1

9. WASTE IMPACT ASSESSMENT

9.1 Introduction

9.1.1 This waste assessment examines the quantity, quality and timing of potential sources of waste which will arise from the construction and operation of the Spur Line. Both construction waste, and solid waste will be considered. Solid waste includes domestic waste, commercial and industrial waste, chemical waste, special wastes and other wastes, while construction and demolition waste includes most wastes arising during construction. Where unacceptable waste impacts are identified, appropriate mitigation measures are recommended. Disposal options will be outlined for each type of waste, and the responsibilities for disposal or recycling discussed.

9.1.2 The methodology follows the criteria laid out in the TM on EIA Process in Annexes 7 and 15. The most important legislation regulating waste arisings is the Waste Disposal Ordinance [Cap 354].

9.1.3 The main objectives of the waste assessment are to:

(i) identify the sources, volumes, quality and timing of wastes arising from the construction activities;

(ii) recommend both construction and operational waste management strategies and control measures/routings (including final disposal sites) in accordance with the current legislative and administrative requirements for the disposal of construction waste, including waste reduction, reuse and recycling for inclusion into contract documents; and

(iii) recommend measures for the disposal of inert materials and wastes.

9.2 Construction Waste

Introduction

9.2.1 Construction waste includes waste arising from tunnel excavation, land excavation, site formation, civil/building construction, roadwork, renovation or demolition activities. Waste includes various types of excavated materials, building debris, rubble, earth, concrete, timber and mixed site clearance materials. The Contractor is responsible for transfer of the waste material to public filling areas, reclamations, marine spoil grounds or landfills, depending on the type of material and the percentage of inert material.

9.2.2 Careful calculation of waste quantities and the speed of their generation has allowed the formulation of plans for their efficient removal and disposal, with the aim of minimal disruption to traffic flow and maximum environmental protection. In addition elimination of over-ordering of construction materials will reduce waste.

9.2.3 The HKSAR Government’s construction and demolition waste management policy follows the same hierarchy as for other wastes i.e. in order of desirability: avoidance, minimisation, recycling, treatment and safe disposal of construction materials. During the construction period the contractor, engineer and environmental assessors should work closely together with a view to reducing the volumes of materials requiring removal and final disposal.

9.2.4 The main Spur Line works will involve tunnelling for a 4.3 km section of the rail line, the formation of Kwu Tung Station box, piling works to support the viaduct section of the alignment, construction of ventilation buildings, Emergency Access Points (EAPs) and cut and cover works at tunnel portals. The main construction and demolition material generated from these construction activities will be:

· excavated material

· site clearance waste/demolition waste

· concrete waste; and

· general works waste

9.2.5 Training of construction staff should be undertaken by the Contractor in order to increase awareness of waste management issues. Requirements for staff training should be included in the contractor's site waste management plan. Contractors should be made aware, though the use of contract clauses, that waste may only be disposed of at specified locations, and that illegal dumping, including into wetlands will not be tolerated.

Tunnelling Waste and Excavated Materials

9.2.6 The majority of materials excavated will arise during excavation at both tunnel portals and the TBM launching shaft, the excavation for Kwu Tung Station Box, and from the boring of the two tunnels. Much of the material to be excavated from the tunnel will be softer alluvial material with a smaller quantity of rock. Superficial deposits will be encountered at the eastern end of the alignment. From the geological profile (Figure 9.1) it can be seen that these deposits include a discontinuous layer of fill ranging from soft silt and clay to medium density sands and gravels. In some sections of the alignment bedrock will be encountered. The bedrock is mainly volcanic and at most sections where rock is encountered there will be a mix of rock and soft phase material.

9.2.7 Table 9.1 provides details of the locations of material generation and expected amounts of fill which will need to be imported for the construction of the Spurline.

Table 9.1

Locations of Construction Activities and

Amounts of Material to be Generated or Imported

Contract	Construction Activities	Chainage Start	Chainage End	Generated Quantity (m³)	Quantity of Material Required (m³)
LCC 300	Lok Ma Chau Station foundations	-	-	24,000	0
	Lok Ma Chau terminus platform	-	-	0	450,000
	Lok Ma Chau surrounding areas	-	-	0	227,000
	Lok Ma Chau EVA	-	-	20,000	23,000
LCC 202	Viaduct Section – foundations	35+420	37+390	27,500	0
	Viaduct Maintenance access	35+420	37+390	7,000	20,000
	Viaduct EAP	35+420	37+390	2,000	5,000
LDB 201	Western Open Ramp	34+885	35+200	40,000	4,000
	Western Cut and Cover Tunnel	34+680	34+885	103,000	31,000
	TBM Recovery Shaft	34+515		41,000	6,000
	Western Ventilation Building	34+850		500	0
	Bored-Tunnel	33+118 31+105	34+530 32+792	390,000	0
	Western EAP Shaft	33+900		6,000	0
	Kwu Tung Station Box	32+792	33+118	256,000	18,000
	Eastern EAP Shaft	32+100		6,000	0
	Eastern Ventilation Building	31+080		9,000	0
	TBM Launching shaft	30+985	31+125	83,000	26,000
	Eastern Cut and Cover Tunnel	30+430	31+060	181,000	15,000
	Eastern Open Ramp	30+200	30+430	22,000	0
	TOTAL			1,218,000	825,000

NOTE: Most excavated material will be reusable in the works or in public filling areas. Some material from the Lok Ma Chau station are will be re-usable in the ecological mitigation area. The column detailing Quantity of Material Required accounts for both the imported fill material plus reused material.

9.2.8 In addition to rock material there will be significant quantities of unsuitable excavated material from the foundation works for Lok Ma Chau station. It is expected that most of this material will be muddy deposits from fishponds.

9.2.9 Excavated material from the fishponds may be stockpiled, provided measures are taken to reduce odour and run-off. There is a potential that this material may be contaminated with high levels of organics, and therefore be unsuitable for re-use on site. In this case, the fishpond spoil should be drained and disposed of in accordance with WBTC 22/92. In the case that the pond material is found to be uncontaminated, it may be drained and re-used for suitable purposes on site such as in the ecological mitigation area. Measures to control dust pollution and runoff from stockpiles are given in the relevant chapters for air and water pollution. Should marine disposal of any material be considered, the material will be subject to the recommendations of WBTC No.3/2000, as construction will be commencing in 2002.

