by the proposed project. The model coverage area shall be agreed with the Director. For indicative purpose, it shall cover the North Western Water Control Zone, Western Buffer Water Control Zone and part of the Southern Water Control Zone north of Hei Ling Chau.

4. In general, grid size at the area affected by the project shall be less than 400 m in open waters and less than 75 m around sensitive receivers. The grid schematization shall be agreed with the Director.

5. The assessment shall include the construction and operation phases of the project. Scenarios to be assessed shall cover different options proposed by the Applicant in order to quantify the environmental impacts and improvements from these options. Corresponding pollution load, bathymetry and coastline shall be adopted in the model set up.

6. Hydrodynamic, water quality, sediment transport and particle dispersion modules, where appropriate, shall be run for (with proper model spin up) at least a real sequence of 15 days spring-neap tidal cycle in both the dry season and the wet season.

7. The results shall be assessed for compliance of Water Quality Objectives. Any changes in hydrodynamic regime shall be assessed. Daily erosion / sedimentation rate shall be computed and its ecological impact shall be assessed.

8. The impact on relevant representing sensitive receivers shall be assessed.

9. Cumulative impacts due to other projects, activities or pollution sources within the Study Area to the agreement of Director shall also be predicted and quantified.

10. All modelling input data and results shall be submitted in digital media to the Director.

Appendix D– Technical Requirement for Air Quality Assessment during Operation Stage at Tsing Yi

1. Prior to the assessment, the Applicant shall provide a breakdown of the average daily fuel consumption of the Dock. Having regard to the fuel consumption rate, and in the event that air pollutant emissions have potential to cause non-compliance of the criteria in section 1 of Annex 4 in the TM at the Air Sensitive Receivers (ASRs), an air quality assessment shall be carried out to confirm the environmental acceptability of the Project.

2. The Applicant shall follow the criteria and guidelines for evaluating and assessing the air quality impact as stated in section 1 of Annex 4 and Annex 12 of the TM, respectively. The “Assessment Area” for air quality impacts shall be generally defined by a distance of 500m from the boundary of the Project site. The Applicant shall assess the air pollutant concentrations in accordance with the relevant sections of the guidelines in Appendixes D1, D2 to D3, or other methodology as agreed by the Director.

3. The air quality impact assessment shall include the following:

i) Background and Analysis of Activities - The Applicant shall provide background information of the Dock/plant and report the consideration/measures, where appropriate, that had been taken in the planning of the Project . With a view of abating air pollution impacts, alternative operation methods shall be reviewed to avoid and minimize the impacts.

ii) Identification of ASRs and Examination of Emission/Dispersion Characteristics – The Applicant shall identify and describe representative existing and planned/committed ASRs that would likely be affected by the Project. The assessment points of the identified ASRs should be such that they represent the worst impact point of these ASRs. A map showing the location and description including the name of the buildings, their uses and height of the selected assessment points shall be given.

iii) Quantitative Assessment Methodology - The Applicant shall apply the general principles in the modelling guidelines while making allowance for the specific characteristic of the Project. This specific methodology must be documented in such level of details (preferably with tables and diagrams) to allow readers of the assessment report to understand set-up of the model without referring to input files.

iv) Remedies and Mitigation Measures - The Applicant shall propose remedies and mitigation measures where the predicted air quality impact exceeds the criteria set in section 1 of Annex 4 in the TM. The Applicant shall demonstrate quantitatively that the mitigated impacts will comply with the criteria stipulated in section 1 of Annex 4 in the TM together with evaluation of residual impact, where necessary.

v) Submission of Electronic File - Input and output file(s) of the model run(s) shall be submitted to the Director in electronic format.

Appendix D1 - Guidelines on Choice of Models and Model Parameters

[The information contained in this Appendix is meant to assist the Applicant in performing the air quality assessment. The Applicant must exercise professional judgement in applying this general information.]

1. Introduction

1.1 To expedite the review process by the Authority and to assist project proponents or environmental consultants with the conduct of air quality modelling exercises which are frequently called for as part of environmental impact assessment studies, this paper describes the usage and requirements of a few commonly used air quality models.

