8 waste management implications

8.1 Introduction

8.1.1 This section identifies the types of wastes that are likely to be generated during the construction and operational phases of the Project and evaluates the potential environmental impacts that may result from handling, transport and disposal of the wastes.

8.1.2 Mitigation measures and good site practices, including waste handling, storage, collection and disposal, have been recommended with reference to the applicable waste legislation and guidelines. Handling and disposal of sediments are also discussed in this section.

8.2 Environmental Legislation, Standards and Guidelines

8.2.1 The waste management implications have been assessed in accordance with the requirements outlined in Annex 7 and Annex 15 of the Technical Memorandum on Environmental Impact Assessment Process (EIAO-TM) and the EIA Study Brief (No. ESB-346/2021).

8.2.2 The relevant legislation, standards and guidelines applicable to the present study for the assessment of sediment and waste management implications include:

· Waste Disposal Ordinance (Cap.354) and subsidiary Regulations;

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

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

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

· Public Health and Municipal Services Ordinance (Cap.132) – Public Cleansing and Prevention of Nuisances Regulation;

· Dumping at Sea Ordinance (Cap.466); and

· Practice Note for Authorized Persons and Registered Structural Engineers on Management Framework for Disposal of Dredged/ Excavated Sediment (PNAP ADV-21).

Criteria and Guidelines for Evaluating and Assessing Waste Management Implications as specified in Annexes 7 and 15 of the EIAO-TM

8.2.3 Annex 7 of the EIAO-TM describes the criteria for assessing waste management implication which include provision of adequate waste handling, storage, collection, transfer, treatment and disposal facilities during both construction and operational phases, provision of adequate facilities to facilitate waste reduction, exploration of beneficial use of waste generated as well as alternatives which generate minimal amount of waste.

8.2.4 Annex 15 of the EIAO-TM describes the approaches and methodologies for assessment of waste management implications arising from the project.

Waste Disposal Ordinance

8.2.5 The Waste Disposal Ordinance (WDO) prohibits any unauthorised disposal of wastes. Construction waste, defined under Cap. 354N of the WDO, refers to a substance, matter or thing which is generated from construction works. It includes all abandoned materials, whether processed or stockpiled or not, before being abandoned, but does not include sludge, screenings or matter removed or generated from desludging, desilting or dredging works.

8.2.6 Under the WDO, wastes can only be disposed of at designated waste disposal facilities licensed by Environmental Protection Department (EPD). Breach of this Ordinance can lead to a fine and/or imprisonment. The WDO also stipulates the requirements for issuing licenses for the collection and transportation of wastes.

Waste Disposal (Chemical Waste) (General) Regulation

8.2.7 Under the WDO, the Waste Disposal (Chemical Waste) (General) Regulation provides regulations for chemical waste control, and administers the possession, storage, collection, transport and disposal of chemical wastes. EPD has also issued a ‘guideline’ document, the Code of Practice on the Packaging, Labelling and Storage of Chemical Wastes (1992), which details how the Contractor should comply with the regulations on chemical wastes.

Waste Disposal (Charges for Disposal of Construction Waste) Regulation

8.2.8 Under the Waste Disposal (Charges for Disposal of Construction Waste) Regulation, construction waste delivered to a landfill for disposal must not contain more than 50% by weight of inert material. Construction waste delivered to a sorting facility for disposal must contain more than 50% by weight of inert material, and construction waste delivered to a Public Fill Reception Facilities for disposal must consist entirely of inert material.

Land (Miscellaneous Provisions) Ordinance

8.2.9 The inert portion of construction and demolition (C&D) materials may be taken to public filling facilities including public filling area, public filling barging points and stockpiling areas. This ordinance requires Dumping Licenses (to be issued by Civil and Engineering Development Department (CEDD)) to be obtained by individuals or companies, who deliver inert C&D materials to the public filling facilities.

8.2.10 Individual licenses and windscreen stickers are issued for each vehicle involved. Public filling areas will accept only inert building debris, soil, rock and broken concrete. The material should, however, be free from marine mud, household refuse, plastic, metal, individual and chemical wastes, animal and vegetable matters and any other materials considered unsuitable by the Filling Supervisor.

Public Health and Municipal Services Ordinance and Public Cleansing and Prevention of Nuisances Regulation

8.2.11 This regulation provides control on illegal tipping of wastes on unauthorised (unlicensed) sites.

Construction & Demolition Material Management Plan (C&DMMP)

8.2.12 Measures have been introduced under Section 4.1.3 of the Project Administrative Handbook for Civil Engineering Works (2022 Edition) published by CEDD to enhance the management of C&D materials and to minimise their generation at source. The enhancement measures include (i) drawing up a Construction and Demolition Material Management Plan (C&DMMP) at an early design stage to minimise C&D materials generation and encourage proper management of such materials; (ii) vetting of the C&DMMP prior to upgrading of the project to Category A in the Public Works Programme; and (iii) providing the Contractor with information from the C&DMMP in order to facilitate the preparation of the Waste Management Plan (WMP) and to minimise C&D materials generation during construction. Projects generating less than 50,000m³ C&D materials or importing less than 50,000m³ of fill material are exempted from the C&DMMP. If the C&DMMP is required of the Project, it should be prepared and submitted to Public Fill Committee (PFC) for in-principle approval prior to commencement of the detailed design.

8.2.13 ETWB TCW No. 19/2005, Environmental Management on Construction Site, sets out the policy, procedures and requirements for contractor to prepare and implement an Environmental Management Plan for on-site sorting and waste reduction of C&D materials.

Dumping at Sea Ordinance

8.2.14 According to the Dumping at Sea Ordinance, a permit from EPD is required if any waste producer intend to dump materials from vessels to designated marine dumping areas. The Authority will consider a number of factors including sources and nature of materials to be dumped, dumping rates, need for inspection / testing, water pollution avoidance measures etc before determining whether such a permit would be granted and, where deemed necessary, any conditions to be complied with. Breach of the requirements in the permit would result in a fine and/or to imprisonment.

Practice Note for Authorized Persons and Registered Structural Engineers on Management Framework for Disposal of Dredged/ Excavated Sediment (PNAP ADV-21)

8.2.15 PNAP ADV-21 sets out the procedure for seeking approval to dredge/ excavate sediment and the management framework for marine disposal of such sediment. It outlines the requirements for sediment quality assessment and provides guidelines for the classification of sediment based on their contaminant levels. It also explains the disposal arrangement for the classified sediment.

Other Relevant Guidelines

8.2.16 Other documents and guidelines related to waste management and disposal are summarised in Table 8.1.

Table 8.1 Other Relevant Documents and Information

Bureau / Department	Documents / Guidelines / Technical Circulars
Development Bureau	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 Project WBTC No. 19/2001, Metallic Site Hoardings and Signboards WBTC No. 12/2002, Specification Facilitating the Use of Recycled Aggregates DEVB TCW No. 06/2010, Trip-ticket System for Disposal of Construction and Demolition Material DEVB TCW No. 08/2010, Enhanced Specification for Site Cleanliness and Tidiness DEVB TCW No. 09/2011, Enhanced Control Measures for Management of Public Fill ETWB TCW No. 19/2005, Environmental Management on Construction Sites
Building Department	ADV-19, Practice Note for Authorized Persons and Registered Structural Engineers on Construction and Demolition Waste
CEDD	Project Administrative Handbook for Civil Engineering Works CEDD TC No. 11/2019, Management of Construction and Demolition Materials
Environment and Ecology Bureau	A Guide to the Chemical Waste Control Scheme A Guide to the Registration of Chemical Waste Producers Code of Practice on the Packaging, Labelling and Storage of Chemical Wastes Monitoring of Solid Waste in Hong Kong 2021

8.3 Description of Environment

8.3.1 The Project covers an area from KSR(NOL) Station to KTU(NOL) Station which is predominantly rural in character. The area has a mixed urban-rural character which is predominantly occupied by low-density residential and village developments with some brownfield operations.

8.3.2 The existing solid waste arising from the Project area includes domestic waste generated from village houses, commercial and industrial waste generated from open storage and industrial areas and chemical waste generated from vehicle maintenance workshop , open area storage and recycling facilities.

8.4 Identification and Evaluation of Wastes Implications

Assessment Methodology

8.4.1 The assessment of waste management implications from handling, storage, collection, transportation and disposal of solid waste materials generated by the landuse proposals have been undertaken in accordance with Annexes 7 and 15 of the EIAO-TM.