9.2.10 At most locations excavated material will be exported, and disposed of off site due to programming constraints. In some places however, the material generated can be used in place of imported fill, hence reducing both the amount of material to be disposed of off site, and the amount to be imported for works. At Lok Ma Chau station most of the material generated is expected to be unsuitable and therefore will require off-site disposal. At this location most of the materials needed for construction should be imported.

9.2.11 Some contaminated material may require excavation in Kwu Tung or Pak Shek Au in order to clear land for the formation of the Kwu Tung Station box and TBM launching and recovery shafts, Emergency Access Points (EAPs) or cross passages. This material may comprise concrete from workshops or chemical storage areas, or contaminated solids. The level and type of contamination must first be determined, in accordance with the Contamination Assessment Plan (CAP) described in the Contaminated Land Assessment Chapter of this report. Following sampling and assessment of the analysis results, remediation options will be considered. Where large volumes of contaminated soil are found, remediation should be considered as a first option. Smaller volumes of contaminated material, less contaminated soils, or concrete mixed waste may be disposed of to landfill. This option should only be considered after other options of in-situ treatment have been discounted. Details of remediation options are given in the Contaminated Land Assessment Chapter and proposals will be made in the Remediation Action Plan to be prepared before construction commences.

9.2.12 Effective from 1 July 1999, the Contractor must comply with the trip-ticket system for the disposal of Construction and Demolition (C&D) material (Works Bureau Technical Circular (WBTC) No. 5/99 Ref: WB(W)211/32/02). At the current time CED has agreed to receive uncontaminated material, such as the tunnel spoil, to public filling areas. Preliminary discussions have indicated the most likely location is Tseung Kwan O Area 137 and/or Tuen Mun Area 38.

9.2.13 Confirmation has to be sought from the Public Fill Committee (PFC) and EPD regarding the availability of public filling facilities or a landfill, for inert C&D waste and non-inert C&D waste respectively.

9.2.14 Particular Specification of the Project shall include the following clauses with the terminology defined under WBTC No. 4/98:

· The Contractor shall produce a Construction and Demolition Material Disposal Delivery Form (the Form) for each and every vehicular trip transporting construction and demolition (C&D) material, i.e. public fill or C&D waste, off Site. The Contractor shall complete the Form in duplicate except for the Time of Departure.

· Prior to the vehicle leaving the Site, the Contractor shall present to the site supervisory staff the completed Form. The site supervisory staff shall retain a copy of the Form and return the original to the Contractor. The Form shall be carried on board the vehicle at all times throughout the vehicular trip.

· For each vehicular trip, the Contractor shall obtain a receipt from the operator of the public filling facility or the landfill. The Contractor shall submit the original receipt to the Engineer’s Representative within 5 working days of the vehicular trip. Late return without any acceptable reason might be regarded as non-compliance by the Engineer’s Representative.

· The Contractor acknowledges and shall permit the Engineer Representative to request and obtain information from the operator of the Designated Disposal Tip verifying the receipt and the accuracy of the information on that receipt.

· All C&D material shall become the property of the Contractor when it is removed from the Site. The Contract should make provision that the Contractor will deliver material to the designated locations as agreed with CED.

9.2.15 The Contractor will be required to complete the relevant details on a standard form and submit the form for stamping and collection by site supervisory staff and submit to Engineer Representative the receipt issued by the operator of the public filling facility / landfill after the disposal of the C&D material. Details to be included on the standard form and the receipt is included in the WBTC No. 5/99.

9.2.16 An estimate of the material volumes involved during excavation and volumes required for fill indicates that there will be a shortfall of material for the station foundation and formation of roads (temporary and permanent) along the alignment. One of the main difficulties with re-using materials at the station is due to programme constraints. The terminus platform will be built early in the Project, whilst excavation works where suitable fill may be generated will be carried out later on. This is also due to the need for sand fill in site formation works at Lok Ma Chau station. Excavated material from the tunnel is not likely to be suitable for use as fill and surcharge material because it is predominantly soft material. However, some sections of the tunnel boring operation are through rock and where possible this should be retained for use in the station formation. Transport constraints may also cause unacceptable delays to the filling programme for the station. Traffic issues are not dealt with in this EIA and are detailed in PFC Paper 5/2001 submitted by KCRC to the PFC in October 2001.

9.2.17 In order to make maximum use of suitable fill materials available, it is proposed to use suitable material from other projects, which would otherwise go to public filling areas, in the station site formation. This ensures beneficial use of otherwise waste materials. Potential impacts from dust during the filling process are fully addressed in the Air Chapter of the EIA report.

9.2.18 To avoid generation of unsuitable material as far as possible, removal of pond bund material will be minimised through appropriate ground preparation techniques such as the use of wick drains. Where pond material is generated it should be re-used in the wetland compensation area to the south of the station works area, where the ground needs to be raised for marsh formation before major works on the station begins. All material which is re-useable should be retained for use within the site and the programme should be designed so that deficit and surplus can be balanced as far as possible. Pond material to be reused should be tested to make sure it is not contaminated before re-use.

9.2.19 Excess imported river sand after the surcharge period for the station platform could be beneficially re-used in other areas of the wetland compensation area, such as the formation of the reedbed east of the station platform.

9.2.20 Table 9.2 summarises waste generation and types and quantities estimated to be re-used. This table also summarises the amounts of inert and no inert wastes to be generated by excavation activities.

Table 9.2

Summary of C&D Materials for the Spur Line Project

Contract	Inert C&D Materials (m³)						Non-inert C&D Materials (m³)
	Generated		Reused		Surplus		Potentially Contaminated	Marine Sediment
	Soils	Rock	Soils	Rock	Soils	Rock	Potentially Contaminated	Marine Sediment
LDB 201	1,080,000	50,000⁽¹⁾	50,000⁽²⁾	0	1,030,000	50,000⁽¹⁾	7,500	0
LCC 202	20,000	0	0	0	20,000	0	500	16,000
LCC 300	35,000	0	0	0	35,000	0	0	9,000
Total	1,185,000		50,000		1,135,000		8,000	25,000

NOTE:

Rock derived from TBM excavation with typical particle size of the order of 50mm.

