Table of Contents

 

6.           Waste management implications.. 6-1

6.1     Introduction. 6-1

6.2     Environmental Legislation, Policies, Plans and Standards. 6-1

6.3     Assessment Methodology. 6-5

6.4     Identification of Potential Sources of Impacts. 6-5

6.5     Prediction and Evaluation of Environmental Impacts. 6-5

6.6     Mitigation Measures for Adverse Environmental Impacts. 6-7

6.7     Evaluation of Residual Impacts. 6-11

6.8     Environmental Monitoring and Audit 6-11

6.9     Land Contamination Assessment 6-11

6.10   Conclusions. 6-13

6.  Waste management implications  6-1

6.1  Introduction  6-1

6.2  Environmental Legislation, Policies, Plans and Standards  6-1

6.3  Assessment Methodology  6-5

6.4  Identification of Potential Sources of Impacts  6-5

6.5  Prediction and Evaluation of Environmental Impacts  6-5

6.6  Mitigation Measures for Adverse Environmental Impacts  6-7

6.7  Evaluation of Residual Impacts  6-10

6.8  Environmental Monitoring and Audit  6-11

6.9  Land Contamination Assessment  6-11

6.10  Conclusions  6-12

 

 

List of Tables

 

Table 6‑1     Government Waste Disposal Facilities for Construction Waste

Table 6‑2     Summary of Estimated Quantities of Waste Arising from the Project

Table 6‑3     Summary of Findings of Aerial Photographs Reviewed

Table 6‑4     Potentially Contaminative Land Uses along Tsuen Wan Road

 

 

List of Figures

 

Figure 6-1        Locations and Associated Extent of Cut and Fill Areas

Figure 6-2        Locations of Potential Contaminated Land Uses


6.                       Waste management implications

6.1                    Introduction

6.1.1                This Chapter identifies the waste, which may arise during the construction works, and the potential environmental impact resulting from the handling, collection and disposal of the construction waste. It also presents an assessment of the potential for the occurrence of ground contamination along the route of the TWR upgrading works and the potential implications of alignment widening. This contamination assessment is carried out in accordance with Annex 19 of the Technical Memorandum on Environmental Impact Assessment Process (EIAO-TM), while both existing and historical land uses along the highway footprint have been taken into consideration.

6.1.2                Options for waste minimization, recycling, storage, collection, and disposal of waste arising from the Project have been examined and procedures for minimizing environmental impacts due to handling and disposal of waste are recommended. The handling and disposal of this small amount of waste are anticipated to have negligible environmental impacts and thus will not be evaluated further in this EIA Study.

6.2                    Environmental Legislation, Policies, Plans and Standards

6.2.1                The criteria and guidelines for evaluating waste management implications are provided in Annexes 7 and 15 of the EIAO-TM. The following legislation covers, or has some bearing upon, the handling, treatment and disposal of waste, and are used as assessment criteria:

·            Waste Disposal Ordinance (Cap. 354);

·            Waste Disposal (Chemical Waste) (General) Regulation (Cap. 354C);

·            Land (Miscellaneous Provisions) Ordinance (Cap. 28); and

·            Public Health and Municipal Services Ordinance (Cap. 132) - Public Cleansing and Prevention of Nuisances (Urban Council) and (Regional Council) By-laws.

Waste Disposal Ordinance

6.2.2                The Waste Disposal Ordinance (WDO) prohibits the unauthorized disposal of waste, with waste defined as any substance or article which is abandoned. Construction and demolition (C&D) waste is not directly defined in the WDO but is considered to fall within the category of "trade waste". Trade waste is defined as waste from any trade, manufacturer or business, or any waste building, or civil engineering materials, but does not include animal waste.

6.2.3                Under the WDO, waste can only be disposed of at a licensed site. A breach of these regulations can lead to the imposition of a fine and/or a prison sentence. The WDO also provides the issuing of licenses for the collection and transport of wastes. However, licenses are not currently required to be issued for the collection and transport of C&D waste and/or trade waste.

6.2.4                The Waste Disposal (Charges for Disposal of Construction Waste) Regulation defines construction waste as any substance, matters or things that is generated from construction work and abandoned, whether or not it has been processed or stockpiled before being abandoned, but does not include any sludge, screening or matter removed in or generated from any desludging, desilting or dredging works.

