7. Waste Management Implications

7.1. Introduction

This chapter identifies the types of solid wastes that are likely to be generated from the Project and evaluates the potential environmental impacts that may result from these wastes. Mitigation measures and good site practices, including waste handling, storage and disposal, are recommended with reference to the applicable waste legislations and guidelines.

7.2. Environmental Legislation, Policies, Plans, Standards and Criteria

7.2.1. The criteria and guidelines for assessing waste management implications are laid down below:

· Section 3.4.7 and Appendix F of the EIA Study Brief (ESB-243/2012)

· Annex 7 and Annex 15 of the Technical Memorandum on Environmental Impact Assessment Ordinance (EIAO (TM))

· Waste Disposal Ordinance (Cap. 354)

· Waste Disposal (Charges for Disposal of Construction Waste) Regulation (Cap. 354N)

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

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

· Public Health and Municipal Services Ordinance (Cap. 132) - Public Cleansing

Waste Disposal Ordinance (Cap. 354)

7.2.2. The Waste Disposal Ordinance (WDO) prohibits the unauthorised disposal of wastes, with waste defined as any substance or article that is abandoned. Under the WDO, wastes 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 for the issuing of licences for the collection and transportation of wastes. Licences are not, however, currently issued for the collection and transport of construction waste or trade waste.

7.2.3. The Waste Disposal (Charges for Disposal of Construction Waste) Regulation defined construction waste as any substance, matters or things that are 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.

7.2.4. The Construction Waste Disposal Charging Scheme came into operation on 1 December 2005. Processing of account applications by the EPD started on the same day. A contractor who undertakes construction work with value of HK$1 million or above is required to open a billing account solely for the contract. Charges for the disposal of construction waste started on 20 January 2006.

7.2.5. Depending on the percentage of inert elements in the material, construction waste can be disposed of at public fill reception facilities, landfills and outlying islands transfer facilities, where differing disposal costs would be applied. The scheme encourages waste reduction so that the Contractor or Project Proponent can minimise the costs. Table 7.1 summarises the Government’s construction waste disposal facilities, the types of waste accepted, disposed, and the associated costs.

Table 7.1 Government Waste Disposal Facilities for Construction Waste

Government Waste Disposal Facilities	Type of Construction Waste Accepted	Charge Per Tonne
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

Source: Construction Waste Disposal Charging Scheme

Environment, Transport and Works Bureau (ETWB) Management of Construction and Demolition Material Including Rock (ETWB TCW No. 33/2002)

7.2.6. Measures have been introduced under Environment, Transport and Works Bureau (ETWB) Management of Construction and Demolition Materials Including Rock (ETWB TCW No. 33/2002), to enhance the management of construction and demolition material, and to minimize its generation at source. The enhancement measures include:

· Drawing up a Construction and Demolition Material Management Plan (C&DMMP) during the feasibility study or preliminary design stage to minimize C&D material generation and encourage proper management of such materials;

· Vetting of the C&DMMP prior to upgrading of the Project to Category A in the Public Works Programme; and

· Providing the Contractor with information from the C&DMMP in order to facilitate the preparation of the Waste Management Plan (WMP) as well as to minimize C&D material generation during construction. Projects generating C&D material less than 50,000m³ or importing material less than 50,000m³ are exempted from the C&DMMP.

7.2.7. The Environmental Management on Construction Sites (ETWB TCW No. 19/2005) includes procedures on waste management. It requires Contractors to reduce the disposal of C&D materials during the course of construction. Under ETWB TCW No. 19/2005, the Contractor is required to prepare and implement an Environmental Management Plan (EMP) and the Waste Management Plan (WMP) becomes part of the EMP.