8.4.2 The waste management hierarchy was applied in the assessment and development of mitigation measures for waste. The waste management hierarchy is a concept which shows the desirability of various waste management methods and comprises the following in descending order of preference:

· avoidance;

· minimisation;

· recycling/reuse;

· treatment; and

· disposal.

8.4.3 All opportunities for avoiding, reducing, reusing and recycling of were explored based upon the following factors:

· avoiding or minimising waste generation throughout design, construction and operational phases;

· adopting better management practices to promote segregation materials;

· reuse and recycling on site or other projects; and

· diverting inert construction and demolition materials to public fills as far as possible.

Construction Phase

8.4.4 The construction activities to be carried out for the Project would generate a variety of wastes that can be divided into distinct categories based on their composition and ultimate method of disposal. The following waste types are anticipated to be generated:

· Construction and demolition (C&D) materials;

· General refuse;

· Chemical wastes; and

· Land-based sediments.

8.4.5 The construction works for the Project would tentatively commence in Q2 2025. Major construction activities and the associated waste generation are summarised in Table 8.2.

Table 8.2 Summary of Waste to be Generated during Construction Phase

Major Construction Activities	Potential Types of Waste to be Generated
· Site clearance; · Diaphragm wall construction at KSR(NOL), AUT, NTM, SAT and KTU(NOL) stations; · Temporary cofferdam walls for construction of ancillary buildings, cut-and-cover tunnels (i.e. KSR(NOL) overrun tunnel), new buildings and retaining walls in NTD; · Foundation construction for all buildings/structures and retaining walls; · Bulk excavation from ground level to formation levels of all stations, ancillary buildings, cut-and-cover tunnels⁽¹⁾ (i.e. KSR(NOL) overrun tunnel), buildings in NTD; · Site formation works at NTD and KTU(NOL) Station; · Excavation for adits from ancillary buildings to tunnel; and · Excavation for TBM tunnels⁽¹⁾ and mined tunnels⁽¹⁾.	· C&D materials · Chemical waste · General refuse
· Excavation at SMA, AUT Station, NTM Station, SAT Station and SNA.	· Land-based sediment

Major Construction Activities

Potential Types of Waste to be Generated

· Site clearance;

· Diaphragm wall construction at KSR(NOL), AUT, NTM, SAT and KTU(NOL) stations;

· Temporary cofferdam walls for construction of ancillary buildings, cut-and-cover tunnels (i.e. KSR(NOL) overrun tunnel), new buildings and retaining walls in NTD;

· Foundation construction for all buildings/structures and retaining walls;

· Bulk excavation from ground level to formation levels of all stations, ancillary buildings, cut-and-cover tunnels⁽¹⁾ (i.e. KSR(NOL) overrun tunnel), buildings in NTD;

· Site formation works at NTD and KTU(NOL) Station;

· Excavation for adits from ancillary buildings to tunnel; and

· Excavation for TBM tunnels⁽¹⁾ and mined tunnels⁽¹⁾.

· C&D materials

· Chemical waste

· General refuse

· Excavation at SMA, AUT Station, NTM Station, SAT Station and SNA.

· Land-based sediment

Note:

(1) The extent of each tunnel types (i.e. TBM tunnels, drill-and-blast tunnels, mined tunnels, and cut-and-cover tunnels) is shown in the Figure No. C1603/C/NOL/ACM/M50/305. The tentative construction programme of tunnels is also shown in Appendix 2.2.

Construction and Demolition Materials

8.4.6 C&D materials would be generated from excavation, demolition works, site formation, construction of facilities and station. These C&D materials comprise both inert (e.g. rocks, soil, broken concrete, building debris etc.) and non-inert components (e.g. vegetation and timber etc.).

8.4.7 The design, general layout, construction methods and programme adopted for the Project has minimised the generation of waste. In view of the site constraints, scale and nature of the Project, the available options for the construction of NOL are limited. Generation of C&D materials has been minimized as far as possible through utilisation of TBM and mined tunnelling methods for the tunnel construction instead of open cut or cut-and-cover method for reduction of C&D materials.

8.4.8 Majority of the C&D materials comes from the cut-and-cover construction of stations, ancillary buildings, NTD and part of the tunnel sections. Possible measures during design development to minimise the generation of C&D materials include:

· Optimisation of the overall size of station footprint through effective structural scheming and station planning to allocate plant equipment at ground level; and

· Optimisation of tunnel alignment to minimise excavation depth of cut and cover construction.

8.4.9 Summary of estimated amount of inert and non-inert C&D materials to be generated during construction phase and their estimated yearly amount are shown in Table 8.3 and Table 8.4 respectively.

Table 8.3 Summary of Estimated Amount of Inert and non-inert C&D Materials during Construction Phase

Activities	Approximate Quantities of Inert and Non-inert C&D Materials to be Generated (m³)⁽⁷⁾⁽⁸⁾
	Inert C&D Materials⁽¹⁾			Non-inert C&D Materials⁽⁴⁾
	Soft Inert Material⁽²⁾	Rock	Artificial Hard Material⁽³⁾	Non-inert C&D Materials⁽⁴⁾
KSR(NOL) Station	217,920	10,730	6,820	9,720
AUT Station	217,490	-	14,560	5,710
NTM Station	268,790	-	19,100	6,620
SAT Station	1,001,260	-	44,080	39,190
KTU(NOL) Station	412,000	3,000	8,000	24,000
TBM Tunnels ⁽⁵⁾	600,910	135,430	-	-
Mined Tunnels ⁽⁵⁾⁽⁶⁾	6,450	49,340	-	-
Cut and Cover Tunnels ⁽⁵⁾	194,390	71,420	270	4,860
Ancillary Buildings	255,500	161,890	10,760	15,400
NTD	500,630	-	62,910	19,750
*Total*	*3,67*5,340	431,810	*166,500*	*125,250*
Disposal Outlet ⁽⁸⁾	To be delivered to Tuen Mun Area 38 Fill Bank for off-site reuse⁽⁹⁾			Designated Landfill Site ⁽⁴⁾ to be agreed with EPD/CEDD

Notes:

(1) “Inert C&D Material”, also known as public fill, includes debris, rubble, earth, concrete and TBM excavated spoil after treatment to remove the bentonite slurry which is suitable for land reclamation and site formation.

(2) “Soft Inert C&D Material” mainly refers to excavated soil, etc.

(3) “Artificial Hard Material” (AHM) includes, but not limited to, broken concrete, asphalt, steel waste, bitumen, granular materials, debris, and rubble, etc.

(4) “Non-inert C&D Materials” involved in the Project include top soil, vegetation, timber and steel. In contrast to public fill, non-inert C&D materials, which is not suitable for land reclamation and subject to recovery of reusable/ recyclable items (e.g. timber to be delivered to Yard Waste Recycling Centre in Y-Park, steel to be collected by recycler), is disposed of at landfills.

(5) The extent of each tunnel types (i.e. TBM tunnels, drill-and-blast tunnels, mined tunnels, and cut-and-cover tunnels) is shown in the Figure No. C1603/C/NOL/ACM/M50/305. The tentative construction programme of tunnels is also provided in Appendix 2.2.

(6) Mined tunnels is required for the NTD connecting tracks, which include drill-and-blast method for tunnel section.

(7) In-situ volume is used.

(8) The estimated amount of waste has been rounded up.

(9) The disposal site of inert C&D materials is subject to the designation by the Public Fill Committee according to DEVB TC(W) No. 6/2010.

Table 8.4 Summary of Yearly Estimated Amount of Inert and non-inert C&D Materials during Construction Phase

C&D Materials		Approximate Quantities of Inert and Non-inert C&D Material to be Generated, m^{3 (5)(6)}
C&D Materials		2025	2026	2027	2028	2029	2030	2031	2032	2033	*Total*
Inert C&D Materials ⁽¹⁾	Soft Inert Material ⁽³⁾	14,700	141,680	932,710	1,160,600	1,130,970	291,500	3,180	-	-	*3,675,340*
	Rock	2,130	4,780	9,730	182,760	186,440	45,970	-	-	-	*431,810*
	AHM⁽⁴⁾	3,990	40,290	114,580	3,640	1,000	1,000	2,000	-	-	*166,500*
Non-inert C&D Materials ⁽²⁾		9,390	17,810	44,170	9,090	21,510	15,560	5,720	-	2,000	*125,250*
*Total*		*30,210*	*204,560*	*1,101,190*	*1,356,090*	*1,339,920*	*354,030*	*10,900*	0	*2,000*	4,*398,900*

Notes:

(2) “Non-inert C&D Materials” involved in the Project include top soil, vegetation, timber and steel. In contrast to public fill, non-inert C&D materials, which is not suitable for land reclamation and subject to recovery of reusable/ recyclable items (e.g. timber to be delivered to Yard Waste Recycling Centre in Y-Park, steel to be collected by recycler), is disposed of at landfills.