6.2.5                The Construction Waste Disposal Charging Scheme has come into operation on 1 December 2005. Processing of account applications by the EPD started on the same day. Starting from 1 December 2005, main Contractor who undertakes construction work under a contract with value of HK$1 million or above is required to open a billing account solely for the contract. Application shall be made within 21 days after the contract is awarded. Failing this will be an offence under the law.

6.2.6                For construction work under a contract with value less than HK$1 million, such as minor construction or renovation work, any person such as the owner of the premises where the construction work takes place or his/her Contractor can open a billing account; the account can also be used for contracts each with value less than $1 million. The premises owner concerned may also engage a Contractor with a valid billing account to make arrangement for disposal of construction waste.

6.2.7                Charging for disposal of construction waste has been started on 20 January 2006 and from this day, any person before using waste disposal facilities for disposal of construction waste needs to open an account.

6.2.8                The scheme encourages reduce, reuse and sorting of construction waste such that the waste producer can minimize their disposal fee. Table 6-1 summarizes the government construction waste disposal facilities, types of waste accepted and disposal cost.

Table 61        Government Waste Disposal Facilities for Construction Waste

Government Waste Disposal Facilities

Type of Construction Waste Accepted

Charge Per Tonne (HK$)

Public fill reception facilities

Consisting entirely of inert construction waste

27

Sorting facilities

Containing more than 50% by weight of inert construction waste

100

Landfills

Containing not more than 50% by weight of inert construction waste

125

Outlying Islands Transfer Facilities

Containing any percentage of inert construction waste

125

 

Waste Disposal (Chemical Waste) (General) Regulation

6.2.9                Chemical waste as defined under the Waste Disposal (Chemical Waste) (General) Regulation (the Regulation) includes any substance being scrap material, or unwanted substances specified under Schedule 1 of the Regulation if such substance or chemical occurs in such a form, quantity or concentration so as to cause pollution or constitute a danger to health or risk of pollution to the environment.

6.2.10            A person should not produce, or cause to be produced, chemical wastes unless they are registered with EPD. Any person who contravenes this requirement commits an offence and is liable to a fine and /or imprisonment.

6.2.11            Producers of chemical wastes must treat their wastes, utilising on-site plant licensed by EPD, or have a licensed collector take the wastes to a licensed facility. For each consignment, the waste producer, collector and disposer of the wastes must sign all relevant parts of a ‘trip ticket’, this system is designed to allow the transfer of wastes to be traced from cradle to grave.

6.2.12            The Regulation prescribes the storage facilities to be provided on site including labelling and warning signs. To minimize the risks of pollution and danger to human health or life, the waste producer is required to prepare and make available, written procedures to be observed in the case of emergencies due to spillage, leakage or accidents arising from the storage of chemical wastes. They must also provide employees with training in such procedures.

Land (Miscellaneous Provisions) Ordinance

6.2.13            Construction and demolition material, which is wholly inert, may be taken to public filling areas. Public filling areas usually form part of land reclamation schemes and are operated by the Civil Engineering and Development Department (CEDD). The Ordinance requires that public filling licences are obtained by individuals or companies who deliver inert C&D material (or public fill) to public filling areas. The licences are issued by CEDD under delegated powers from the Director of Lands.

6.2.14            Individual licenses are issued for each vehicle involved. Under the license conditions, public filling areas will accept only inert building debris, soil, rock and broken concrete. There is no size limitation on the rock and broken concrete, and a small amount of timber mixed with other suitable materials is permissible. However, the material should be free from marine mud, household refuse, plastic, metal, industrial and chemical wastes, animal and vegetable matter and any other materials considered unsuitable by the public filling supervisor.

Public Cleansing and Prevention of Nuisances By-Laws

6.2.15            These By-laws provide a further control on the illegal tipping of wastes on unauthorised (unlicensed) sites. The illegal dumping of wastes can lead to fines and/or imprisonment.