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

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

· Code of Practice on Package, Labelling and Storage of Chemical Wastes (1992), Environmental Protection Department, Hong Kong

· Works Branch Technical Circular (WBTC) No. 2/93, Public Dumps

· WBTC No. 2/93B, Public Filling Facilities

· WBTC No.16/96, Wet Soil in Public Dumps

· WBTC Nos. 4/98 and 4/98A, Use of Public Fill in Reclamation and Earth Filling Projects

· WBTC Nos. 25/99, 25/99A and 25/99C, Incorporation of Information on Construction and Demolition Material Management in Public Works Subcommittee Papers

· WBTC No. 12/2000, Fill Management

· WBTC No. 11/2002, Control of Site Crusher

· WBTC No. 12/2002, Specification Facilitating the Use of Recycled Aggregates

· DEVB TC(W) No.6/2010, Trip Ticket System for Disposal of Construction & Demolition Materials

· ETWB TC (W) No. 19/2005, Environmental Management on Construction Sites

7.3. Description of the Existing Environment

7.3.1. The Subject Site is located at the existing ash lagoons in Tsang Tsui, Tuen Mun, overlooking the Deep Bay in the north-western New Territories. The Subject Site within area of approximately 30,000m²(3 hectares) located at the west portion of the Middle Ash Lagoon, was leased to China Light & Power Company Ltd. (CLP) for the storage of pulverized fuel ash (PFA). A location plan of this potential site is shown in Figure 1.1.

7.3.2. Other than the Subject Site, the remaining Middle Ash Lagoon area will be taken over by the Environmental Protection Department (EPD) as an extension of WENT Landfill (WLES). According to the approved EIA report from EPD for the Development of the Integrated Waste Management Facilities (IWMF) Phase 1 (application no. EIA 201/2011), the area directly to the east of the Subject Site is one of the potential sites for the IWMF Phase 1. Further to the east in the East Lagoon, a Sludge Treatment Facilities (STF) development is currently under construction.

7.3.3. Since the nature of waste generation is dependent on the amount of occupancy within site, the environmental condition pertaining to waste is expected to be unaffected in the absence of the project.

7.4. Description of Assessment Methodology

7.4.1. The assessment was undertaken in accordance with the criteria presented in Annexes 7 and 15 of the EIAO (TM) and Section 3.4.7 of the EIA Study Brief (ESB-243/2012) for the Project, as follows:

· Estimation of the types, quality, quantities and timing of the wastes to be generated based on sequence and duration of the decommissioning and construction activities;

· Evaluation of different methods for reducing waste generation and reuse/recycling on-site or off-site;

· Estimation of categories and quantities of waste required to be disposed of and description of the disposal options; and

· Evaluation of the potential impact caused by handling (including labelling, packaging and storage), collection, and reuse/disposal of wastes is addressed in detail and appropriate mitigation measures have been proposed. The assessment covers the potential hazard, air and odour emissions, noise, wastewater discharge and public transport.

7.5. Identification, Prediction and Evaluation of Environmental Impacts

7.5.1. The construction activities to be carried out for the proposed Project would generate a variety of wastes that can be divided into distinct categories based on the composition and ultimate method of disposal. The identified waste types include:

· Construction and Demolition (C&D) materials;

· General refuse; and

· Chemical waste.

7.5.2. Each type of waste arising is described in Section 7.5.3 – 7.5.14, together with an evaluation of the potential environmental impacts associated with the generation, handling, storage and transportation of the waste.

Construction and Demolition (C&D) materials

7.5.3. Construction and demolition (C&D) materials would be generated from decommissioning of site, site formation works and construction of drainage and road works. The site formation work will only involve backfilling works and the upgrading of existing access road will involve minor repairing and road-widening works, it is estimated that there will be minimal C&D wastes generated from the Subject Site. Timbers will be used for temporary works and shall be reused in other sites or recycled.

7.5.4. The C&D materials should be re-used on-site for filling works efficiently to minimize the net amount of C&D materials generated from the Project. Filling works would include site formation, backfilling and access road construction. To avoid offsite disposal, all PFA would be required to be totally reused within the site boundary and demanded in contractual specifications.