50,000 m³ reused along the tunnel alignment

Total material generated = 1,185,000 + 8,000 + 25,000 = 1,218,000

Proposed Works areas and Rate of Waste Generation

9.2.21 Figure 9.2 shows works areas where the majority of waste is generated, the quantity of waste and the rate of generation. The amounts are quantified in Tables 9.3 and 9.4 which refer to specific contracts within the Spur Line construction. The works included in each contract are summarised below:

· Contract LDB 201 covers the tunnel from Sheung Shui Chau Tau and includes Kwu Tung station box (Chainage 30+200 to 35+200).

· Contract LCC 202 covers the viaduct section from Chau Tau to the terminus at Lok Ma Chau (Chainage 35+200 to 37+390).

· Contract LCC 300 includes the station foundation and building works at Lok Ma Chau station.

Table 9.3

Yearly Quantities of Surplus Inert C&D Materials

Contract	Surplus Inert C& D Materials (m³)
Contract	2002	2003	2004	2005	2006
LDB 201	52,000	507,000	354,000	165,000	2,000
LCC 202	0	13,000	7,000	0	0
LCC 300	0	15,000	15,000	5,000	0

NOTE: Quantities are estimated from surplus after re-use and therefore differ slightly to figures given in Table 9.1

Table 9.4

Yearly Quantities of Fill Requirements

Contract	Fill Requirements (m³)
Contract	2002	2003	2004	2005	2006
LDB 201	0	0	0	50,000	0
LCC 202	0	25,000	0	0	0
LCC 300	0	700,000	0	0	0

NOTE: Quantities are estimated for purposes of overall waste requirements and therefore differ slightly from Table 9.1

Of the 700,000 m³ required for LCC300 300,000 will be obtained from a designated source as advised by the Secretary of the Public Fill Committee.

The 25,000 m³ of public fill required for LCC202 will be similarly obtained.

9.2.22 Some of the volumes given in Tables 9.3 and 9.4 are different from those in Table 9.1 as noted. This is due to Table 9.3 taking account of the potential for re-use of material generated, whereas Table 9.1 quotes a total volume generated.

9.2.23 The route for material generated from the works will be directly to Fanling Highway and at the time of writing the most probable destination as agreed with CED is Tseung Kwan O Area 137 and/or Tuen Mun Area 38 public filling areas. As listed in Tables 9.3 and 9.4 and shown in Figure 9.2 the rate of production of material from the LDB 201 contract (which includes the tunnel and associated works including Kwu Tung Station and the launching and recovery shafts) is slow, at around 500m³ material per day, or and average of 100 lorry loads. The maximum likely daily number of lorries for either other contract is 8. At the time of maximum material generation from tunnelling or excavation works it is predicted that a maximum of 150 – 250 lorry loads per day of material could be generated by all three contracts collectively (KCRC 2001). As the traffic will be directed along a major highway the overall impact on traffic is however, expected to be small.

9.2.24 Table 9.5 gives a summary of waste arisings, quantities, characterisation and materials balance.

Site Clearance Waste/Demolition Waste

9.2.25 The Spur Line alignment passes though, and for the majority of the alignment, beneath an area comprising agricultural land, fish ponds, open storage and temporary structures. Site clearance works will involve the removal of vegetation (mainly grasses and shrubs), demolition and building materials (from temporary structures and village houses) and a small portion of the available topsoil. Most of this site clearance will be around the tunnel portals and the area to be excavated for the box at Kwu Tung Station.

9.2.26 Demolition of the temporary structures and houses will generate concrete rubble, plastics, metal, glass, asphalt from surfaces, wood and refuse.

9.2.27 All construction wastes should be sorted on site into inert and non inert components. Non inert materials (wood, glass and plastic) should be recycled and reused wherever possible and disposed of to landfill only as a last resort, whilst inert materials (soil, rubble, sand, rock, brick and concrete) should be separated and disposed of at public filling areas operated by CED. Steel and other metals should be recovered from demolition waste and recycled as far as practicably possible.

9.2.28 The identification of final disposal sites for spoil created by the construction works should be considered during the detailed design stage of the Project. Disposal of Construction and Demolition (C&D) waste with not more than 30 % inert material is likely to be to NENT Landfill but could be to any of Hong Kong’s three strategic landfills.

9.2.29 In order to avoid dust or odour impacts, any vehicle leaving a works area carrying C&D waste or public fill should have their load covered. Vehicles should be routed as far as possible to avoid sensitive receivers in the area.

9.2.30 Where any good quality reusable topsoil is generated from site clearance works it can be stockpiled and used later in final landscaping works, thus saving on costs for such works and reducing transportation and environmental impacts of disposal. Some suitable material may also be generated from dredging of fishponds. This material can be mixed with the soil for landscaping. Stockpiles should be less than 2 m in height, formed to a safe angle of repose and hydroseeded or covered with tarpaulin to prevent erosion during the rainy season and to minimise dust generation.

Concrete Waste

9.2.31 Concrete is the main material likely to be used in the construction of the tunnel portals, viaduct section, foundations, stations and associated works. Of the volume of wet concrete supplied, it is assumed that approximately 3-5% of the concrete used will be lost to waste. Dry concrete waste will be sorted out from the other wastes and recycled for reuse or sorted for disposal at a public filling area e.g. Tseung Kwan O Area 137 and/or Tuen Mun Area 38, as agreed with CED. Shotcrete is expected to be used for slope stabilisation works. There may be some surplus or rejected shotcrete. The use of precast concrete segments for the tunnel lining and viaduct segments will significantly minimise the expected concrete waste.

General Works Waste

9.2.32 The following wastes will be generated during the construction of the railway track, tunnels and Lok Ma Chau station:

· Wooden materials from formwork and site fencing;

· Chemical waste - oils, lubricants, paints and solvents;

· Aqueous waste including biodegradable lubricant for the TBM cutter head;

· Slurries including bentonite slurries or similar grouts;

· Sewage; and

· Municipal waste.

Wooden materials, formwork and site fencing

9.2.33 Different kinds of wooden materials are essential to the construction project, such as wooden boards used as falsework and formwork for concrete structures, erection of site boundaries, as well as bamboo for scaffolding at the viaducts and stations. Wooden materials are important and valuable resources.