2. Choice of models

2.1 The models which have been most commonly used in air quality impact assessments, due partly to their ease of use and partly to the quick turn-around time for results, are of Gaussian type and designed for use in simple terrain under uniform wind flow. There are circumstances when these models are not suitable for ambient concentration estimates and other types of models such as physical, numerical or mesoscale models will have to be used. In situations where topographic, terrain or obstruction effects are minimal between source and receptor, the following Gaussian models can be used to estimate the near-field impacts of a number of source types including dust, traffic and industrial emissions.

Model	Applications
FDM	for evaluating fugitive and open dust source impacts (point, line and area sources)
CALINE4	for evaluating mobile traffic emission impacts (line sources)
ISCST3	for evaluating industrial chimney releases as well as area and volumetric sources (point, area and volume sources); line sources can be approximated by a number of volume sources.

These frequently used models are also referred to as Schedule 1 models (see attached list).

2.2 Note that both FDM and CALINE4 have a height limit on elevated sources (20 m and 10m, respectively). Source of elevation above these limits will have to be modelled using the ISCST3 model or suitable alternative models. In using the latter, reference should be made to the 'Guidelines on the Use of Alternative Computer Models in Air Quality Assessment'.

2.3 The models can be used to estimate both short-term (hourly and daily average) and long-term (annual average) ambient concentrations of air pollutants. The model results, obtained using appropriate model parameters (refer to Section 3) and assumptions, allow direct comparison with the relevant air quality standards such as the Air Quality Objectives (AQOs) for the relevant pollutant and time averaging period.

3. Model input requirements

3.1 Meteorological Data

3.1.1 At least 1 year of recent meteorological data (including wind speed, wind direction, stability class, ambient temperature and mixing height) from a weather station either closest to or having similar characteristics as the study site should be used to determine the highest short-term (hourly, daily) and long-term (annual) impacts at identified air sensitive receivers in that period. The amount of valid data for the period should be no less than 90 percent.

3.1.2 Alternatively, the meteorological conditions as listed below can be used to examine the worst case short-term impacts:

Day time: stability class D; wind speed 1 m/s (at 10m height); worst-case wind angle; mixing height 500 m

Night time: stability class F; wind speed 1 m/s (at 10m height); worst case wind angle; mixing height 500 m

This is a common practice with using the CALINE4 model due to its inability to handle lengthy data set.

3.1.3 For situations where, for example, (i) the model (such as CALINE4) does not allow easy handling of one full year of meteorological data; or (ii) model run time is a concern, the followings can be adopted in order to determine the daily and annual average impacts:

(i) perform a frequency occurrence analysis of one year of meteorological data to determine the actual wind speed (to the nearest unit of m/s), wind direction (to the nearest 10^o) and stability (classes A to F) combinations and their frequency of occurrence;

(ii) determine the short term hourly impact under all of the identified wind speed, wind direction and stability combinations; and

(iii) apply the frequency data with the short term results to determine the long term (daily / annual) impacts.

Apart from the above, any alternative approach that will capture the worst possible impact values (both short term and long term) may also be considered.

3.1.4 Note that the anemometer height (relative to a datum same for the sources and receptors) at which wind speed measurements were taken at a selected station should be correctly entered in the model. These measuring positions can vary greatly from station to station and the vertical wind profile employed in the model can be grossly distorted from the real case if incorrect anemometer height is used. This will lead to unreliable concentration estimates.

3.1.5 An additional parameter, namely, the standard deviation of wind direction, σ_θ, needs to be provided as input to the CALINE4 model. Typical values of σ_θrange from 12^o for rural areas to 24^ofor highly urbanised areas under 'D' class stability. For semi-rural such as new development areas, 18^o is more appropriate under the same stability condition. The following reference can be consulted for typical ranges of standard deviation of wind direction under different stability categories and surface roughness conditions.

Ref.(1): Guideline On Air Quality Models (Revised), EPA-450/2-78-027R, United States Environmental Protection Agency, July 1986.

3.2 Emission Sources

All the identified sources relevant to a process plant or a study site should be entered in the model and the emission estimated based on emission factors compiled in the AP-42 (Ref. 2) or other suitable references. The relevant sections of AP-42 and any parameters or assumptions used in deriving the emission rates (in units g/s, g/s/m or g/s/m²) as required by the model should be clearly stated for verification. The physical dimensions, location, release height and any other emission characteristics such as efflux conditions and emission pattern of the sources input to the model should also correspond to site data. If the emission of a source varies with wind speed, the wind speed-dependent factor should be entered.