Additional Guidelines

6.2.16            Other guideline documents, which detail how the Contractor should comply with waste-related regulations are as follows:

a)      Waste Disposal Plan for Hong Kong (1989), Planning, Environment and Lands Branch Government Secretariat, Hong Kong Government;

b)      Environmental Guidelines for Planning In Hong Kong (1990), Hong Kong Planning and Standards Guidelines, Hong Kong Government;

c)      New Disposal Arrangement for Construction Waste (1992), Environmental Protection Department & Civil Engineering Department, Hong Kong Government;

d)      Code of Practice on the Packaging, Labelling and Storage of Chemical Wastes (1992), Environmental Protection Department, Hong Kong Government;

e)      Works Branch Technical Circular No. 32/92, The Use of Tropical Hard Wood on Construction Site, Works Branch, Hong Kong Government;

f)       Works Branch Technical Circular No. 2/93, Public Dumps, Works Branch, Hong Kong Government;

g)      Works Branch Technical Circular No. 2/93B, Public Filling Facilities, Works Branch, Hong Kong Government;

h)      Works Branch Technical Circular No. 16/96, Wet Soil in Public Dumps, Works Branch, Hong Kong Government;

i)        Waste Reduction Framework Plan, 1998 to 2007, Planning, Environment and Lands Bureau, Government Secretariat (1998);

j)        Works Bureau Technical Circular No. 4/98, Use of public Fill in Reclamation and Earth Filling Projects, Hong Kong Government

k)      Works Bureau Technical Circular Nos. 25/99, 25/99A and 25/99C, Incorporation of Information on Construction and Demolition Material Management in Public Works Sub-committee Papers, Works Bureau, Hong Kong SAR Government;

l)        Works Bureau Technical Circular No. 19/99, Metallic Site Hoardings and Signboards, Works Bureau, Hong Kong SAR Government;

m)    Works Branch Technical Circular No. 12/2000, Fill Management, Works Bureau, Hong Kong SAR Government;

n)      Environment, Transport and Works Bureau Technical Circular (Works) No 33/2002, Management of Construction and Demolition Material Including Rock, Environment, Transport and Works Bureau, Hong Kong SAR Government;

o)      Environment, Transport and Works Bureau Technical Circular (Works) No. 15/2003, Waste Management on Construction Sites, Environment, Transport and Works Bureau, Hong Kong SAR Government;

p)      Environment, Transport and Works Bureau Technical Circular (Works) No. 31/2004, Trip Ticket System for Disposal of Construction & Demolition Materials, Environment, Transport and Works Bureau, Hong Kong SAR Government; and

q)      Works Branch Technical Circular No. 19/2005, Environmental Management on Construction Sites, Works Bureau, Hong Kong SAR Government.

6.2.17            The assessment of contaminated land in Hong Kong is currently undertaken in accordance with the following documents:

a)      Environmental Protection Department (1994) Practice Note for Professional Persons on Contaminated Land Assessment and Remediation. ProPECC PN 3/94;Environmental Protection Department Guidance Note for Contaminated Land Assessment and Remediation (issued on 15 August 2007);

b)      Environmental Protection Department Guidance Manual for Use of Risk-based Remediation Goals for Contaminated Land Management (issued on July 2007);

c)      Environmental Protection Department (1999) Guidance Note for Investigation and Remediation of Contaminated Sites of Petrol Filling Stations, Boatyards and Car Repair/Dismantling Workshops; and

d)      Annex 19 of the EIAO-TM.

6.2.18            Annex 19 of the EIAO-TM identifies a number of land uses, which have the potential to cause land contamination. These uses include, but are not limited to, the following:

·        oil installations including oil depots and petrol filling stations;

·        gas works;

·        power stations;

·        shipyards/boatyards;

·        chemical manufacturing/processing plants;

·        steel mills/metal workshops;

·        car repairing and dismantling workshops; and

·        dumping grounds and landfills.

6.2.19            If any of the above land uses (or other potentially contaminative land uses) is identified as part of the EIA Study, a Contamination Assessment Plan (CAP) should be submitted to the Director for endorsement prior to conducting a contamination assessment of the site.

6.3                    Assessment Methodology

6.3.1                The assessment of waste management implications has been conducted in accordance with Annexes 7 and 15 of the EIAO-TM. This includes:

·        estimation of types and quantities of wastes generated;

·        assessment of potential impact caused by handling (including labelling, packaging and storage), collection, and disposal of wastes with respect to potential hazard, air and odour emission, noise, wastewater discharge and public transport; and

·        determination of practical mitigation measures for the environmental impacts.

6.4                    Identification of Potential Sources of Impacts

6.4.1                Construction activities will result in the generation of a variety of wastes which can be divided into distinct categories based on their constituents, as follows:

·            construction and demolition (C&D) material;

·            chemical waste; and

·            general refuse.