9.2.34 All wooden materials used on site should be kept separate from other wastes. Wooden boards can be reused on site although the reusability and quantity of final waste depends on the shape and quality of the boards. Boards used should be capable of being reused at least five times, thus keeping the wastage rate down to around 20 %. Timber which cannot be reused should be sorted and stored separately from all inert waste before being disposed of to landfill. On-site incineration of wooden waste requires a permit from EPD in accordance with Section 43 of the Air Pollution Control Ordinance (Cap. 311), Open Burning Regulation (1995). It is an offence under law to openly burn construction waste. A number of private contractors will collect used formwork materials for local reuse or export to China. On completion of the construction phase, the boards should be sorted and grouped then distributed to other construction sites.

9.2.35 Reusable steel shutters should be used as a preferred alternative to formwork and falsework where possible.

9.2.36 Site fencing may be necessary to separate the construction works from the public and to reduce construction nuisance such as noise to nearby sensitive receivers. In this case metal fencing or building panels to provide site fencing should be used. Timber hoarding is prohibited. Building panels are cement structures with a lightweight concrete core. The material provides good sound and thermal insulation, as well as being both waterproof and fire resistant. These panels are easily recycled and reduce wastage of metals.

Chemical Waste

9.2.37 Where the construction processes produce chemical waste, the Contractor must register with EPD as a Chemical Waste Producer. Wastes classified as chemical wastes are listed in the Waste Disposal (Chemical Waste) (General) Regulation. These wastes are subject to stringent disposal routes. EPD requires information on the particulars of the waste generation processes including the types of waste produced, their location, quantities and generation rates. A nominated contact person must be registered with EPD.

9.2.38 Storage, handling, transport and disposal of chemical waste should be arranged in accordance with the “Code of Practice on the Packaging Labelling and Storage of Chemical Wastes” published by EPD. Chemical waste should be collected by a licensed collector.

9.2.39 The major chemical waste types arising from the construction sites are likely to be oils, lubricants, paints and solvents. Oil waste may be in the form of raw waste, or as sundries such as spent oil filters, or materials used to absorb oil leaks. Various storage and disposal measures are recommended in the Code of Practice to minimise impacts from these chemical sources.

9.2.40 It is expected that the TBM cutter head lubricant will be a tensoactive and a polymer in aqueous solution (correspondence with Dragages, 29.09.2001). Both will be biodegradable and non-toxic substances and therefore this will not produce any chemical waste. Other lubricants including oil and grease will be generated though operation of the TBM but these will be kept within the TBM remote from the cutter head. All excavated materials will be treated on site to settle out the solid spoil in settlement basins. Water generated will be treated separately using flocculating agents to minimise turbidity in the discharge. There is unlikely to be any chemical contamination, due to the biodegradable nature of the cutter head lubricant. In addition, the tunnel spoil will be dewatered to avoid causing nuisance and pollution on transit and during disposal at public filling areas.

9.2.41 Hard standing impermeable surfaces draining via oil interceptors should be provided in works area compounds. Interceptors should be regularly emptied to prevent release of oil and grease into the surface water drainage system after accidental spillages. The interceptor should have a bypass to prevent flushing during periods of heavy rain. Oil and fuel bunkers should be bunded and/or enclosed on 3 sides to prevent discharge due to accidental spillages or unintentional discharge from tanks. Bunding should be of sufficient capacity to accommodate 110% of the volume of the largest container or 20% of the total volume of waste, whichever is greatest. Waste collected from any grease traps should be collected and disposed of by a licensed contractor.

9.2.42 Any construction plant which is likely to leak oil, should have absorbent inert material e.g. sand, placed beneath it. This material should be replaced on a regular basis and the contaminated material stored in a designated, secure place. Such relatively inert material is suitable for landfill disposal and can be disposed of via the normal waste stream.

9.2.43 Lubricants and waste oils are likely to be generated during the maintenance of vehicles and mechanical equipment. Used lubricants should be collected and stored in individual containers which are fully labelled in English and Chinese and stored in a designated secure place. If possible, such waste should be sent to oil recycling companies, and the empty oil drums collected by appropriate companies for reuse or refill. The Centre for Environmental Technology operates a Waste Exchange Scheme which can assist in finding receivers or buyers for chemical wastes.

9.2.44 Oil and lubricant wastes are classified as chemical wastes, and if not recycled, should be treated at the Chemical Waste Treatment Centre, Tsing Yi, or other sites licensed for the disposal of waste oil. A trip ticket system operates to control the movement of such chemical waste, and tickets have to be produced upon the request of EPD.

9.2.45 Some paints and solvents are classified as chemical waste and, if used on site, will be subject to the stringent requirements of the Waste Disposal (Chemical Waste) (General) Regulation. Empty paint cans should be recycled or collected as waste. Any dry paint waste should be swept up and collected in containers for disposal.

9.2.46 No lubricants, oils, solvents or paint products should be allowed to discharge into water courses, either by direct discharge, or as contaminants carried in surface water runoff from the construction site. Storage areas should have adequate ventilation and be covered to prevent rain entering.

9.2.47 Some bentonite will be used to support the cutting face during maintenance of the TBM. Whilst the recommendations of ProPECC PN 1/94 – Construction Site Drainage should be followed wherever possible for handling and disposal it will not be possible to re-use the bentonite slurry as it will be extracted along with rock waste when tunnelling resumes following each intervention period. In this case the bentonite will be mixed with rock and drained as usual before sending to the final disposal site.

Aqueous Wastes

9.2.48 Requirements designed to protect against surface runoff include the use of sediment traps, settlement ponds, special drainage channels and bunding. Discharges from concrete works will be high in suspended solids and pH. These washings must be settled in a sedimentation pit, and possibly treated to reduce pH before discharge. Oil interceptors should be used where oily wastes are present, and must have a bypass for ease of disposal of oily wastes. Landtake under stockpiles or open working areas must be minimised wherever practicable and the stockpiles should be fenced and bunded to reduce erosion and sediment release. Runoff from the stockpiles should be collected in sediment traps. Solids accumulated in the sand traps, settlement tanks, manholes, and stream beds must be cleared out regularly and disposed of accordingly in order to maintain an effective system.

9.2.49 Tunnel spoil is expected to be high in moisture content on excavation. Measures will be taken on site to reduce the moisture content and to remove any chemical additives which may have contaminated the water. De-watering of the spoil will also minimise nuisance and pollution in transit to public filling areas.