7.5.5. The estimated amount of C&D fill material is 30,000 m³ for Subject Site and 10,000 m³ for Construction Access Road Area. C&D fill material shall comply with general filling material composition, as specified in Architectural Services Department General Specification for Building 2012 Edition, Section 3 Excavation and Earthwork. Contractor shall be required to import fill complying with the specification. The truck management and transport of C&D materials for filling will depend on scheduling works by the Contractor, so while stockpiling of C&D materials are expected to be minimal, the Contractor will be required to designate an area for C&D fill stockpiling. Other C&D materials such as paper/cardboard packaging and temporary wood used during construction and decommissioning is expected to be minimal. More accurate estimates of C&D materials would be quantified in the site Waste Management Plan to be prepared by the Contractor. Open stockpiles of construction materials (e.g. aggregates sand and fill material) and excavated piles on sites shall be covered with tarpaulin or similar fabric during rainstorms. Measures should be taken to prevent the washing away of construction materials, soil, silt or debris into any drainage system.

7.5.6. Since the construction activities would be located near the coast and a stream, improper management of C&D materials may introduce debris and pollutants to the water bodies. The subsequent improper C&D material management will have irreversible impact on the water bodies. However, proper site practices are expected to be implemented, and the C&D material kept within bounds of the Subject Site, thus the impact arising from C&D materials would be minimal.

7.5.7. The general fill material required for decommissioning will be sourced from Fill Bank as far as practicable.

General refuse

7.5.8. The construction workforce would generate general refuse such as food scraps, waste paper, and empty containers. Disposal of general refuse into coastal waters will not be permitted, as introduction of these wastes is likely to have detrimental effects on water quality in the area. Rapid and effective collection of site wastes would be required to prevent waste materials being blown around by wind or flushed into the coastal waters or stream.

7.5.9. The work sites may also attract pests and vermin, in addition to creating odour nuisance if the waste storage area is not well maintained and cleaned regularly. Disposal of refuse at sites other than approved waste transfer or disposal facilities shall be prohibited. Effective collection of site wastes would be required to prevent waste materials being blown around by wind, flushed or leached into the marine environment, or creating an odour nuisance. The waste storage area should be well maintained and cleaned regularly so as to prevent attracting pests and vermin and creating any odour nuisance to the work sites.

7.5.10. The maximum number of construction workers to be employed is estimated to be approximately 50 workers. Based on a generation rate of 0.65 kg per worker per day (referenced from the IWMF EIA report EIA-201/2011), the maximum daily arising of general refuse during the construction period would be approximately 32.5 kg.

7.5.11. With the implementation of waste management practices at the site (as recommended in Section 7.6 below), adverse environmental impacts on potential hazard, air and odour emissions, noise, wastewater discharge, and public transport would not be expected from the storage, handling and transportation of refuse.

Chemical waste

7.5.12. The maintenance and servicing of construction equipment may generate chemical wastes, for instance, cleaning fluids, solvents, lubrication oil and fuel. While it may be difficult to quantify the amount of chemical waste since it will be dependent on the Contractor’s on-site maintenance needs and the amount of plant utilized, it is anticipated that the quantity of chemical waste, such as lubricating oil and solvent produced from plant maintenance, would be minimal to the order of a few cubic metres per month. The amount of chemical waste expected to be generated will be quantified in the site Waste Management Plan to be prepared by the Contractor.

7.5.13. Chemical wastes generated during the construction phase may pose environmental, health and safety hazards if not stored and disposed of in an appropriate manner as stipulated in the Waste Disposal (Chemical Waste) (General) Regulations. The potential hazards include:

· Toxic effects to workers;

· Adverse impacts on water quality from spills; and

· Fire hazards.

7.5.14. Materials classified as chemical wastes will be require special handling and storage arrangements before removal for appropriate treatment such as the Chemical Waste Treatment Facility at Tsing Yi. Wherever possible opportunities should be taken to reuse and recycle materials. Mitigation and control requirements for chemical wastes are detailed in Section 7.6 below. Provided that the handling, storage and disposal of chemical wastes are in accordance with these requirements, adverse environmental impacts are not expected to result.

7.6. Mitigation of Adverse Environmental Impacts

7.6.1. This section recommends the mitigation measures to avoid or reduce potential adverse environmental impacts associated with handling, collection and disposal of waste arising from the Project.