6.5                    Prediction and Evaluation of Environmental Impacts

6.5.1                The nature and preliminary quantities of each of these waste types arising from the proposed works are identified in this section. The detailed calculations of materials and waste arising are required to be submitted to Government under the requirements of WBTC 25/99 during the detailed design. Table 6-2 summarizes the estimated quantities of different types of waste arising from the Project.

Table 62        Summary of Estimated Quantities of Waste Arising from the Project

Waste Type

Source

Total Quantity

Handling

Quantity to be reused on-site

Quantity to be disposed of off-site

C&D Material

Excavation for foundation

Inert: 29,700 m3

Non-inert: 1,400 m3

Sorted on-site into inert and non-inert C&D material

14,700 m3 of inert C&D material as filling material for abutment wall and 10,000 m3 as fill embankment

85,500 m3 inert C&D material to public filling facilities*;

 

2,500 m3 non-inert C&D material to landfill*

Excavation and site clearance for at grade road construction

Inert: 7,800 m3

Non-inert: 100 m3

 

Excavation and site clearance for cut slopes

Inert: 56,500 m3

Non-inert: 300 m3

Excavation and site clearance for other formation works

Inert: 2,100 m3

Non-inert: 300 m3

Chemical Waste

Scrap batteries, spent acid/alkali, spent mineral oil/ cleaning fluid, spent solvent, engine oil and fuel from construction plants or equipment

Few hundred litres per month

Collected by licensed company; Stored on-site within suitably designed containers

--

Few hundred litres per month

General Refuse

Food waste, waste paper, aluminium cans etc generated from workforce

Approximately 280 kg per day (preliminary estimate based on workforce of 200)

Collected by on-site refuse collection point and transferred to landfill or recycling company

--

Approximately 280 kg per day (preliminary estimate based on workforce of 200)

Note: * A factor of 1.2 is applied in the estimate of C&D waste quantity to be disposed of off-site.

 

Construction and Demolition (C&D) Material

6.5.2                C&D material would be generated during the foundation works, road widening and associated slope works, reprovision of slip roads and local access roads, as well as other formation works.  Types of C&D material include soil, rock, concrete, bituminous material and timber etc, the total quantity of the C&D material generated in the Project is estimated to be approximately 98,000 m3. Among this, about 25,000 m3 of inert C&D material would be reused on-site as filling material. Approximately 85,500 m3 of inert C&D material would be disposed of to public filling facilities for other beneficial uses and about 2,500 m3 of non-inert C&D waste would be disposed of to designated landfills. Figure 6-1 shows the locations and associated extent of the cut and fill areas in the Project.

Chemical Waste

6.5.3                Chemical Waste, as defined under the Waste Disposal (Chemical Waste) (General) Regulation, includes any substance being scrap material, or unwanted substances specified under Schedule 1 of the Regulation. A complete list of such substances is provided under the Regulation, however substances likely to be generated by construction activities will, for the most part, arise from the maintenance of equipment. These may include, but not limited to, the following:

·            scrap batteries or spent acid/alkali from their maintenance;

·            used engine oils, hydraulic fluids and waste fuel;

·            spent mineral oils/cleaning fluids from mechanical machinery; and

·            spent solvents/solutions, some of which may be halogenated, from equipment cleaning activities.

6.5.4                It is difficult to quantify the amount of chemical waste which will arise from the construction activities as it will be highly dependent on the Contractor's on-site maintenance intention and the number of plants and vehicles utilised. However, it is anticipated that the quantity of chemical waste, such as lubricating oil and solvent produced from plant maintenance will be small, (in the order of a couple of hundred litres per month) and will be readily accepted at the Chemical Waste Treatment Facility (CWTF) or other licensed waste oil recycling facilities. The actual amount of chemical wastes generated should be quantified and recorded in the Site Waste Management Plan to be prepared by the Contractor.

General Refuse

6.5.5                Construction site workers, site offices and canteens will result in the generation of a variety of general refuse requiring disposal. General refuse generated on site will mainly consist of food wastes, aluminum cans and waste paper.

6.5.6                The likely maximum number of workers on-site at any one time during the construction period is 200 people. This is likely to occur at the busiest period of the works, around the end of Year 2011 to Year 2012.