9.2.50 All discharged waters, including sewage and site runoff, should comply with the appropriate standards in the Technical Memorandum on Effluents Discharged into Drainage and Sewerage Systems, Inland and Coastal Waters, prior to discharge. Advice on the handling and disposal of construction site discharges, including site runoff and contaminated wastewaters, is provided in the ProPECC Paper (PN1/94), Construction Site Drainage.

Wheel wash waste

9.2.51 All vehicles leaving any of the works areas must pass through a wheelwash at the site access/exit. If, at any time, further entry/exit points are created, similar facilities must be provided. The wheelwash must be regularly cleaned to remove sediment, a process which may produce a large volume of wastewater. To prevent excess sedimentation, and minimise possible contamination of local streams and water courses, these wastewaters should be directed into settlement ponds as far as practicable. The wastewater can then be reused on site. The maintenance of the wheelwash will be the responsibility of the Contractor undertaking the site formation works.

9.2.52 If the waste water contains a significant amount of oil and grease from vehicles, areas of sand for absorbing oily wash water should be set up by contractors. Liaison with the Food and Environmental Hygiene Department (FEHD) is essential for correct disposal.

Sewage

9.2.53 Sewage is characterised by high BOD and suspended solids, is enriched with nutrients and has high bacteriological counts. Domestic sewage generated from any additional site toilets, washing facilities and any temporary canteen provided for construction workers should be collected separately and disposed of or appropriately treated to comply with Government requirements. It is the responsibility of the contractor to ensure that sewage disposal complies with the standards set out in the Technical Memorandum on Effluents Discharged into Drainage and Sewerage Systems, Inland and Coastal Waters. Sewage impacts and appropriate mitigation measures are dealt with in the Water Impact Assessment Chapter.

Municipal/Domestic Waste

9.2.54 Solid and liquid wastes will be generated by the construction workers during the clearance/construction period. The quantity of municipal waste generated is estimated to be 1.10 kg/employee/day (EPD, 1998). A temporary refuse collection station should be set up by the Contractor. Municipal waste should be collected regularly in black refuse bags and delivered to an approved Refuse Transfer Station or landfill as required.

9.2.55 Provision and collection of skips for different types of recyclable waste is the responsibility of the contractor. Arrangements should be made directly with the recycling companies, for example, the paper merchants, to collect the waste as required.

9.2.56 A summary of the solid waste arising as a result of the construction phase is presented in Table 9.6.

Table 9.6

Construction Wastes Arising as a Result of Proposed Works

*Area*	*Major Activities*	*Waste Type*	*Disposal*
Lok Ma Chau, Tunnel Portals, EAPs, Kwu Tung Station Box	Site clearance	Vegetation Topsoil Pond Material	Landfill Used for landscaping Used for landscaping
Kwu Tung, Western Tunnel Portal	Demolition	Concrete Bricks/Tiles Ferrous Metal Wooden and other non-inert waste	Public Filling Area Public Filling Area Recycle Landfill
Tunnel Kwu Tung Station Box Lok Ma Chau	Excavation	Fill Material Bentonite Contaminated concrete/soil Fish pond deposits Soil material	To Lok Ma Chau Station works area or Public Filling Area If sufficiently mixed with rock and drained of water to public filling area. To landfill Reuse within site for landscaping or mix with dry material
All, particularly works areas at Sheung Shui, Kwu Tung and Lok Ma Chau	General site Activities	Sewage wastes Municipal Wastes Packaging Materials Chemical Waste Oil	Treatment Landfill Landfill CWTP Licensed Contractor

Recycling or Re-use Facilities for Construction Wastes

9.2.57 As a result of the large variety of wastes which will be generated during the construction (and operation) of the Spur Line, the establishment of an efficient collection system is required to achieve environmental objectives. The system should also allow for recycling of certain materials and proper disposal of other materials as detailed in Table 9.7.

Table 9.7

Construction Waste types and their potential for recycling or re-use

Waste type	Works generating materials/waste	Volumes lost as waste	Potential re-use or recycling	Disposal Options
Fill material	Excavation of Kwu Tung Station Box and piling works	None	Excess fill material produced during piling/ boring activities will be-re-used for road formation and at Lok Ma Chau station	Most fill material will be disposed of to Public filling areas.
Tunnel Spoil	Tunnel boring		Approximately 50,000 m³ material can be used at Lok Ma Chau station and in other areas where a net import of fill is required	Majority of tunnel spoil to public filling area
Unsuitable fill material (fishpond muds)	Excavation at Lok Ma Chau	Small amounts	Dried and reused when mixed with other over dry materials	Where possible all should be reused within works. If the organic content is high material will not be suitable for disposal to a public filling area and a suitable location, as agreed with EPD should be used.
Concrete/ Asphalt	Road surfaces/ Demolition; Construction of stations	3 - 5 %	Needs to be separated; re-useable material needs to be crushed	To public filling area
Wood formwork, fencing	Construction of viaduct, EAPs, tunnel portals and stations. Demolition.	20 %	Used as lower grade shuttering or fencing on-site or other sites	To landfill (final disposal)
Reinforcing steel, steel cable and shutters	Construction of viaducts, EAPs, Tunnel Portals and stations Demolition	1 %	Most material can be re-used after cleaning Reinforcement off cuts to be scrapped/recycled
Chemical waste	General construction site activities	Small amounts	Recycling/disposal firms will collect chemicals or waste oil, or refill oil containers	Chemical waste, including paints disposed of to treatment facility - REQUIRES LICENSE
Oil waste				Oil can be removed for recycling or soaked up by sand for disposal to landfill.
Grease trap waste				Grease trap waste collected and disposed of by licensed contractor.
Wheel wash waste	Vehicle use during general works	Total volume when replaced	Recycling through filter until replacement of water is required	Onto sand area where natural filtration occurs, and oils can be retained before landfill disposal.
Sewage	Where site workers are present		None
Municipal/ Domestic waste	General site activities	Putrescible waste, wet paper, fabrics	Cans, bottles, dry paper	To landfill

Responsibilities for Construction Waste Management

9.2.58 The Contractor should incorporate recommendations into a comprehensive on-site waste management plan. This should include all factors dependent on individual works sites including designation of areas for the segregation and temporary storage of materials for future use or recycling. Such provision cannot be specified at this stage. Contractors should follow the recommendations of WBTC No. 29/2000 for on-site separation of waste.