Ref.(2): Compilation of Air Pollutant Emission Factors, AP-42, 5thEdition, United States Environmental Protection Agency, January 1995.

3.3 Urban/Rural Classification

Emission sources may be located in a variety of settings. For modelling purposes these are classed as either rural or urban so as to reflect the enhanced mixing that occurs over urban areas due to the presence of buildings and urban heat effects. The selection of either rural or urban dispersion coefficients in a specific application should follow a land use classification procedure. If the land use types including industrial, commercial and residential uses account for 50% or more of an area within 3 km radius from the source, the site is classified as urban; otherwise, it is classed as rural.

3.4 Surface Roughness Height

This parameter is closely related to land use characteristics of a study area and associated with the roughness element height. As a first approximation, the surface roughness can be estimated as 3 to 10 percent of the average height of physical structures. Typical values used for urban and new development areas are 370 cm and 100 cm, respectively.

3.5 Receptors

These include discrete receptors representing all the identified air sensitive receivers at their appropriate locations and elevations and any other discrete or grid receptors for supplementary information. A receptor grid, whether Cartesian or Polar, may be used to generate results for contour outputs.

3.6 Particle Size Classes

In evaluating the impacts of dust-emitting activities, suitable dust size categories relevant to the dust sources concerned with reasonable breakdown in TSP (< 30 μgm) and RSP (< 10 μgm) compositions should be used.

3.7 NO₂ to NOx Ratio

The conversion of NOx to NO₂ is a result of a series of complex photochemical reactions and has implications on prediction of near field impacts of traffic emissions. Until further data are available, three approaches are currently acceptable in the determination of NO₂:

(a) Ambient Ratio Method (ARM) - assuming 20% of NOx to be NO₂; or

(b) Discrete Parcel Method (DPM, available in the CALINE4 model); or

(c) Ozone Limiting Method (OLM) - assuming the tailpipe NO₂ emission to be 7.5% of NOx and the background ozone concentration to be in the range of 57 to 68 μg/m³ depending on the land use type (see also EPD reference paper 'Guidelines on Assessing the 'TOTAL' Air Quality Impacts').

3.8 Odour Impact

In assessing odour impacts, a much shorter time-averaging period of 5 seconds is required due to the shorter exposure period tolerable by human receptors. Conversion of model computed hourly average results to 5-second values is therefore necessary to enable comparison against recommended standard. The hourly concentration is first converted to 3-minute average value according to a power law relationship which is stability dependent (Ref. 3) and a result of the statistical nature of atmospheric turbulence. Another conversion factor (10 for unstable conditions and 5 for neutral to stable conditions) is then applied to convert the 3-minute average to 5-second average (Ref. 4). In summary, to convert the hourly results to 5-second averages, the following factors can be applied:

Stability Category	1-hour to 5-sec Conversion Factor
A & B	45
C	27
D	9

Under 'D' class stability, the 5-second concentration is approximately 10 times the hourly average result. Note, however, that the combined use of such conversion factors together with the ISCST results may not be suitable for assessing the extreme close-up impacts of odour sources.

Ref.(3): Richard A. Duffee, Martha A. O' Brien and Ned Ostojic, 'Odor Modeling - Why and How', Recent Developments and Current Practices in Odor Regulations, Controls and Technology, Air & Waste Management Association, 1991.

Ref.(4): A.W.C. Keddie, 'Dispersion of Odours', Odour Control - A Concise Guide, Warren Spring Laboratory, 1980.

3.9 Plume Rise Options

The ISCST3 model provides by default a list of the U.S. regulatory options for concentration calculations. These are all applicable to the Hong Kong situations except for the 'Final Plume Rise' option. As the distance between sources and receptors are generally fairly close, the non-regulatory option of 'Gradual Plume Rise' should be used instead to give more accurate estimate of near-field impacts due to plume emission. However, the 'Final Plume Rise' option may still be used for assessing the impacts of distant sources.