7.6.2. The Contractor will submit a Waste Management Plan (WMP) prior to the commencement of construction work, in accordance with the ETWB TC(W) No.19/2005 so as to provide an overall framework of waste management and reduction. The Contractor will incorporate these recommendations into a Waste Management Plan for the construction works. The Contractor will submit the plan to Engineer Representative for endorsement prior to the commencement of the construction works. Such plan will incorporate site-specific factors, such as the designation of areas for the segregation and temporary storage or reusable and recyclable materials.

7.6.3. As mentioned in Section 7.5 above, all PFA shall not leave site, and therefore a designated area for any necessary PFA stockpiling shall be provided before being reused as fill. In addition to PFA stockpiling on-site, another designated area should be provided for C&D materials, properly separated with signage to indicate type of material. All stockpiling must be covered with tarpaulin or similar fabric every day after working hours and during rainstorms, to prevent washing away of material and silts.

7.6.4. It is the Contractor’s responsibility to confirm that only reputable licensed waste collectors are used and that appropriate measures to reduce adverse impacts, including windblown litter and dust from the transportation of these wastes, are employed. In addition, the Contractor must confirm that all the necessary permits or licences required under the Waste Disposal Ordinance are obtained for the construction and operation phases.

Waste Management Hierarchy

7.6.5. The various waste management options are categorised in terms of preference from an environmental viewpoint. The options considered to be most preferable have the least environmental impacts and are more sustainable in the long term. The hierarchy is adopted following the order of preference:

· Avoidance and reduction;

· Reuse of materials;

· Recovery and recycling; and

· Treatment and disposal.

7.6.6. The above hierarchy has been used to evaluate and select waste management options. The aim is to reduce waste generation, reduce waste handling and disposal costs. Project Team will confirm that the Contractor consult EPD for the final disposal of wastes and as appropriate, implement the standard site practices and mitigation measures recommended in this Report and those given below:

· Obtain the necessary waste disposal permits from the appropriate authorities, in accordance with the Waste Disposal Ordinance (Cap. 354) and Waste Disposal (Chemical Waste) (General) Regulation;

· Nomination of approved personnel to be responsible for standard site practices, arrangements for collection and effective disposal to an appropriate facility of all wastes generated at the site;

· Use of a waste haulier licensed to collect specific category of waste;

· Training of site personnel in proper waste management and chemical handling procedures;

· Provision of sufficient waste disposal points and regular collection for disposal;

· Appropriate measures to reduce windblown litter and dust prevention of waste by either covering trucks or by transporting wastes in enclosed containers;

· Separation of chemical wastes for special handling and appropriate treatment at the Chemical Waste Treatment Centre at Tsing Yi;

· Routine cleaning and maintenance programme for drainage systems, sumps and oil interceptors;

· Regular cleaning and maintenance programme for drainage systems, sumps and oil interceptors; and

· A recording system for the amount of wastes generated/ recycled and disposal sites.

Waste Reduction Measures

7.6.7. Good management and control can prevent generation of significant amount of waste. Waste reduction is best achieved during the planning and design stage, as well as by ensuring the implementation of standard site practices. Recommendations to achieve waste reduction include:

· Segregation and storage of different types of waste in different containers, skips or stockpiles to enhance reuse or recycling of material and the proper disposal;

· Encourage collection of aluminium cans and waste paper by individual collectors during construction with separate labelled bins to segregate these wastes from other general refuse by the workforce;

· Any unused chemicals and those with remaining functional capacity will be recycled as much as possible;

· Use of reusable non-timber formwork to reduce the amount of C&D materials;

· Prior to disposal of construction waste, wood, steel and other metals will be separated to a practical extent, for re-use and/or recycling to reduce the quantity of waste to be disposed of to landfill;

· Proper storage and site practices to reduce the potential for damage or contamination of construction materials; and

· Plan and stock construction materials carefully to reduce amount of waste generated and avoid unnecessary generation of waste.