9.2.59 The Public Fill Committee reviews and co-ordinates the provision and operation of public filling facilities. Responsibilities for recycling, re-use or disposal of waste materials are divided between the contractors generating the waste, FEHD, and the management of the receiving public filling sites. These responsibilities are described below and summarised in Table 9.8.

9.2.60 Under present practices, contractors handle their own wastes, often without separating different types of waste resulting in incorrect disposal of wastes. Under the proposed scheme, contractors would be required to separate wastes to ensure maximum reuse of materials and minimise adverse impact on the environment.

Concrete

9.2.61 The waste concrete generated during construction should be transported directly to the public filling area by the contractor. Separation is essential to enable concrete to be processed, for example, by crushing at the disposal site, and used as fill at other sites.

Wood formwork and steel

9.2.62 Waste material will be reused or recycled wherever possible and should be taken to landfill, either WENT or NENT depending on the origin of the waste material, only as a last resort. It should be separated from recyclable concrete. Contractors are responsible for storage of re-useable materials on site.

Chemical wastes and oil wastes

9.2.63 Contractors are responsible for registering as a chemical waste producer with EPD for the disposal of chemical and oil wastes. Chemical wastes should be collected by a licensed collector. A storage area should be designated as a pre-disposal containment area to prevent environmental impacts from spilt chemicals.

Wheel Wash Waste

9.2.64 Areas of sand for absorbing oily wash water should be set up by Contractors. Liaison with FEHD/EPD is essential for correct disposal.

9.2.65 While fulfilling the responsibilities described above, each contractor is required to maintain their works area in compliance with environmental requirements. The generation of dust and noise from concrete and other waste collection must be minimised in compliance with environmental objectives. Maintenance of a clean and tidy environment is essential to minimise adverse environmental and visual impact.

Table 9.8

Responsibilities for waste collection, recycling and

disposal during the Construction Phase

*Waste type*	*Responsibility for collection of waste*	*Responsibility for transport of waste off-site*	*Responsibility for recycling*	*Responsibility for disposal*
Fill material	Construction contractors required to stockpile excess fill for use elsewhere or disposal	Contractor	Recycled on site	Contractor
Unsuitable material (e.g. fishpond mud)	Construction Contractors required to collect for use elsewhere in the works	Contractor	Contractor responsible for transport from donor site to recipient site for re-use	Contractor
Concrete	Contractor – directly at source of waste generation	Contractor – in contractor’s vehicles to public filling area	CED (Port Works) defines suitable dumpsites. Project proponent of public filling area is responsible	Contractor
	Separation of re-useable and waste concrete should be carried out at source by contractor	Disposal of re-useable and waste concrete in different areas of filling area as required	Project proponent to provide different areas for re-useable and waste concrete as required
Wood formwork, fencing	Contractor – directly at source of waste generation where volumes are large	Contractor – transported in contractor’s vehicles to public filling area	Contractor - at source	Contractor to Landfill
	Separation of waste wood and concrete should be carried out at source by contractor	(inert material) or landfill (non-inert material)
Reinforcing steel, steel cable and shutters	Contractor – directly at source of waste generation where volumes are large	Contractor – transported in contractor’s vehicles scrap/recycling	Contractor - at source	Contractor to scrap/recycling
	Separation of waste steel and concrete should be carried out at source by contractor

9.3 Operational Waste

Introduction

9.3.1 Assessment of potential solid waste impacts arising from the operation of the Spur Line and stations at Sheung Shui and Lok Ma Chau, involves the following aspects:

(i) A characterisation of the waste generated from the Spur Line once operational.

(ii) The identification of feasible means for the collection, storage and handling of waste generated, for the purpose of disposal of the waste to existing and committed waste management facilities away from the Spur Line.

(iii) The identification and proposal of mitigation measures to ameliorate environmental impacts associated with the operation of the Spur Line and its stations.

9.3.2 The types of waste which will arise during the day-to-day operation of the Sheung Shui - Lok Ma Chau Spur Line can be broadly defined as :

· domestic/municipal waste;

· chemical waste; and

· screening waste/sludge from sewage treatment plant.

Municipal Waste

9.3.3 Municipal waste includes domestic waste, commercial waste and industrial waste. Domestic and commercial type wastes will be generated by the public and by employees and commercial operators at the stations. Such waste will include litter, foodstuffs, plastics, wood, office waste, cleaning materials and miscellaneous other waste produced during daily activities.

9.3.4 There will be approximately 1100 staff working at Lok Ma Chau Station when it begins operation in 2007. If the quantity of waste produced is assumed to be 1.26kg/employee per day based on the EPD linear regression equation (EPD, 1998), then the total generated waste requiring disposal is approximately 1,386 kg/day. The amount of municipal waste generated by the public using the Spur Line has been calculated based on quantities generated at Lo Wu (information received from KCRC 25 January 2000). Between 1,200kg/day and 2,300kg/day of municipal waste is expected to be generated by passengers at Lok Ma Chau station, based on passenger flows estimated in the Implementation Proposal to Government.

9.3.5 Provision of refuse skips, collection of refuse and the ultimate disposal of the refuse to a RTS or landfill will be the responsibility of KCRC and/or the cleaning contractor employed by KCRC.

9.3.6 Industrial type waste will arise from maintenance activities on both the railway and the stations and may include spent welding rods, ferrous metals and steel, glass and plastic. Waste generated by maintenance activities may be produced at any point along the alignment rather than at specific locations. Quantities of this type of waste are expected to be small.

9.3.7 To prevent industrial and maintenance waste from becoming a nuisance, a licensed waste collector should be employed to remove accumulated waste frequently and dispose of it accordingly. Those components that can be recycled should be separated and arrangements should be made with paper merchants and recycling companies to collect the wastes. A well implemented waste management hierarchy and good practice with respect to storage, transport and disposal, is expected to minimise the potential environmental impacts associated with waste production.

Chemical Waste

9.3.8 Chemical waste is defined under the Waste Disposal (Chemical Waste ) (General) Regulations as “ Any substance or thing being (a) scrap material, (b) effluent, or (c) an unwanted substance or by-product arising from the application of or in the course of any process in a trade activity, and which is or contains any substance or chemical specified in the prescribed schedule if such substance or chemical occurs in such form, quantity or concentration so as to cause pollution, constitute a danger to health or pose a risk of pollution to the environment.”