3.10 Portal Emissions

These include traffic emissions from tunnel portals and any other similar openings and are generally modelled as volume sources according to the PIARC 91 (or more up-to-date version) recommendations (Ref. 5, section III.2). For emissions arising from underpasses or any horizontal openings of the like, these are treated as area or point sources depending on the source physical dimensions. In all these situations, the ISCST3 model or more sophisticated models will have to be used instead of the CALINE4 model. In the case of portal emissions with significant horizontal exit velocity which cannot be handled by the ISCST3 model, the impacts may be estimated by the TOP model (Ref. 6) or any other suitable models subject to prior agreement with EPD. The EPD's 'Guidelines on the Use of Alternative Computer Models in Air Quality Assessment' should also be referred to.

Ref.(5): XIXth World Road Congress Report, Permanent International Association of Road Congresses (PIARC), 1991.

Ref.(6): N. Ukegunchi, H. Okamoto and Y. Ide "Prediction of vehicular emission pollution around a tunnel mouth", Proceedings 4th International Clean Air Congress, pp. 205-207, Tokyo, 1977

3.11 Background Concentrations

Background concentrations are required to account for far-field sources which cannot be estimated by the model. These values, to be used in conjunction with model results for assessing the total impacts, should be based on long term average of monitoring data at location representative of the study site. Refer to EPD reference paper 'Guidelines on Assessing the 'TOTAL' Air Quality Impacts' for further information.

3.12 Output

The highest short-term and long-term averages of pollutant concentrations at prescribed receptor locations are output by the model and to be compared against the relevant air quality standards specified for the relevant pollutant. Contours of pollutant concentration are also required for indicating the general impacts of emissions over a study area.

Copies of model files in electronic format should also be provided for EPD's reference.

Schedule 1

Air Quality Models Generally Accepted by Hong Kong Environmental Protection Department For Regulatory Applications as at 1 July 1998*

Industrial Source Complex Dispersion Model - Short Term Version 3 (ISCST3) or the latest version developed by U.S. Environmental Protection Agency (USEPA)

California Line Source Dispersion Model Version 4 (CALINE4) or the latest version developed by Department of Transportation, State of California, U.S.A.

Fugitive Dust Model (FDM) or the latest version developed by USEPA.

* EPD is continually reviewing the latest development in air quality models and will update this Schedule accordingly.

Appendix D2 - Guidelines on Assessing the “Total” Air Quality Impacts

1. Total Impacts - 3 Major Contributions

1.1 In evaluating the air quality impacts of a proposed project upon air sensitive receivers, contributions from three classes of emission sources depending on their distance from the site should be considered. These are:

Primary contributions: project induced

Secondary contributions: pollutant-emitting activities in the immediate neighbourhood

Other contributions: pollution not accounted for by the previous two (Background contributions)

2. Nature of Emissions

2.1 Primary contributions

In most cases, the project-induced emissions are fairly well defined and quite often (but not necessarily) the major contributor to local air quality impacts. Examples include those due to traffic network, building or road construction projects.

2.2 Secondary contributions

Within the immediate neighbourhood of the project site, there are usually pollutant emitting activities contributing further to local air quality impacts. For most local scale projects, any emission sources in an area within 500m radius of the project site with notable impacts should be identified and included in an air quality assessment to cover the short-range contributions. In the exceptional cases where there is one or more significant sources nearby, the study area may have to be extended or alternative estimation approach employed to ensure these impacts are reasonably accounted for.

2.3 Background contributions

The above two types of emission contributions should account for, to a great extent, the air quality impacts upon local air sensitive receivers, which are often amenable to estimation by the 'Gaussian Dispersion' type of models. However, a background air quality level should be prescribed to indicate the baseline air quality in the region of the project site, which would account for any pollution not covered by the two preceding contributions. The emission sources contributing to the background air quality would be located further afield and not easy to identify. In addition, the transport mechanism by which pollutants are carried over long distances (ranging from 1km up to tens or hundreds of kms) is rather complex and cannot be adequately estimated by the 'Gaussian' type of models.