(3) “Soft Inert C&D Material” mainly refers to excavated soil, etc.

(4) “AHM” includes, but not limited to, broken concrete, asphalt, steel waste, bitumen, granular materials, debris, and rubble, etc.

(5) In-situ volume is used.

(6) The estimated amount of waste has been rounded up.

8.4.10 It is envisaged that bentonite slurry would be used as drilling fluid during TBM tunnelling works. The slurry is normally recycled and reused during the drilling process such that there will be no wastewater generated. The storage, treatment and recycling of the bentonite slurry will mainly be conducted at the slurry treatment plant. The TBM excavated spoil after treatment to remove the bentonite slurry will be delivered to Public Fill Reception Facility (PFRF) as normal spoil. The waste and wastewater generated, if any, will be handled in accordance with the WDO and Water Pollution Control Ordinance (WPCO). The detailed arrangement of the bentonite slurry treatment will be further reviewed and designed by the Contractor subject to the site condition and detailed construction methods.

8.4.11 Non-inert C&D materials generated would be reused and recycled as much as possible before disposal of at designated landfill site to be agreed with EPD/CEDD.

Fill Requirements

8.4.12 For NOL construction, earth filling activities include backfilling excavation above the stations and ancillary buildings, roadworks, site formation in northern portion of NTD to permanent formation level. General fill materials in compliance with specification will be used.

8.4.13 Earth filling activities will take place mostly between Years 2026 and 2033 based on the initial construction programme.

8.4.14 The construction programme adopted for the Project has already been adjusted to minimise the generation of waste including inert C&D materials. At this stage, re-use of all excavated soil materials for backfilling within the same sites is limited due to lack of stockpiling area and programme mis-match. However, parts of the excavated soil from this project can be potentially reused as backfilling materials in SAT station and NTD formation of platform subject to further review of the construction sequence, works programme and availability of the works sites/works areas for the NOL Main Line to be carried out in the next detailed design stage. At the meanwhile, the liaison for intake schedules of the potential reception sites was ongoing to explore the opportunity for reuse of C&D materials in other projects and is expected to be continued in the next design stage. Therefore, taking into account the limited availability of temporary stockpiling area on site and programme mis-match, surplus materials will be delivered to PFRF for off-site reuse while the backfilling materials will be imported.

8.4.15 Summary of estimated amount of imported fill required for the construction works is about 509,220m³ and is summarised in Table 8.5 and Table 8.6. Nevertheless, this amount of imported filling materials should be consulted with Fill Management Division of CEDD.

Table 8.5 Summary of Estimated Amount of Imported Fill Required

Activities	Approximate Quantities of Imported Fill Required, m³⁽¹⁾
KSR(NOL) Station	5,270
AUT Station	32,590
NTM Station	30,450
SAT Station	195,500
KTU(NOL) Station	63,880
Cut and Cover Tunnels	117,580
NTD	63,950
*Total*	509,220

Note:

(1) The estimated amount has been rounded up.

Table 8.6 Summary of Yearly Estimated Amount of Imported Fill Required

Type	Approximate Quantities of Public Fill Materials, m³⁽¹⁾
Type	2026	2027	2028	2029	2030	2031	2032	2033	*Total*
Fill Material	18,110	116,170	170	125,460	92,270	145,890	0	11,150	*509,220*

Note:

(1) The estimated amount has been rounded up.

Chemical Waste

8.4.16 Materials classified as chemical waste are listed in the Waste Disposal (Chemical Waste) (General) Regulation. The main chemical waste types arising from the construction of the Project may include the following:

· Scrap batteries;

· Spent hydraulic oils and waste fuel;

· Spent lubrication oils and cleaning fluids from mechanical machinery; and

· Spent solvent from equipment cleaning activities.

8.4.17 Chemical waste may pose the following environmental, health and safety hazards if not stored and disposed of appropriately:

· Toxic effects to workers;

· Adverse effects on water and land from spills; and

· Fire hazards.

8.4.18 It is difficult to quantify the amount of chemical waste as it will be highly dependent on the Contractor’s on-site maintenance practice and the quantities of plant and vehicles utilised. Nevertheless, it is anticipated that the quantity of chemical waste, such as lubricating oil and solvent produced from plant maintenance, will be in the order of few hundred litres per month.

8.4.19 The estimated amount of chemical waste to be generated during construction phase is summarised in Table 8.7.

Table 8.7 Summary of Estimated Amount of Chemical Waste to be Generated during Construction Phase

Activities	Estimated Amount of Chemical Waste to be Generated
Scrap Batteries	A few hundred kilograms per month
Spent Hydraulic Oil and Waste Fuel	A few hundred litres per month
Spent Lubrication Oil and Cleaning Fluids
Spent Solvent

8.4.20 Storage and handling of chemical waste should be arranged in accordance with the Code of Practice on the Packaging, Labelling and Storage of Chemical Waste published by the EPD. Chemical waste should be collected by a licensed collector and to be disposed of at a licensed chemical waste treatment and disposal facility. Wherever possible, opportunities for the reuse and recycling of materials will be taken.

8.4.21 Mitigation measures for chemical wastes are detailed in Section 8.5. Provided that the handling, storage and disposal of chemical wastes are in accordance with these requirements, adverse environmental impacts are not expected.

General Refuse

8.4.22 The construction workers would generate refuse comprising of food waste, wastepaper, aluminium cans and plastic bottles during the construction period.

8.4.23 The improper storage of general refuse may give rise to adverse environmental impacts. These could include water quality, odour, environmental hygiene concerns and visual impact in the form of windblown litter. The construction site may also attract pests and vermin if the storage areas are not well maintained and cleaned regularly. In addition, disposal of waste at sites other than the approved disposal facilities could also lead to similar adverse impacts at those sites.

8.4.24 During the construction phase, the peak number of workers would be about 38,190 worker in Year 2028. Based on the generation rate of 0.65 kg/person/day, the total refuse generated per day would be about 24,820 kg at peak time. It is estimated that approximately 31,990 tons of total general refuse would be generated for works sites/ areas throughout construction phase.

8.4.25 Summary of yearly estimated amount of general refuse to be generated during construction phase is summarised in Table 8.8.

Table 8.8 Summary of Yearly Estimated Amount of General Refuse during Construction Phase

Type	Year										*Total*
Type	2025	2026	2027	2028	2029	2030	2031	2032	2033	2034
Estimated Amount of General Refuse to be Generated, tons⁽¹⁾⁽²⁾	400	1,250	4,470	7,450	5,640	4,180	3,360	3,450	1,560	230	*31,990*

Notes:

(1) 25 working days per month has been assumed.

(2) The estimated amount has been rounded up.

8.4.26 In order to minimise the final disposal quantities of general refuse, provisions of recycle bins for different types of recyclable waste should be provided together with a general refuse bin. Arrangements should be made with the recycling companies to collect the recycle waste as required. The Contractor should provide training for workers relating to avoiding, reducing, reusing and recycling general waste. Participation in a local collection scheme should be considered by the Contractor to facilitate waste reduction.

8.4.27 Provided that the mitigation measures are adopted, the potential environmental impacts caused by the storage, handling, transportation and disposal of general refuse are expected to be minimal, and adverse environmental impacts caused by the storage, handling, transportation and disposal of general refuse are not expected. Mitigation measures for general refuse are detailed in Section 8.5.

Land-based sediments

8.4.28 As stated in Table 8.2, sediment would be encountered from excavation works at SMA, AUT Station, NTM Station, SAT Station and SNA. Based on the interpretation of ground conditions from the available Ground Investigation (GI) information from the completed sediment sampling works during preparation of this report, the sediment quantity to be excavated due to the construction works was estimated to be approximately 64,530m³ which is based on the interpretation of ground conditions from the available Ground Investigation (GI) information from sediment sampling works during preparation of this report (details refer to Table 8.17).