9.3.9 The main source of chemical waste will be during routine maintenance activities on the railway and the stations. The major chemical waste types arising from the operation of the Spur Line are likely to be lubricants, paints, used batteries, oil, acids and alkalis, pesticides and herbicides, coolants and solvents. Oil waste may be in the form of raw waste or as sundries such as spent oil filters, or materials used to absorb oil leaks.

9.3.10 Sediment will be collected from the sumps in the tunnels. This may be contaminated with oil and grease waste from track lubricants. As far as possible the contaminated sediment should be removed and disposed of whilst that not contaminated with oil and grease can be cleaned and re-used.

9.3.11 Routine servicing and maintenance of the Air Conditioning (A/C), Air Handling Units (AHU) and chiller plants at stations, in addition to A/C facilities in trains will generate some oil, grease, lubricants, cooler chemicals and germicides. These should not be allowed to discharge to water courses.

9.3.12 At grade sections, around stations, ventilation buildings and EAPs some herbicides and pesticides will be used to prevent the growth of nuisance vegetation. Use should be minimised to prevent disposal problems and minimise potentially contaminated run-off. Lubricants will also be used on the tracks to ease travel around bends and to reduce noise impacts. This will be magnified at the bends at Sheung Shui at the eastern tunnel portal and Chau Tau, close to Lok Ma Chau road.

9.3.13 The exact quantities of chemical waste that will be generated by the operation of the Spur Line are unknown at this stage but they are excepted to be small. Due to the potential environmental and health & safety hazard that these chemicals pose, they must be handled, stored and disposed of appropriately, in accordance with the Waste Disposal (Chemical Waste) (General) Regulations and the Code of Practice on Packaging, Labelling and Storage of Chemical Waste. Chemical waste that cannot be recycled should be treated at the Chemical Waste Treatment Centre, Tsing Yi, or at other sites licensed for the disposal of such wastes. Provided that these measures are strictly implemented, no significant impacts are predicted.

Sludge

9.3.14 Sludge generated from Lok Ma Chau station will be biologically treated using a sewage treatment plant, most likely, a Rotating Biological Contactor (RBC). The incoming raw sewage will first flow into a coarse bar screen to remove large debris prior to pre-treatment. The pre-treated sewage is then pumped at a constant rate to a fine bar screen where small debris is removed. The screenings collected by both the coarse and fine screens will be collected in plastic bags and disposed of as solid waste. Only a small amount of screening waste is expected.

9.3.15 Based on the design daily flow of 1,228 m³ per day (with an estimated BOD loading of 760 kg per day) and a sludge yield of 0.45, the amount of waste sludge generated by an RBC is estimated to be around 342 kg per day. The sludge will be treated and dewatered on-site before disposal, using appropriate dewatering equipment to achieve the 30% solids requirement for landfilling. This will reduce the volume of sludge by about 80 percent. Since the amount of sludge generated is not large, the treated sludge can be collected in plastic bags and disposed of as solid waste in landfill or other approved disposal ground. Suitable containers should be provided for the storage of the sludge. Care should be taken to avoid any accidental leakage or spillage of the sludge. EPD/DSD should be consulted to ensure that sludge meets their requirements prior to any discharge.

Table 9.9

Summary of Potential Waste Types and

Disposal Options during Operational Phase

Major Activities	Waste Type	Disposal
Operation of Stations	Sewage Municipal Waste	Sewage Treatment Landfill/Recycling
Maintenance of track and stations	Industrial waste Waste oil and lubricants Chemical Waste	Landfill/recycling CWTC* Licensed contractor
Routine Servicing of A/C, AHU, train carriages etc.	Chemical waste Waste oil	CWTC Licensed contractor
Sewage Treatment	Sludge	Landfill or other approved disposal site

* Chemical Waste Treatment Centre, Tsing Yi

Recycling or Re-use Facilities

9.3.16 Municipal waste recycling is stated to be one of the main requirements to achieve the objectives of the Waste Reduction Study for Hong Kong, which lead to the generation of the Waste Reduction Framework Plan (WRFP) (EPD, 1998). The new stations should be designed to incorporate maximum recycling facilities. Clearly marked out bins should be provided for individual waste types. Eye-catching designs can be used to indicate waste bins to be used for plastics, paper, cans, glass and other waste types. In addition, public awareness of the recycling facilities can be raised through publicity campaigns not only around the stations but also on the trains themselves.

9.3.17 Using a public awareness scheme also has financial incentives for KCRC or their appointed waste contractor through minimisation of disposal costs. The WRFP is expected to introduce taxation measures and charges to waste producers. The costs of waste management will be significantly reduced through the maximisation of recycling process rather than standard disposal routes via RTS or direct to landfill.

9.3.18 Re-use of both ferrous and non ferrous metals, wood, oils and other materials used in maintenance of equipment, stations and track should also be incorporated wherever possible. Recycling and waste recovery of such materials should be the next stage where re-use is no longer possible.

Responsibilities for Waste Management

9.3.19 Responsibility for re-use, recycling or disposal of materials is described below. Once details of location etc. are finalised KCRC should incorporate recommendations of the EIA into a fully comprehensive waste management plan for the Spurline.

Municipal Waste

9.3.20 Under current practices the provision of refuse bins at stations is the responsibility of KCRC and the collection of refuse is the responsibility of their waste/cleaning contractors. Under the WRFP, both parties should take note of Chapter 7: Action for the Private Sector which outlines ways of reducing waste and managing it more efficiently.

9.3.21 Arrangements should be made with recycling companies for the collection of paper, plastics, glass and all other recycled materials.

Chemical Waste

9.3.22 The contractors involved in the servicing and maintenance of the air conditioning, air handling unit and chiller plant are responsible for obtaining licences for the handling, storage and disposal of chemical and oil wastes. If required, a storage area should be designed as a pre-disposal containment area to prevent environmental impact from these chemicals.

Sludge

9.3.23 The ultimate responsibility of the sewage treatment plant will be the users (KCRC or an appointed contractor). Sludge generated from the treatment of sewage should be treated and properly stored on site and disposed of at a designated landfill or other approved site.

9.4 Other Projects in the Study Area

9.4.1 The recently publicised Kwu Tung NDA under the NENT Planning and Development Study will also have impacts on waste production in the area. The EIA for the NENT Study is still ongoing. Both the findings of the Spur Line EIA, and those of the NENT Study, when completed, should be taken into account when formulating both Waste Management Plans. Both projects should implement suitable environmentally and economically sustainable management systems to minimise environmental impacts.