3. Background Air Quality - Estimation Approach

3.1 The approach

In view of the difficulties in estimating background air quality using the air quality models currently available, an alternative approach based on monitored data is suggested. The essence of this approach is to adopt the long-term (5-year) averages of the most recent monitored air quality data obtained by EPD. These background data would be reviewed yearly or biennially depending on the availability of the monitored data. The approach is a first attempt to provide a reasonable estimate of the background air quality level for use in conjunction with EIA air quality assessment to address the cumulative impacts upon a locality. This approach may be replaced or supplemented by superior modelling efforts such as that entailed in PATH (Pollutants in the Atmosphere and their Transport over Hong Kong), a comprehensive territory-wide air quality modelling system currently being developed for Hong Kong. Notwithstanding this, the present approach is based on measured data and their long term regional averages; the background values so derived should therefore be indicative of the present background air quality. In the absence of any other meaningful way to estimate a background air quality for the future, this present background estimate should also be applied to future projects as a first attempt at a comprehensive estimate until a better approach is formulated.

3.2 Categorisation

The monitored air quality data, by 'district-averaging' are further divided into three categories, viz, Urban, Industrial and Rural/New Development. The background pollutant concentrations to be adopted for a project site would depend on the geographical constituency to which the site belongs. The categorisation of these constituencies is given in Section 3.4. The monitoring stations suggested for the 'district-averaging' (arithmetic means) to derive averages for the three background air quality categories are listed as follows:

Urban: Kwun Tong, Sham Shui Po, Tsim Sha Tsui and Central/Western Industrial: Kwun Tong, Tsuen Wan and Kwai Chung Rural/New Development: Sha Tin, Tai Po, Junk Bay, Hong Kong South and Yuen Long

The averaging would make use of data from the above stations wherever available. The majority of the monitoring stations are located some 20m above ground.

3.3 Background pollutant values

Based on the above approach, background values for the 3 categories have been obtained for a few major air pollutants as follows:

POLLUTANT	URBAN	INDUSTRIAL	RURAL/NEW DEVELOPMENT
NO2	59	57	39
SO2	21	26	13
O3	62	68	57
TSP	98	96	87

All units are in micrograms per cubic metre. The above values are derived from 1992 to 1996 annual averages with the exception of ozone which represent annual average of daily hourly maximum values for year 1996.

In cases where suitable air quality monitoring data representative of the study site such as those obtained from a nearby monitoring station or on-site sampling are not available for the prescription of background air pollution levels, the above tabulated values can be adopted instead. Strictly speaking, the suggested values are only appropriate for long term assessment. However, as an interim measure and until a better approach is formulated, the same values can also be used for short term assessment. This implies that the short term background values will be somewhat under-estimated, which compensates for the fact that some of the monitoring data are inherently influenced by secondary sources because of the monitoring station location. Indeed, if good quality on-site sampling data which cover at least one year period are available, these can be used to derive both the long term (annual) and short term (daily / hourly) background values, the latter are usually applied on an hour to hour, day to day basis.

3.4 Site categories

The categories to which the 19 geographical constituencies belong are listed as follows:

DISTRICT	AIR QUALITY CATEGORY
Islands	Rural/New Development
Southern	Rural/New Development
Eastern	Urban
Wan Chai	Urban
Central & Western	Urban
Sai Kung	Rural/New Development
Kwun Tong	Industrial
Wong Tai Sin	Urban
Kowloon City	Urban
Yau Tsim	Urban
Mong Kok	Urban
Sham Shui Po	Urban
Kwai Tsing	Industrial
Sha Tin	Rural/New Development
Tsuen Wan	Industrial
Tuen Mun	Rural/New Development
Tai Po	Rural/New Development
Yuen Long	Rural/New Development
Northern	Rural/New Development

3.5 Provisions for “double-counting”

The current approach is, by no means, a rigorous treatment of background air quality but aims to provide an as-realistic-as-possible approximation based on limited field data. 'Double-counting' of 'secondary contributions' may be apparent through the use of such 'monitoring-based' background data as some of the monitoring stations are of close proximity to existing emission sources. 'Primary contributions' due to a proposed project (which is yet to be realised) will not be double-counted by such an approach. In order to avoid over-estimation of background pollutant concentrations, an adjustment to the values given in section 3.3 is possible and optional by multiplying the following factor:

(1.0 - E_{Secondary
contributions}/E_Territory) where E stands for emission.