8.4.29 In order to assess the land-based sediment quality, a Sediment Sampling and Testing Plan (SSTP) was submitted and subsequently approved by EPD in April 2022. In addition, a supplementary letter of “Updates to Sediment Sampling and Testing Plan” of the number of drillholes and sampling method was also submitted and approved by EPD in July 2022.

8.4.30 After the approval of SSTP, there had been changes in the boundary of works sites and works areas, as well as some locations of the VBs/EAPs/EEPs according to the latest design. Therefore, the SSTP is required to be updated and seek approval from EPD. The updated SSTP had been prepared and submitted to EPD for approval in August 2023. The updated SSTP is provided in Appendix 8.1.

8.4.31 According to the updated SSTP, a total of 47 sediment sampling locations were proposed. The timetable for the sediment sampling and laboratory testing is summarised in Table 8.9 below.

Table 8.9 Timetable for Sediment Sampling and Laboratory Testing

Task Descriptions	Time Period
Sediment sampling	June 2022 – July 2023
Tier II chemical screening	June 2022 – July 2023
Tier III biological screening	September 2022 & September 2023

8.4.32 Each sample recovered from the SI was tested in the HOKLAS accredited laboratory for the following parameters as listed in PNAP ADV-21:

(i) Metal and metalloid concentrations including chromium (Cr), copper (Cu), mercury (Hg), lead (Pb), cadmium (Cd), nickel (Ni), zinc (Zn), silver (Ag) and arsenic (As);

(ii) Concentrations of organic compounds including total polychlorinated biphenyls (PCBs) and polyaromatic hydrocarbons (PAHs); and

(iii) Concentration of Organometallics (TBT) in interstitial water.

8.4.33 After the chemical testing, the laboratory results were compared with the sediment quality criteria listed in PNAP ADV-21(Appendix A) to categorise the sediments. If the result indicated that the sediment was a Category M sediment, Tier III biological screening was then carried out to determine the appropriate disposal methods in accordance with the requirements of PNAP ADV-21:

(i) a 10-day burrowing amphipod toxicity test;

(ii) a 20-day burrowing polychaete toxicity test; and

(iii) a 48-96 hour larvae (bivalve or echinoderm) toxicity test.

8.4.34 Sediment classified as Category H with one or more contaminant levels exceeding 10 times the LCEL was also subject to the above three biological tests but in a diluted manner (dilution test).

8.4.35 Detail of sediment sampling works and testing results are discussed below.

Sediment Sampling and Testing Results

8.4.36 Chemical and biological screening of sediment samples were carried out and each sample was tested for chemical screening according to PNAP ADV-21.

8.4.37 Environmental site investigation (SI) works was carried out from June 2022 to July 2023. The SI works were conducted in accordance with the approved SSTP and were supervised by the on-site specialist. Due to the availability of site access, only 30 sediment sampling locations were completed out of 47 sediment sampling locations. The outstanding 17 sediment sampling locations would be conducted in the later stage after land resumption. The completed sediment sampling location including:

· 6 nos. at KSR (KSR-EDH(S)01, KSR-EDH(S)02, KSR-EDH(S)03, KSR-EDH(S)04, KSR-EDH(S)05 and KSR-EDH(S)06);

· 4 nos. at AUT (AUT-EDH(S)01, AUT-EDH(S)02, AUT-EDH(S)03 and AUT-EDH(S)06);

· 4 nos. at NTM (NTM-EDH(S)01, NTM-EDH(S)02, NTM-EDH(S)04 (renamed to NTM-EDH(S)20(P)) & NTM-EDH(S)05);

· 13 nos. at SAT (SAT-EDH(S)01, SAT-EDH(S)02, SAT-EDH(S)03, SAT-EDH(S)04), SAT-EDH(S)05, SAT-EDH(S)06, SAT-EDH(S)07, SATEDH(S)08, SAT-EDH(S)09, SAT-EDH(S)11, SAT-EDH(S)15, SAT-EDH(S)17 and SAT-EDH(S)18); and

· 3 nos. of SMA (SMA-EDH(S)01, SMA-EDH(S)02 and SMA-EDH(S)03).

8.4.38 A total of 10 sediment samples were collected from 6 sampling locations including NTM-EDH(S)20(P), AUT-EDH(S)01, AUT-EDH(S)02, AUT-EDH(S)03, SAT-EDH(S)04 and SMA-EDH(S)03, during SI works under supervision of on-site specialist and sent to laboratory.

8.4.39 The collected sediment sampling depths are summarised in Table 8.10. No sediment was found at the remaining sediment sampling locations.

Table 8.10 Sediment sampling depths at the sediment sampling locations

Sampling ID	Actual Coordinates		Sediment Depth		Termination Depth (mbgl) ^{(1)] (2)]}	Actual Sampling Depth to Lab (mbgl) ^{(1) (4)]}
Sampling ID	Easting	Northing	Beginning (mbgl) ⁽¹⁾	Ending (mbgl) ^(1)]	Termination Depth (mbgl) ^{(1)] (2)]}	Actual Sampling Depth to Lab (mbgl) ^{(1) (4)]}
AUT-EDH(S)01	823543	835439	3.5	4.5	5.7	3.5 – 4.5
AUT-EDH(S)02 ^(5)]	823513	835305	2.5	3.5	5.5	2.5 – 3.5
AUT-EDH(S)02 ^(5)]	823513	835305	3.5	4.5	5.5	3.5 – 4.5
AUT-EDH(S)03 ^(5)]	823505	835226	2.5	3.5	5.5	2.5 – 3.5
AUT-EDH(S)03 ^(5)]	823505	835226	3.5	4.5	5.5	3.5 – 4.5
NTM-EDH(S)20(P)⁽⁶⁾	824366	837201	5.4	5.9	8.4 ⁽³⁾	5.4 – 6.4
SAT-EDH(S)04	825626	838807	0.5	1.0	3.0	0.5 – 1.0
SMA-EDH(S)03 ⁽⁷⁾	823505	834540	2.0	3.0	5.0	2.0 – 3.0
			3.0	4.0		3.0 – 4.0
			4.0	4.5		4.0 – 4.5

Notes:

(1) mbgl = metres below ground level

(2) The depth of drillhole ending. Drilling was terminated at least 500mm below the interface between marine deposit and alluvium.

(3) The termination depth of sediment sampling works. The drillhole was transferred to geotechnical drilling afterwards.

(4) Only those samples collected and sent to laboratory for subsequent tests are presented.

(5) Including 2 nos. sediment samples “2.5m – 3.5m” and “3.5m – 4.5m”.

(6) NTM-EDH(S)04 was relocated to geotechnical drillhole and renamed to NTM-EDH(S)20(P).

(7) Including 3 nos. sediment samples “2.0m - 3.0m”, “3.0m – 4.0m” and “”4.0m – 4.5m”.

8.4.40 The collected 10 sediment samples from 6 sampling locations were tested. The testing results indicate that all the samples were below the LCEL for all contaminants, except arsenic and lead. Based on the exceedance of arsenic and lead, 2 samples were classified as Category H and 5 samples were classified as Category M. The chemical screening test results of all samples for arsenic and lead are tabulated in Table 8.11.

Table 8.11 Summary of Chemical Screening Results

Sampling ID	Sampling Depth (mbgl)	Arsenic Concentration (mg/kg dry wt) ⁽¹⁾	Lead Concentration (mg/kg dry wt.) ⁽¹⁾	Category of Sediment ⁽²⁾	Biological Testing Required (Y/N)
Lower Chemical Exceedance Level (LCEL)		12	75	-	-
Upper Chemical Exceedance Level (UCEL)		42	110	-	-
10 x (LCEL)		120	750	-	-
AUT-EDH(S)01	3.5 - 4.5	54	52	H	N
AUT-EDH(S)02	2.5 - 3.5	23	51	M	Y
AUT-EDH(S)02	3.5 - 4.5	40	35	M	Y
AUT-EDH(S)03	2.5 - 3.5	11	17	L	N
AUT-EDH(S)03	3.5 - 4.5	10	26	L	N
NTM-EDH(S)20(P)	5.4 - 6.4	11	65	L	N
SAT-EDH(S)04	0.5 - 1.0	32	371	H	N
SMA-EDH(S)03	2.0 - 3.0	13	43	M	Y
	3.0 - 4.0	16	75	M	Y
	4.0 - 4.5	14	61	M	Y

Notes:

(1) Bold indicates exceedance of LCEL. Bold and underline indicates exceedance of UCEL.