6.5.7                Projections of general refuse generation are generated by EPD, in accordance with “Monitoring of Solid Waste in Hong Kong 1999”. Linear projections based on previously recorded data indicate that this rate will increase to 1.3 and 1.4kg/person/day in Year 2011 and Year 2015 respectively.

6.5.8                Therefore, it is predicted that during the period of peak activity, approximately 0.28 tonne/day of general refuse would be produced.

6.6                    Mitigation Measures for Adverse Environmental Impacts

6.6.1                The Contractor is responsible for the management of materials and wastes during construction. This includes control of wastes on site, removal of the waste materials from the site and the implementation of any mitigation measures to minimise waste or redress any problems that arise from waste associated with the works. In addition to C&D waste and domestic wastes, this material may include sewage, wastewater or any other site discharges on to adjacent land, sewers, or water courses.

6.6.2                This section sets out the measures to be adopted to avoid or minimise potential adverse impacts associated with waste arising from the works under the headings of each waste type. The Contractor should incorporate these recommendations into a comprehensive on-site Waste Management Plan, (WMP). If, for any reason, the recommendations cannot be implemented, full justification should be given in the WMP.

6.6.3                In accordance with ETWBTC(W) No 15/2003 – Waste Management on Construction Site, the WMP should be prepared and submitted for approval by the Architect/ Engineer/ Supervising Officer prior to any construction activities. During the construction period the WMP should be used as a working document to detail the on-going management procedures and to record waste arising from construction works and import of fill throughout the Contract. The WMP shall be subject to audit under the requirements of the Environmental Monitoring and Audit (EM&A) Procedures set out in the EM&A Manual accompanying this EIA Report.

Waste Management Hierarchy

6.6.4                The WMP shall be developed and implemented according to a best-practice philosophy of waste management. There are various waste management options, which can be categorized in terms of preference from an environmental viewpoint. The options considered to be more preferable have the least impacts and are more sustainable in a long-term context. The hierarchy is as follows:

·            avoidance and minimisation, i.e. avoiding or not generating waste through changing or improving practices and design;

·            reuse of materials, thus avoiding disposal (generally with only limited reprocessing);

·            recovery and recycling, thus avoiding disposal (although reprocessing may be required); and

·            treatment and disposal, according to relevant laws, guidelines and good practice.

6.6.5                The Waste Disposal Authority should be consulted by the Contractor on the final disposal of wastes.

6.6.6                The suitability (or otherwise) of material for reuse on site shall be detailed in the WMP. If, for any reason, the recommendations cannot be implemented, full justification should be given in the WMP for approval by Architect/Engineer/Supervising Officer according to ETWBTC(W) No. 15/2003.

Training

6.6.7                To facilitate adoption of the best-practice philosophy, training shall be provided to all personnel working on site. The training shall promote the concept of general site cleanliness and clearly explain the appropriate waste management procedures defined in the WMP. Overall, the training should encourage all workers to reduce, reuse and recycle wastes.

Records of Waste and Management

6.6.8                During construction, the WMP should be kept up-to-date on a monthly basis with records of the actual quantities of wastes generated, recycled and disposed of off-site. Quantities shall be determined by weighing each load or other methods agreed to by the Engineer’s Representative. Waste shall only be disposed of at licensed sites and the WMP should include procedures to ensure that illegal disposal of wastes does not occur. Only waste haulers authorized to collect the specific category of waste concerned should be employed and a trip ticket system shall be implemented for offsite disposal of C&D and solid waste at public filling facilities and landfills. Appropriate measures should be employed to minimize windblown litter and dust during transportation by either covering trucks or transporting wastes in enclosed containers.

Site Planning

6.6.9                Work site(s) shall be arranged and managed to facilitate the proper management of wastes and materials. The WMP shall include plans indicating specific areas designated for the storage of particular types of waste, reusable and recyclable materials as well as areas and management proposals for any stockpiling areas. Waste storage areas should be well maintained and cleaned regularly. Specific provisions for different types of material are outlined below. In general, these areas should be designed to avoid cross contamination of materials as well as pollution of the surrounding environment.

Construction and Demolition (C&D) Material

6.6.10            In order to minimize the impact resulting from collection and transportation of C&D material for off-site disposal, it is recommended that the excavated fill material should be reused on site as backfill material as far as possible. Also, careful design, planning and good site management should be maintained in order to minimise over ordering and generation of surplus materials such as concrete, mortars and cement grouts. The design of formwork should maximise the use of standard wooden panels so that high reuse levels can be achieved. Alternatives such as steel formwork or plastic facing should be considered to increase the potential for reuse.