Management of Waste Disposal

7.6.8. The Contractor will open a billing account with EPD in accordance with the Waste Disposal (Charges for Disposal of Construction Waste) Regulation for the payment of disposal charges. Every waste load transferred to Government waste disposal facilities such as public fill, sorting facilities, landfills or transfer station will require a valid “Chit” which contains the information of the account holder to facilitate waste transaction recording and billing to the waste producer. A trip-ticket system will be established in accordance with DEVB TC (W) No.6/2010 to monitor the reuse of surplus excavated materials off-site and disposal of construction waste and general refuse at transfer stations/ landfills, and to control fly-tipping. The billing “chit” and trip ticket system will be included as one of the contractual requirements and implemented by the Contractor. Inspection of the waste management measures implemented on site as described in the Waste Management Plan is to be prepared before commencement of construction.

7.6.9. A recording system for the amount of waste generated, recycled and disposed of (including the disposal sites) will be established during the construction stage.

Measures for the Reduction of C&D Materials Generation

7.6.10. Majority of the inert C&D materials (rock and soil) will be reused within the Project. Public fill and construction waste shall be segregated and stored in different containers or skips to facilitate reuse or recycling of materials and the proper disposal. Specific areas of the work site will be designated for such segregation and storage if immediate use is not practicable.

7.6.11. To reduce the potential dust and water quality impacts of site formation works, C&D materials will be wetted as quickly as possible after filling.

Chemical Waste

7.6.12. Chemical waste producers will be registered with the EPD. Chemical waste, as defined by Schedule 1 of the Waste Disposal (Chemical Waste) (General) Regulation, will be handled in accordance with the Code of Practice on the Packaging, Handling and Storage of Chemical Wastes as follows. Containers used for storage of chemical wastes will:

· 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 450 L 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 Regulations.

7.6.13. The storage area for chemical wastes will:

· 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 of as chemical waste, if necessary); and

· Be arranged so that incompatible materials are appropriately separated.

7.6.14. Chemical waste will be disposed of:

· 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 container

General Refuse

7.6.15. General refuse will be stored in enclosed bins or compaction units separately from construction and chemical wastes. Adequate number of waste containers will be provided to avoid over-spillage of waste. A reputable waste collector will be employed by the Contractor to remove general refuse from the site, separately from construction and chemical wastes on a daily basis to minimise odour, pest and litter impacts. The burning of refuse on constructi on sites is prohibited by law.

7.6.16. Recycling bins will be provided at strategic locations to facilitate recovery of aluminium can and waste paper from the site. Materials recovered will be sold for recycling.

7.7. Definition and Evaluation of Residual Environmental Impacts

With the implementation of the recommended mitigation measures for the handling, transportation and disposal of the identified waste impacts, the residual environmental impacts are defined as any remaining waste-related impacts. Low to negligible residual impact is expected to arise during the decommissioning and construction phases of the west portion of the Middle Ash Lagoon.

7.8. Identification and Evaluation of Operational Phase Environmental Impact

As defined in Section 2.5, operational phase is defined as the period when the decommissioning works as detailed in Section 2 are completed. The operational phase of the Project shall be an idle buildable land to cater any future developments by the government. Since the operational phase does not involve any equipment operation or human activities, adverse environmental impacts is not expected.

7.9. Environmental Monitoring & Audit

7.9.1. It is recommended that monthly site audits of the waste management practices be carried out during the Project span to determine if wastes are being managed in accordance with the good site practices as described in this EIA Report. The audits should examine all aspects of waste management including waste storage, recycling, transport and disposal.

7.9.2. Further details of the specific EM&A requirements are detailed in Section 12 of this Report and in the EM&A Manual.

7.10. Conclusions and Recommendations

The waste management assessment has reviewed the potential impacts from various types of wastes generated from the Project. No excavated materials considered “waste” have been identified from site preparation. Analysis of the Project activities, the quantity, quality and timing of waste, chemical waste arising from maintenance of equipment, general waste from daily activities have been conducted. Provided that waste is handled, transported and disposed of using approved methods and that the recommended good site practices are strictly followed, adverse environmental impacts would not be expected during the decommissioning and construction phase.

7.2. Environmental Legislation, Policies, Plans, Standards and Criteria

Waste Disposal (Chemical Waste) (General) Regulation (Cap. 354)

Other References

7.6. Mitigation of Adverse Environmental Impacts

General Refuse

7.7. Definition and Evaluation of Residual Environmental Impacts

7.10. Conclusions and Recommendations