(2) Category L sediment – no exceedance of either LCEL or UCEL.

Category M sediment – exceedance of LCEL.

Category H sediment – exceedance of UCEL.

Category H sediment (>10 x LCEL) – sediment with any one or more contaminant levels exceeding 10 times of their LCEL.

8.4.41 According to PNAP ADV-21, Tier III biological screening test is not required for the sediment samples classified as Category L. For the 5 sediment samples classified as Category M as mentioned above, Tier III biological screening are required. For the 2 sediment samples classified as Category H, since 1 parameter exceeds UCEL and no parameter exceeds 10 times LCEL, Tier III biological screening test is also not required. Therefore, biological screening test is required for the 2 samples at AUT-EDH(S)02 and 3 samples at SMA-EDH(S)03. The results of the biological screening test are summarised in Table 8.12.

Table 8.12 Summary of Biological Screening Results

Sampling ID	Sampling Depth (mbgl)	Classification	Result of Biological Testing
AUT-EDH(S)02	2.5 – 3.5	Category M	Pass
AUT-EDH(S)02	3.5 – 4.5	Category M	Pass
SMA-EDH(S)03	2.0 – 4.5	Category M	Pass

8.4.42 After completion of the biological screening test, a Sediment Quality Report (SQR) would be submitted to EPD and copied to the Secretary of Marine Fill Committee (MFC) for review and comments. The SQR is provided in Appendix 8.2. The SQR provides an evaluation/ categorization of the sediment quality conditions based on the chemical screening test results and proposes disposal arrangement for the sediment to be generated for EPD’s agreement. Nevertheless, the sediment sampling and testing conducted only serve the purpose of fulfilling the EIA Study for this Project under the EIAO. Should marine disposal of sediment be unavoidable upon exhaustion of reuse options, separate submissions should be made to EPD’s Marine Dumping Control Section/ Territorial Control Office (TCO) when applying for the dumping permit under DASO. The rationale for sediment removal/ disposal would also need to be submitted to the MFC/ CEDD for agreement in accordance with PNAP ADV-21.

Sediment Disposal Options and Quantities

8.4.43 Excavated land-based marine sediment should be reused as far as possible within the Project Site before considering marine disposal. Possible methods for the reuse of land-based marine sediment on site including the reuse of land-based marine sediment as backfilling materials after mixing with cement should be explored.

8.4.44 Based on the chemical and biological screening results, the disposal options for each of the sediment samples were determined in accordance with the PNAP ADV-21 is summarised in Table 8.13.

Table 8.13 Proposed Disposal Arrangement for the Sediment to be Generated

Sample ID	Sampling Depth (mbgl)	Classification	Proposed Disposal Arrangement
AUT-EDH(S)01	2.5 – 3.5	H	Type 2 – Confined Marine Disposal
AUT-EDH(S)02	2.5 – 3.5 & 3.5 – 4.5	Mp⁽¹⁾	Type 1 – Open Sea Disposal (Dedicated Site)
AUT-EDH(S)03	2.5 – 3.5 & 3.5 – 4.5	L	Type 1 – Open Sea Disposal
NTM-EDH(S)20(P)	5.4 – 5.9	L	Type 1 – Open Sea Disposal
SAT-EDH(S)04	0.5 – 1.0	H	Type 2 – Confined Marine Disposal
SMA-EDH(S)03	2.0 – 4.5	Mp⁽¹⁾	Type 1 – Open Sea Disposal (Dedicated Site)

Note:

(1) Mp = Category M sediment passing the Tier III biological screening test

8.4.45 Based on the testing results, it is estimated that approximately 31,180m³ out of total 64,530m³ of excavated land-based sediment would be generated during construction of AUT Station, NTM Station, SAT Station and SMA Ancillary Building. The estimated quantities of sediment to be excavated is summarised in Table 8.14.

Table 8.14 Estimated Quantities of Sediment to be Excavated

Station	Sampling Location	Estimated in-situ Quantity (m³)⁽¹⁾
AUT Station	AUT-EDH(S)01	2,480
	AUT-EDH(S)02	7,460
	AUT-EDH(S)03	7,460
NTM Station	NTM-EDH(S)20(P)	470
SAT Station	SAT-EDH(S)04	3,985
SMA Ancillary Building	SMA-EDH(S)03	9,325
*Total:*		31,180

Note:

(1) The sediment quantity is estimated based on the excavation works only for current scheme of NOL. The possibility of reusing excavated sediment will be subject to the further review during detailed design and construction stages.

8.4.46 In addition, based on the available sediment testing results summarized in Table 8.11 to Table 8.13 at the time of this report preparation, the quantities for each disposal type of 31,180m³ excavated land-based sediment are presented in Table 8.15. A summary of the estimated volume of excavated land-based sediment and the proposed disposal arrangement is provided in Appendix 8.3.

Table 8.15 Estimated Quantities of Sediment under each Disposal Option

Disposal Option	Classification	Estimated in-situ Quantity⁽¹⁾ (m³)
Disposal Option	Classification	AUT Station	NTM Station	SAT Station	SMA Ancillary Building
Type 1 – Open Sea Disposal	Category L Sediment	7,460	470	-	-
Type 1 – Open Sea Disposal (Dedicated Sites)	Category M Sediment (passed the biological screening)	7,460	-	-	9,325
Type 2 – Confined Marine Disposal	Category H Sediment (does not required biological screening)	2,480	-	3,985	-
Type 3 – Special Treatment/ Disposal	Category H Sediment (failed the biological screening)	-	-	-	-
*Sub-Total*		17,400	470	3,985	9,325
*Total*		31,180

Notes:

8.4.47 The sediment would be disposed of at the designated marine disposal areas according to PNAP ADV-21. The disposal options for the excavated sediment should follow the procedures in PNAP ADV-21. The transportation routing and frequency for marine disposal to designated disposal outlets shall be agreed with EPD/CEDD during the construction phase of each stage prior to marine disposal. The recommended mitigation measures for marine disposal are discussed in Section 8.5.

Transportation Arrangement for Waste Disposal and Import of Fill Material

8.4.48 Based on the estimation of the excavated materials while assuming 25 working days per month and 9 working hours daily, the maximum number of dump trucks for transporting inert C&D materials are estimated to be about 1,039 nos. per day based on the current engineering design. A summary of the tentative transportation routings from the major works sites to the designated disposal site for inert C&D materials generated during the construction phase is shown in Table 8.16. The transportation routings may change subject to the actual traffic conditions of the roads. Nevertheless, no adverse environmental impacts are anticipated due to the transportation of waste with the implementation of appropriate mitigation measures (e.g. using water-tight containers and dump trucks equipped with mechanical cover).

Table 8.16 Tentative Transportation Routings

Construction Traffic Arrangement ⁽¹⁾
KSR(NOL) Station: KSR Station -> Kam Ho Road -> Kam Tin Road -> Castle Peak Road (Yuen Long) -> Pok Oi Interchange -> Yuen Long Highway -> Tuen Mun Road -> Wong Chu Road -> Lung Fu Road -> Lung Mun Road -> Tuen Mun Area 38 Fill Bank
AUT Station, Shui Mei Road Ancillary Building (SMA), Pok Wai Ancillary Building (PWA) and Long Ha Tsuen Ancillary Building (LHA): AUT Station -> Fung Kat Heung Road -> San Tam Road -> Castle Peak Road (Tam Mei) -> Castle Peak Road (Yuen Long) -> Pok Oi Interchange -> Shep Pat Heung Interchange -> Yuen Long Highway -> Tuen Mun Road -> Wong Chu Road -> Lung Fu Road -> Lung Mun Road -> Tuen Mun Area 38 Fill Bank
NTM Station and NTD: NTM Station + NTD -> Chuk Yau Road -> San Tam Road -> Fairview Park Interchange -> Castle Peak Road (Tam Mei) -> Castle Peak Road (Yuen Long) -> Pok Oi Interchange -> Shep Pat Heung Interchange -> Yuen Long Highways -> Tuen Mun Road -> Wong Chu Road -> Lung Fu Road -> Lung Mun Road -> Tuen Mun Area 38 Fill Bank
SAT Station, San Tin Ancillary Building (SNA) and Ka Lung Road Ancillary Building (KLA): SAT Station -> Shek Wu Wai Road -> San Tin Highway -> Yuen Long Highway -> Tuen Mun Road -> Wong Chu Road -> Lung Fu Road -> Lung Mun Road -> Tuen Mun Area 38 Fill Bank
KTU(NOL) Station, Kwu Tung Road Ancillary Building (KTA) and Pak Shek Au Ancillary Building (PAA): KTU Station -> Road L1 / Road L2 -> Castle Peak Road (Chau Tau) -> Pak Shek Au Interchange -> Kwu Tung Road -> San Tin Interchange -> San Tin Highway -> Yuen Long Highway -> Tuen Mun Road -> Wong Chu Road -> Lung Fu Road -> Lung Mun Road -> Tuen Mum Area 38 Fill Bank