6.6.11            C&D materials should be segregated on site into different waste and material types. This will increase the feasibility of certain components of the waste stream being recycled by specialised contractors. The Contractor should clearly demonstrate in the WMP how he intends to maximise the reuse of C&D material on-site. Where reuse of materials on site is not feasible, the Contractor should explore opportunities for recycling materials off-site. Inert C&D materials shall be reused on site as much as possible or recycled with the remaining non-inert materials which cannot be reused or recycled being disposed of to landfill.

6.6.12            Potential opportunities for recycling and reuse of C&D materials from the Project include:

·            milling wastes arising from regrading of the existing pavement could be recycled on site and reused as either road-base in the new carriageways or fill for new embankments;

·            existing marginal roadside barriers comprise pre-cast units, which may be possible to be reused in the following widening works; and

·            existing bridge parapets comprise aluminum post and railings, which have a recyclable value and could be sold for reconditioning or reused for scrap metal.

6.6.13            Any stockpile should be sited away from existing watercourses and suitably covered to prevent wind erosion and impacts on air and water quality. Measures for impacts on air and water quality are described in Chapters 4 and 5 in this report, respectively.

Chemical Waste

6.6.14            Chemical waste should be handled in accordance with the Code of Practice on the Packaging, Handling and Storage of Chemical Wastes as follows. Containers used for the storage of chemical wastes should:

·            be suitable for the substance they are holding, resistant to corrosion, maintained in a good condition, and securely closed;

·            have a capacity of less than 450L unless the specifications have been approved by the EPD; and

·            display a label in English and Chinese in accordance with instructions prescribed in Schedule 2 of the Waste Disposal (Chemical Waste) (General) Regulation (Cap. 354C).

6.6.15            The storage area for chemical wastes should:

·            be clearly labelled and used solely for the storage of chemical waste;

·            be enclosed on at least 3 sides;

·            have an impermeable floor and bunding, of capacity to accommodate 110% of the volume of the largest container or 20% by volume of the chemical waste stored in that area, whichever is the greatest;

·            have adequate ventilation;

·            be covered to prevent rainfall entering (water collected within the bund must be tested and disposed as chemical waste if necessary); and

·            be arranged so that incompatible materials are adequately separated.

6.6.16            The Contractor shall register with EPD as a Chemical Waste Producer. Waste oils and other chemical wastes as defined in the Waste Disposal (Chemical Waste) (General) Regulation will require disposal by appropriate means and could require pre-notification to EPD prior to disposal. Appropriate means include disposal:

·            via a licensed waste collector; and

·            to a facility licensed to receive chemical waste, such as the Chemical Waste Treatment Facility which also offers a chemical waste collection service and can supply the necessary storage containers; or

·            to a reuser of the waste, under approval from EPD. The Centre for Environmental Technology operates a Waste Exchange Scheme, which can assist in finding receivers or buyers.

General Refuse

6.6.17            General refuse generated on-site should be stored in enclosed bins or compaction units separate from construction and chemical wastes. A reputable waste collector should be employed by the Contractor to remove general refuse from the site, separately from construction and chemical wastes, on a daily or every second day basis to minimize odour, pest and litter impacts. The burning of refuse on construction sites is prohibited by law.

6.6.18            General refuse is generated largely by food service activities on site, so reusable rather than disposable dishware should be used if feasible. Aluminum cans are often recovered from the waste stream by individual collectors if they are segregated or easily accessible. Therefore separate, labelled bins for their deposit should be provided if feasible.

6.6.19            Office waste can be reduced through recycling of paper if volume is large enough to warrant collection. Participation in a local collection scheme should be considered if one is available.

6.7                    Evaluation of Residual Impacts

6.7.1                With the implementation of the recommended mitigation measures for the handling, transportation and disposal of the identified waste arising from the Project, the residual impact is expected to be minimal.

6.8                    Environmental Monitoring and Audit

6.8.1                It is the Contractor’s responsibility to ensure that all wastes produced during the construction of the Project are handled, stored, and disposed of in accordance with good waste management practices and relevant regulations and requirements. The mitigation measures recommended in Section 6.6 should form a basis of the WMP to be developed by the Contractor in the construction phase of the Project.