The significance of this factor is to eliminate the fractional contribution to background pollutant level of emissions due to 'secondary contributions' out of those from the entire territory. In most cases, this fractional contribution to background pollutant levels by the secondary contributions is minimal.

4. Conclusions

4.1 The above described approach to estimating the total air quality impacts of a proposed project, in particular the background pollutant concentrations for air quality assessment, should be adopted with immediate effect. Use of short term monitoring data to prescribe the background concentrations is no longer acceptable.

Appendix D3 - Guidelines on the Use of Alternative Computer Models in Air Quality Assessment

1. Background

1.1 In Hong Kong, a number of Gaussian plume models are commonly employed in regulatory applications such as application for specified process licences and environmental impact assessments (EIAs). These frequently used models (as listed in Schedule 1 attached; hereafter referred to as Schedule 1 models) have no regulatory status but form the basic set of tools for local-scale air quality assessment in Hong Kong.

1.2 However, no single model is sufficient to cover all situations encountered in regulatory applications. In order to ensure that the best model available is used for each regulatory application and that a model is not arbitrarily applied, the project proponent (and/or its environmental consultants) should assess the capabilities of various models available and adopt one that is most suitable for the project concerned.

1.3 Examples of situations where the use of an alternative model is warranted include:

(i) complexity of the situation to be modelled far exceeds the capability of the Schedule 1 models; and

(ii) performance of an alternative model is comparable or better than the Schedule 1 models.

1.4 This paper outlines the demonstration / submission required in order to support the use of an alternative air quality model for regulatory applications for Hong Kong.

2. Required Demonstration / Submission

2.1 Any model that is proposed for air quality applications and not listed amongst the Schedule 1 models will be considered by EPD on a case-by-case basis. In such cases, the proponent will have to provide the followings for EPD's review:

(i) Technical details of the proposed model; and
(ii) Performance evaluation of the proposed model

Based on the above information, EPD will determine the acceptability of the proposed model for a specific or general applications. The onus of providing adequate supporting materials rests entirely with the proponent.

2.2 To provide technical details of the proposed model, the proponent should submit documents containing at least the following information:

(i) mathematical formulation and data requirements of the model;
(ii) any previous performance evaluation of the model; and
(iii) a complete set of model input and output file(s) in commonly used electronic format.

2.3 On performance evaluation, the required approach and extent of demonstration varies depending on whether a Schedule 1 model is already available and suitable in simulating the situation under consideration. In cases where no Schedule 1 model is found applicable, the proponent must demonstrate that the proposed model passes the screening test as set out in USEPA Document "Protocol for Determining the Best Performing Model"

2.4 For cases where a Schedule 1 model is applicable to the project under consideration but an alternative model is proposed for use instead, the proponent must demonstrate either that

(i) the highest and second highest concentrations predicted by the proposed model are within 2 percent of the estimates obtained from an applicable Schedule 1 model (with appropriate options chosen) for all receptors for the project under consideration; or

(ii) the proposed model has superior performance against an applicable Schedule 1 model based on the evaluation procedure set out in USEPA Document "Protocol for Determining the Best Performing Model"

2.5 Should EPD find the information on technical details alone sufficient to indicate the acceptability of the proposed model, information on further performance evaluation as specified in Sections 2.3 and 2.4 above would not be necessary.

2.6 If the proposed model is an older version of one of the Schedule 1 models or was previously included in Schedule 1, the technical documents mentioned in Section 2.2 are normally not required. However, a performance demonstration of equivalence as stated in Section 2.4 (i) would become necessary.

2.7 If EPD is already in possession of some of the documents that describe the technical details of the proposed model, submission of the same by the proponent is not necessary. The proponent may check with EPD to avoid sending in duplicate information.

Schedule 1

Air Quality Models Generally Accepted by Hong Kong Environmental Protection Department For Regulatory Applications as at 1 July 1998*

Industrial Source Complex Dispersion Model - Short Term Version 3 (ISCST3) or the latest version developed by U.S. Environmental Protection Agency (USEPA)

California Line Source Dispersion Model Version 4 (CALINE4) or the latest version developed by Department of Transportation, State of California, U.S.A.

Fugitive Dust Model (FDM) or the latest version developed by USEPA.

* EPD is continually reviewing the latest development in air quality models and will update this Schedule accordingly.