Construction Traffic Arrangement ⁽¹⁾

KSR(NOL) Station:

KSR Station -> Kam Ho Road -> Kam Tin Road -> Castle Peak Road (Yuen Long) -> Pok Oi Interchange -> Yuen Long Highway -> Tuen Mun Road -> Wong Chu Road -> Lung Fu Road -> Lung Mun Road -> Tuen Mun Area 38 Fill Bank

AUT Station, Shui Mei Road Ancillary Building (SMA), Pok Wai Ancillary Building (PWA) and Long Ha Tsuen Ancillary Building (LHA):

AUT Station -> Fung Kat Heung Road -> San Tam Road -> Castle Peak Road (Tam Mei) -> Castle Peak Road (Yuen Long) -> Pok Oi Interchange -> Shep Pat Heung Interchange -> Yuen Long Highway -> Tuen Mun Road -> Wong Chu Road -> Lung Fu Road -> Lung Mun Road -> Tuen Mun Area 38 Fill Bank

NTM Station and NTD:

NTM Station + NTD -> Chuk Yau Road -> San Tam Road -> Fairview Park Interchange -> Castle Peak Road (Tam Mei) -> Castle Peak Road (Yuen Long) -> Pok Oi Interchange -> Shep Pat Heung Interchange -> Yuen Long Highways -> Tuen Mun Road -> Wong Chu Road -> Lung Fu Road -> Lung Mun Road -> Tuen Mun Area 38 Fill Bank

SAT Station, San Tin Ancillary Building (SNA) and Ka Lung Road Ancillary Building (KLA):

SAT Station -> Shek Wu Wai Road -> San Tin Highway -> Yuen Long Highway -> Tuen Mun Road -> Wong Chu Road -> Lung Fu Road -> Lung Mun Road -> Tuen Mun Area 38 Fill Bank

KTU(NOL) Station, Kwu Tung Road Ancillary Building (KTA) and Pak Shek Au Ancillary Building (PAA):

KTU Station -> Road L1 / Road L2 -> Castle Peak Road (Chau Tau) -> Pak Shek Au Interchange -> Kwu Tung Road -> San Tin Interchange -> San Tin Highway -> Yuen Long Highway -> Tuen Mun Road -> Wong Chu Road -> Lung Fu Road -> Lung Mun Road -> Tuen Mum Area 38 Fill Bank

Note:

(1) The transportation routings are indicative only and will be subject to change in future.

8.4.49 At this stage, re-use of all excavated soil materials for backfilling within the same sites is limited due to lack of stockpiling area and programme mis-match. However, parts of the excavated soil from this project can be potentially reused as backfilling materials in SAT station and NTD formation of platform subject to further review of the construction sequence, works programme and availability of the works sites/works areas for the NOL Main Line to be carried out in the next detailed design stage. At the meanwhile, the liaison for intake schedules of the potential reception sites was ongoing to explore the opportunity for reuse of C&D materials in other projects and is expected to be continued in the next design stage. Therefore, taking into account the limited availability of temporary stockpiling area on site and programme mis-match, surplus materials will be delivered to PFRF for off-site reuse while the backfilling materials will be imported. Fill materials are required from Year 2026 to 2033 (except 2032) for the construction works. Land transportation would be used to deliver the materials from Tuen Mun Area 38 Fill Bank to the Project Site.

Construction Phase Waste Summary

8.4.50 A summary of construction waste arising from the Project with total quantities of each type of construction waste to be generated, reused and disposed of as well as recommendation for outlets is presented in Table 8.17.

Table 8.17 Summary of Total Quantities for Each Type of Waste to be Generated, Respective Handling Methods and Proposed Outlets

Waste Type		Total Amount to be Generated ⁽⁶⁾⁽⁷⁾	Handling Methods/Reuse		Proposed Outlets
Inert C&D Materials ⁽¹⁾	Soft Inert Material ⁽³⁾	3,675,340 m³	· Segregation from non-inert C&D materials during stockpiling · Stockpile area (if required) should be well managed with covers and water spraying system · Reusable materials should be separated and reused as far as practicable		To be delivered to Tuen Mun Area 38 Fill Bank for off-site reuse ⁽¹⁰⁾
	Rock	431,810 m³
	AHM⁽⁴⁾	166,500 m³
Non-inert C&D Materials ⁽²⁾		125,250 m³	· Segregation from inert C&D materials during stockpiling · Reusable materials such as steel and timber should be separated and recycled as far as practicable		Designated Landfill Site to be agreed with EPD/CEDD ⁽²⁾
General Refuse		31,990 tons	· Provide on-site collection points together with recycling bins · To be collected by reputable waste collectors		To be collected by recycler/ To be delivered to NENT/WENT Landfill
Chemical Waste ⁽⁵⁾		A few hundred kilograms/ litres per month	· Store in compatible containers in designated area on site · To be collected and recycled by licensed collectors		To be collected by a licensed chemical waste collector and disposed of at a licensed chemical waste treatment and disposal facility (e.g. Chemical Waste Treatment Centre (CWTC) at Tsing Yi, or another licensed facility)
Land-based Sediment		64,530 m³ ⁽⁸⁾	Category L sediment – 17,065 m³ ⁽⁹⁾	· Reuse on site as far as possible · Type 1 – Open sea disposal at marine disposal site(s) allocated by MFC	Final disposal site to be determined by MFC
			Category M sediment (passed Tier III – biological screening test) – 16,785 m³⁽⁹⁾	· Reuse on site as far as possible · Type 1 – Open sea disposal (dedicated site) at marine disposal site(s) allocated by MFC	Final disposal site to be determined by MFC
			Category H sediment – 30,680 m³ ⁽⁹⁾	· Reuse on site as far as possible · Type 2 – Confined marine disposal at marine disposal site(s) allocated by MFC	Final disposal site to be determined by MFC

Notes:

(1) “Inert C&D Materials”, also known as public fill, includes debris, rubble, earth, concrete and TBM excavated spoil after treatment to remove the bentonite slurry which is suitable for land reclamation and site formation.

(2) “Non-inert C&D Materials” involved in the Project include top soil, vegetation, timber and steel. In contrast to public fill, non-inert C&D materials , which is not suitable for land reclamation and subject to recovery of reusable/ recyclable items (such as timber to be sent to Yard Waste Recycling Centre in Y-Park, steel to be collected by recycler), is disposed of at landfills.

(3) “Soft Inert C&D Material” mainly refers to excavated soil, etc.

(4) “AHM” includes, but not limited to, broken concrete, asphalt, bitumen, granular materials, debris, and rubble, etc.

(5) Chemical waste measured by volume (litres) includes spent hydraulic oil & waste fuel, spent lubrication oil & cleaning fluids, and spent solvent. Scrap batteries are measured by weight (kilograms).

(6) The volume is in-situ volume.

(7) The total amount has been rounded up.

(8) Based on the interpretation of ground conditions from the available Ground Investigation (GI) information from sediment sampling works during preparation of this report, the sediment quantity to be excavated due to the construction works was estimated to be approximately 64,530m³. In addition, according to the available sampling works and laboratory testing results at the time of this report preparation, approximately 31,180m³ out of total 64,530m³, have been classified and the quantity of different category of sediment are estimated. For the remaining 33,350m³ sediment, which is estimated based on the assumption of same/nearby sediment profile of outstanding sediment sampling location according to the nearby the completed sediment sampling works GI information. The proposed outlet for the remaining land-based sediment will be subject to the sediment testing results and it would be further updated once the sediment testing results available. The possibility of reusing excavated sediment will be subject to the further review during detailed design and construction stages.