9.4.2 The programme for implementation of the proposed Kwu Tung Norht NDA is still under review. At this stage, the overlap with Spur Line is uncertain. However, as the initial works contracts for Kwu Tung North NDA will require a significant amount of fill material, the feasibility of utilizing material generated by Spur Line should be considered at a later stage. The suitability of the tunnel spoil generated and the feasibility of storing this material for use in the NENT project area should be further discussed with CED in order that transport and import/export costs can be kept down on both Projects and that the fill from Spur Line can be beneficially re-used.

9.5 Summary

9.5.1 A variety of waste materials will be generated during construction and operation of the Spur Line. Waste types and quantities have been estimated as far as possible and mitigation measures evaluated in terms of the avoidance-minimisation-recycling-disposal hierarchy recommended by Government.

9.5.2 Construction phase surplus material includes material from excavation of fishponds and rock excavated during tunnelling activities, excavation of the station box and viaduct foundations. Inert materials such as concrete and steel should be separated from excavated earth and wooden formwork that can be re-used on site. Other excavated materials such as fishpond bund material can be used in the wetland compensation area, while some of the tunnel spoil comprising rock can be re-used along the tunnel alignment, and during the filling operation at Lok Ma Chau Station, providing programme constraints allow. This should be determined when the detailed programme for each contract is formulated. Additional fill material will be required for Lok Ma Chau station. Some tunnel spoil will be re-used to backfill cut and cover sections and the Kwu Tung station box. However, this is likely to be small, and surplus tunnel spoil which is not suitable for re-use in the works will be beneficially re-used in public filling areas, subject to the conclusion of discussions with CED.

9.5.3 Good working practices will minimise potential impacts which arise from the production of general works waste. Measures which should be taken are described below:

(i) Waste should be characterised and appropriately disposed of

(ii) Stockpiles should be protected from erosion.

(iii) Vehicles carrying unsuitable material should have their loads covered and be routed to avoid sensitive receivers.

(iv) Wastewater should be appropriately collected and treated.

(v) Chemicals should be correctly stored and recycled where possible.

(vi) Recycling should be practiced wherever possible.

(vii) All wastes should be collected at regular intervals to keep the site tidy.

9.5.4 In addition, the following steps will be taken to ensure waste characterisation and quantification on site:

(i) KCRC, or the main contractor, should act as the overall co-ordinator for the management of waste. It is important as it can minimise the disposal of C&DM off-site, especially there is opportunity for the transfer or excavated material from one portion to another portion of the project. An overall waste management plan should be prepared by this party and submitted to EPD for review and incorporation of his comments into the WMP to his satisfaction before the commencement of construction is required.

(ii) the contractor shall record the amount of waste-generated, recycled and disposed of (including the disposal sites).

(iii) the contractor shall use a trip ticket system in accordance with WBTC 5/99 for the disposal of C&D materials to any designated public filling facility and/or landfill.

(iv) training shall be provided for workers about the concepts of site cleanliness and appropriate waste management procedure, including waste reduction, reuse and recycling.

9.5.5 During operation, the main wastes generated will be domestic refuse and sludge from the sewage treatment plant on site. Refuse should be collected through an appropriate system of waste disposal facilities, with recycling implemented where feasible. Sludge will be dewatered before disposal to landfill. Chemical wastes require correct storage, handling and disposal to minimise potential impacts on the environment.

9.5.6 Implementation of an efficient waste management strategy based on the recommendations provided in this chapter will minimise potential impacts from the generation storage, handling, transport and disposal of wastes arising from the Spur Line Project.

REFERENCES

ProPECC PN 1/94 Environmental Protection Department Practice note for Professional Persons: Construction Site Drainage.

EPD (1998). Waste Reduction Framework Plan, 1998-2007. Planning, Environment and Lands Bureau.

EPD (1992). Code of Practice on one Packaging, Labelling and Storage of Chemical Wastes.

KCRC (16 October 2001) PFC Paper No. 5/2001 Management of Construction and Demolition Materials

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Works Area	Estimated Date of Works	Fill material required from re-use or import (m³)	Material generated (m³)	Balance	Potential source of material if required
Lok Ma Chau Station	Tentatively Early 2003 to Mid 2006	700,000 required, of which 4,000 is rockfill for haul road construction, 300,000 CDG fill material for station and 90,000 is for filling of fishponds. All remaining material required is for site formation.	Fishpond material to be excavated to allow for site formation. 24,000, other excavated material for infrastructure 20,000	Material to be brought in for surcharge. Material will need to be brought in by barge to supply the deficit.	Rockfill from tunnel boring may be used in site formation if programme constraints allow. Most material brought in will be sand fill material and imported public fill from a designated source. Some fishpond material may be used in the creation of the marsh wetland compensation area to the south of the station. This re-use depends on sediment quality, to be determined through chemical analysis. The remainder of the fishpond material to be drained and disposed of according to WBTC 22/92.
Western Tunnel Portal, Approach and TBM Recovery Shaft	May 2002 to Sept 2004	41,000	184,500 May include some contaminated material	Some of the material for road formation can be obtained from the surcharge discarded from the tunnel portal site formation.
Eastern Tunnel Portal, Approach and TBM launching shaft	May 2002 to Feb 2006	41,000	295,000
Tunnel Boring	June 2003 to Oct 2005	-	390,000	Some of material generated may be used in remainder of alignment if required for road formation and site formation.
Kwu Tung Station Box	Jan 2003 to Apr 2006	18,000	Some contaminated material may have to be removed from the surface areas. This should be tested and treated on site or disposed of to landfill, provided TCLP limits are met. Total excavated material 256,000	Some material excavated can be re-used for backfilling the station box.	The quantity to be re-used depends on the contamination status. Contaminated material to be remediated on site or disposed of to landfill.-
EAPs (Western, Eastern and Viaduct)	W: Jan 2003 to Mar 2005 E: Jan 2005 to Oct 2005	5,000	Some vegetation removal, potentially some contaminated land – total excavated material 14,000	Some of the material for road formation can be obtained from the surcharged discarded from the station site formation. Remaining volume to be brought in from outside.	-
Foundations for viaduct columns and other works in viaduct section	Dec 2002 to June 2005	20,000	Some vegetation and possible contaminated land, 34,500