6.9                    Land Contamination Assessment

Methodology

6.9.1                The objective of this assessment is to identify and evaluate the potential soil contamination along TWR alignment and if required, develop an assessment plan to determine the extent of any contamination present. In order to achieve this the following has been undertaken:

·            review of the current and historical land use of the site to evaluate whether there is the potential for any soil or groundwater contamination to have occurred;

·            assess any potential environmental impacts arising as a result of land contamination or during future use of the land; and

·            site visits to confirm land uses and likely impacts of any land contamination identified.

6.9.2                In order to achieve the above, the following sources of information have been collated and reviewed:

·            road alignment maps;

·            Hong Kong Government Survey maps along the alignment;

·            aerial photographs of the alignment; and

·            selected Outline Zoning Plans (OZPs) along the alignment.

6.9.3                In addition to the above, site visits were undertaken on the 14 August 2007 along the road alignment to confirm land uses and identify potential land contamination sources.

Review of Historic Land Uses

6.9.4                The site history information of the Study Area was obtained by reviewing the relevant aerial photographs. Table 6-3 summarizes the findings of the aerial photographs reviewed.

Table 63        Summary of Findings of Aerial Photographs Reviewed

Year

Notes

1960’s

Study Area was predominantly occupied by farmlands, fishponds and included an oil depot.

1970’s

Study Area was predominantly occupied by squatters, container terminals and included an oil depot.

2007

Study Area is predominantly occupied by industrial buildings, residential areas, construction sites for residential development (i.e. TW5, TW6 and TW7), and includes Gin Drinker’s Bay Restored Landfill.

 

6.9.5                The oil depot that was formerly present within the Study Area during the 1960’s and 70’s is believed to have been decommissioned some time in the 1980’s. The Site Boundary for the TWR Upgrading Works does not encroach upon the area formerly occupied by the oil depot.

Description of Existing Environment

6.9.6                During a detailed walk over site survey on 14 August 2007, potentially contaminative land uses in the vicinity of TWR have been identified. Figure 6-2 shows the locations of the potential contaminated land uses within the Study Area.  Details are summarized in Table 6-4.

Table 64        Potentially Contaminative Land Uses along Tsuen Wan Road

No

Potentially Contaminative Land Use

Location

1

Dying Factory (慶豐染廠有限公司)

Pun Shan Street

2

Dying Factory (香港中央紡織有限公司)

Chai Wan Kok Street

3

Petrol Station

Chai Wan Kok Street

4

Car Repairing Store

Tai Pa Street

5

Pier

Beside MTR TW5 Development Area

6

Dying Factory (金泰線廠有限公司)

Ma Tau Pa Road

7

Dying Factory (半島針織廠)

Wan Lung Street

8

Oil Depot

Kwai Fu Street

9

Petrol Station

Container Port Road

10

Gin Drinkers Bay Restored Landfill

Kwai Tsing Road

 

6.9.7                The proposed TWR alignment is not anticipated to directly encroach upon any areas occupied by these potentially contaminative uses.

Implications for Road Development

6.9.8                A number of potentially contaminative land uses have been identified in the vicinity of TWR. However, the TWR Upgrading works will not encroach upon any of these identified land uses. It is not anticipated that contaminated material will be encountered during the works and thus there are minimal implications with respect to construction worker exposure to contaminated material and contaminated material disposal.

Investigation Requirements

6.9.9                Since the TWR Upgrading works are not anticipated to encroach upon any of the identified potentially contaminative land uses, a detailed contaminated land site investigation prior to the works is not required.

6.10                Conclusions

6.10.1            The Project is likely to result in the generation of a variety of wastes and require the management and disposal of C&D material, chemical waste and general refuse. Provided that the wastes are managed using approved methods described above, no unacceptable adverse environmental impacts will be envisaged.

6.10.2            The mitigation measures recommended in this Chapter should be incorporated into a WMP and applied through the contract documents to ensure that environmental nuisance does not arise.

6.10.3            There are a number of land uses adjacent to TWR that, according to Section 3.1 of Annex 19 of the EIAO-TM, have the potential to cause land contamination. The proposed TWR Upgrading works are not anticipated to encroach upon these areas, and therefore further contaminated land site investigation and assessment is not required.