(9) Based on the available laboratory testing results at the time of this report preparation, approximately 7,930m³, 16,785m³ and 6,465m³ sediment have been classified as Category L, M and H respectively. The remaining approximately 9,135m³ and 24,215m³ sediment are estimated as Category L and H respectively based on the assumption of same/nearby sediment profile of outstanding sediment sampling location according to the nearby the completed sediment sampling works GI information. The proposed outlet for the remaining land-based sediment will be subject to the sediment testing results and it would be further updated once the sediment testing results available.

(10) The disposal site of inert C&D materials is subject to the designation by the Public Fill Committee according to DEVB TC(W) No. 6/2010.

Operational Phase

8.4.51 The operation of the Project would generate the following categories of wastes:

(i) General Refuse; and

(ii) Chemical waste.

General Refuse

8.4.52 General refuse would arise from the public, station employees and commercial operators within the stations, ancillary buildings and depot. The storage and handling of these wastes may cause adverse environmental impacts. The amount of general refuse that would arise during operation phase of the Project cannot be confirmed at this stage since it would be subject to operational needs and the number of passengers, staff and any commercial operators in the future.

8.4.53 As the passengers are only transient population and will not stay in the stations, and thus the quantities of general refuse generated from passengers are negligible. Subject to operational need in the future, the estimated number of staff during operational phase is summarised in Table 8.18.

Table 8.18 Estimated Number of Staff during Operation Phase

Location	Estimated Number of Staff
Location	Non-public E&M Rooms	Concession (Retail Area)	Concession (Food & Beverage)	Non-public Operation Room	Total
KSR(NOL) Station	280	10	10	420	*720*
AUT Station	190	10	10	370	*580*
NTM Station	340	20	10	210	*580*
SAT Station	300	10	20	280	*610*
KTU(NOL) Station	200	20	-	50	*270*
Ancillary Buildings ⁽¹⁾	260	-	-	180	*440*
NTD	210	-	-	490	*700*
*Total*					*3,900*

Notes:

(1) Ancillary Buildings include EAP/EEP/VBs at Shui Mei Road, Pok Wai, Long Ha, San Tin, Ka Lung Road, Kwu Tung Road and Pak Shek Au.

(2) The total amount has been rounded up.

8.4.54 Based on Monitoring of Solid Waste in Hong Kong – Waste Statistics for 2021, a generation rate of 0.59kg/person/day for commercial & industrial waste is adopted, approximately 2,301kg of general refuse will be generated daily during the operational phase.

8.4.55 The general refuse and waste from daily operation and railway maintenance activities would include paper, wood, plastic, office waste, metal containers, scrap materials, etc. Plastics, papers and other recyclable wastes should be separated from general refuse and recycled as far as possible. The remaining refuse would be collected by waste collectors and disposed of at landfills.

Chemical Waste

8.4.56 Maintenance of the stations, ancillary buildings and depot would generate chemical waste including used cleansing materials and discarded electronic equipment. In addition, lubricants, paints, used batteries, mineral oil, coolants, and solvents would be generated during the operational phase. Adverse environmental, health and safety hazard might occur if those chemical waste are not managed properly. Considering the maximum quantity of chemical waste to be generated during the operational phase would be a few hundred litres per month, subject to future operational needs, no adverse environmental impact is anticipated with proper storage, handling, transportation and disposal of chemical waste following the requirements of the Code of Practice on the Packaging, Labelling and Storage of Chemical Waste under the provisions of the Waste Disposal (Chemical Waste) (General) Regulation. Mitigation measures for chemical wastes are detailed in Section 8.5.

8.5 Mitigation of Adverse Environmental Impacts

General

Waste Management Hierarchy

8.5.1 The waste management hierarchy has been applied in the assessment and development of mitigation measures for waste which aims at evaluating the desirability of waste management methods and includes the followings in descending preference:

· Avoidance and reduction of waste generation;

· Reuse of materials as far as practicable;

· Recovery and recycling of residual materials where possible; and

· Treatment and disposal according to relevant laws, guidelines and good practices.

8.5.2 Based on the waste management hierarchy, waste reduction measures are recommended as follow to reduce impacts and costs arisen from the Project. Recommendations of good site practices and waste reduction measures have been stated in order to achieve avoidance and minimization of waste generation in the hierarchy.

Good Site Practices

8.5.3 Adverse waste management implications are not expected, provided that good site practices are strictly implemented. The following good site practices are recommended throughout the construction activities:

· Nomination of an approved personnel, such as a site manager, to be responsible for the implementation of good site practices, arrangements for collection and effective disposal to an appropriate facility, of all wastes generated at the site;

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

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

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

· The Contractor should prepare a Waste Management Plan (WMP) as part of the Environmental Management Plan (EMP) in accordance with the ETWB TCW No. 19/2005. The WMP should be submitted to the Engineer for approval. Mitigation measures proposed in the EIA Report and the EM&A Manual should be adopted; and

· Appropriate measures to minimise windblown litter and dust during transportation of waste by either covering trucks or by transporting wastes in enclosed containers.

Waste Reduction Measures

8.5.4 Amount of waste generation can be significantly reduced through good management and control. Waste reduction is best achieved at the planning and design phase, as well as by ensuring the implementation of good site practices. The following recommendations are proposed to achieve reduction:

· Segregate and store different types of waste in different containers, skip or stockpiles to enhance reuse or recycling of materials and their proper disposal;

· Adopt proper storage and good site practices to minimise the potential for damage and/or contamination of construction materials;

· Plan the delivery and stock of construction materials carefully to minimise amount of waste generated and avoid unnecessary generation of waste;

· Sort out demolition debris and excavated materials from demolition works to recover reusable/ recyclable portions (i.e. soil, broken concrete, metal etc.);

· Provide training to workers on the importance of appropriate waste management procedures, including waste reduction, reuse and recycling; and

· Minimise over ordering and wastage through careful planning during purchasing of construction materials.

Storage, Collection and Transportation of Waste

8.5.5 Storage of waste on site may induce adverse environmental implications if not properly managed. The following recommendations should be implemented to minimise the impacts:

· Non-inert C&D materials such as top soil should be handled and stored well to ensure secure containment of the materials;

· Stockpiling area should be provided with covers and water spraying system to prevent materials from wind-blown or being washed away; and

· Different locations should be designated to stockpile each material to enhance reuse.

8.5.6 The collection and transportation of waste from works areas to respective disposal sites as well as imported fill materials from fill bank to works areas may also induce adverse environmental impacts if not properly managed. The following recommendations should be implemented to minimise the impacts:

· Remove waste in timely manner;

· Employ the trucks with cover or enclosed containers for waste transportation;

· Obtain relevant waste disposal permits from the appropriate authorities;

· Disposal of waste should be done at licensed waste disposal facilities;

· All dump trucks engaged on site for delivery of inert and non-inert C&D material from the site to the designated disposal location, including PFRFs, landfill etc., should be equipped with GPS or equivalent system for tracking and monitoring of their travel routings and parking locations by the Contractor to prohibit illegal dumping and landfilling of materials; and

· The data collected by GPS or equivalent system should be recorded properly for checking and analysis the travel routing and parking locations of dump truck engaged on site.

Construction Phase

Construction and Demolition Materials

8.5.7 Wherever practicable, C&D materials should be segregated from other wastes to avoid contamination and ensure acceptability at PFRFs areas or reclamation sites. The following mitigation measures should be implemented in handling the C&D materials:

· Carry out on-site sorting;

· Make provisions in the Contract documents to allow and promote the use of recycled aggregates where appropriate;

· Implement a trip-ticket system for each works contract in accordance with DEVB TCW No. 06/2010 to ensure that the disposal of C&D materials is properly documented and verified;

· The data collected by GPS or equivalent system should be recorded properly for checking and analysis the travel routing and parking locations of dump truck engaged on site.

On-site Sorting of C&D Materials

8.5.8 Storage of materials on site may induce adverse environmental impacts if not properly managed. Storage or stockpiling of C&D materials is not anticipated as the C&D materials generated would be removed from site immediately due to lack of space on sites; however, should any temporary storage or stockpiling of C&D materials is required, recommendations to minimise the impacts include:

· Waste, such as soil, should be handled and stored well to ensure secure containment, thus minimizing the potential of pollution;

· Maintain and clean storage areas routinely;

· Stockpiling area should be provided with covers and water spraying system to prevent materials from wind-blown or being washed away; and

· Different locations should be designated to stockpile each material to enhance reuse.

8.5.9 It is recommended that specific areas should be provided by the Contractors for sorting and to provide temporary storage areas (if required) for the sorted materials. The materials could be segregated according to the categories as shown below:

· Excavated materials suitable for reuse;

· Excavated materials for delivery to PFRFs;

· Sediments for delivery to sea disposal; and

· Non-inert C&D materials for delivery to landfills.

Re-use of C&D Materials

8.5.10 The following potential measures are identified to maximise the re-use/recycle of C&D materials generated from the Project:

· Re-use suitable material from excavation works for backfilling as far as practicable if temporary storage area availability, site condition and programme allow;

· Re-use suitable excavated rock by reworking at approved quarries (e.g. crushed as aggregates);

· Sorting of demolition debris and excavated materials from demolition works to recover reusable/recyclable portions (i.e. soil, broken concrete, metal, etc.);

· Protect recyclable material to keep it in usable condition; and

· Provide recycle bins on site to increase awareness for general refuse items such as aluminum cans, paper to facilitate segregation of waste streams and maximise recovery.

8.5.11 In order to maximise the quantity of C&D materials that can be re-used or recycled, each type of material should be carefully segregated and sorted at designated areas as far as practicable to avoid cross-contamination and to maintain the quality of the product. Arrangement with recycling contractors should be made to ensure the recyclables sorted from the waste stream are collected with reasonable care. Opportunities to use the recycled materials in other works areas of the project / other projects should also be explored.

8.5.12 Although it is desirable that C&D materials should be sorted and re-used on the same or another site, there is very limited space for temporary stockpiling on the sites in this project.

Specification of Inert C&D Materials to be Delivered Off-site

8.5.13 In case there are surplus inert C&D materials generated in the Project and are required to be delivered to the PFRFs, the inert C&D materials should fulfil the following requirements:

· Remove waste in timely manner;

· Waste collectors should only collect waste prescribed by their permit;

· Impacts during transportation, such as dust and odour, should be mitigated by the use of covered trucks or in enclosed containers;

· Reclaimed asphalt pavement should not be mixed with other materials when delivered to the PFRFs;

· Moisture content of inert C&D materials should be lowered to 25% max. when delivered to the PFRFs;

· Inert C&D materials delivered to the PFRFs should be of a size less than 250mm;

· Inert construction waste should not be in liquid form such that it can be contained and delivered by dump truck instead of tanker truck. Inert C&D materials in liquid form should be solidified before delivering to the PFRFs;

· Waste should be disposed of at licensed waste disposal facilities; and

· Maintain records of quantities of waste generated, recycled and disposed.

8.5.14 Nevertheless, the acceptance criteria of inert C&D materials to PFRFs are subject to the Fill Management Division of CEDD.

Other Mitigation Measures

8.5.15 Other mitigation measures to avoid or minimise the quantity of C&D material generated from NOL Main Line construction are described below:

· Plan carefully to ensure material is not over ordered;

· Avoid use of timber by adopting alternative material as far as practicable, e.g. steel formwork;

· Avoid use of bamboo scaffolding by adopting metal scaffolding as far as practicable;

· Plan construction activities carefully to improve the efficiency of resources;

· Design works to optimise material use and reduce C&D waste;

· Apply pre-cast elements to minimise concrete waste as far as practicable;

· Design for manufacture and assembly to reduce use of formwork/ temporary works;

· Plan and stock construction materials carefully to minimise the amount of waste generated and avoid unnecessary waste generation;

· Timber and woody materials in non-inert C&D materials should be delivered to the Yard Waste Recycling Centre in Y-Park for recycling as far as practicable prior to disposal at the designated landfill site; and

· Encourage use of re-usable/ recyclable packaging materials by suppliers.

Chemical Waste

8.5.16 For those processes which generated chemical waste, it may be possible to find alternatives to eliminate the use of chemicals, to reduce the generation quantities or to select a chemical type of less impact on environment, health and safety as far as possible. Wherever possible, opportunities for the reuse and recycling of materials will be taken.

8.5.17 If chemical wastes are produced at the construction site, the Contractor should register with EPD as chemical waste producers. Storage, handling, transportation and disposal of chemical wastes should be arranged in accordance with the Code of Practice on the Packaging, Labelling and Storage of Chemical Wastes published by the EPD. Chemical waste should be stored in appropriate containers and collected by a licensed chemical wastes collector. Chemical wastes (e.g. spent lubricant oil) should be recycled at an appropriate facility as far as possible, while the chemical waste that cannot be recycled should be disposed of at either the approved Chemical Waste Treatment Centre (CWTC) at Tsing Yi, or another licensed facility, in accordance with the Waste Disposal (Chemical Waste) (General) Regulation. A trip-ticket system should be adopted to monitor the disposal of chemical waste.

General Refuse

8.5.18 General refuse should be stored in enclosed bins separately from construction and chemical wastes. Recycling bins should also be placed to encourage recycling. Preferably enclosed and covered areas should be provided for general refuse collection and routine cleaning for these areas should also be implemented to keep areas clean. A reputable waste collector should be employed to remove general refuse on a regular basis.

8.5.19 The recyclable component of general refuse, such as aluminum cans, paper and cleansed plastic containers should be separated from other waste. Provision and collection of recycling bins for different types of recyclable waste should be set up by the Contractor. Recycling bins should be placed in prominent places to promote waste separation at-source. Arrangements should be made with the recycling companies to collect the recycle waste as required.

8.5.20 The Contractor should implement an education programme for workers relating to avoiding, reducing, reusing and recycling general waste. Participation in a local collection scheme should be considered by the Contractor to facilitate waste reduction.

Land-based sediments

8.5.21 The sediment should be excavated, handled, transported and disposed of in a manner that would minimise adverse environmental impacts. For minimization of sediment disposal, the possibility of reusing excavated sediment will be subject to the further review during detailed design and construction stages before the disposal of excavated sediment.

8.5.22 Possible methods for the reuse of land-based sediments on site including the reuse of land-based marine sediment as backfilling materials after mixing with cement should be explored. The criteria for reuse of treated sediments are proposed with reference to the Unconfined Compressive Strength (UCS) and the Universal Treatment Standards (UTS), which specify the Toxicity Characteristics Leaching Procedure (TCLP) test limits as given in Section 4.1 and Table 4.6 of the Practice Guide for Investigation and Remediation of Contaminated Land.

8.5.23 For off-site marine disposal, the requirements and procedures specified under PNAP ADV-21 should be followed. The MFC of CEDD is managing the disposal facilities in Hong Kong for the excavated sediment, while EPD is the authority of issuing marine dumping permit under the DASO.

8.5.24 For the purpose of site allocation and application of marine dumping permit and if considered necessary by EPD (Marine Dumping Section), a separate SSTP should be submitted to EPD for agreement under DASO. Additional SI works, based on the approved SSTP, should then be carried out in order to confirm the disposal arrangements of the excavated sediment. A Sediment Quality Report (SQR), reporting the chemical and biological screening results and the estimated quantities of sediment under different disposal options, should then be submitted to EPD for agreement under DASO.

8.5.25 To ensure disposal space is allocated for the Project, the Project Proponent should be responsible for obtaining agreement from MFC on the allocation of the disposal site. The contractor(s), on the other hand, should be responsible for the application of the marine dumping permit under DASO from EPD for the sediment disposal.

8.5.26 The excavated sediments is expected to be loaded onto the barge at public barging point of which the exact location will be determined by the contractor(s) and agreed by EPD/CEDD and transported to the designated disposal sites allocated by MFC. The excavated sediment would be disposed of according to its determined disposal options and PNAP ADV-21.

8.5.27 Stockpiling of excavated sediments should be avoided as far as possible. If temporary stockpiling of excavated sediments is necessary, the excavated sediment should be covered by tarpaulin and the area should be placed within earth bunds or sand bags to prevent leachate from entering the ground, nearby drains and surrounding water bodies. The stockpiles should be placed on surface completely paved or covered by linings in order to avoid contamination to underlying soil or groundwater. Separate and clearly defined areas should be provided for stockpiling of contaminated and uncontaminated materials. Leachate, if any, should be collected and discharged according to the Water Pollution Control Ordinance (WPCO).

8.5.28 In order to minimise the potential odour / dust emissions during excavation and transportation of the sediment, the excavated sediments should be wetted during excavation / material handling and should be properly covered when placed on trucks or barges. Loading of the excavated sediment to the barge should be controlled to avoid splashing and overflowing of the sediment slurry to the surrounding water.

8.5.29 In case off-site marine disposal is unavoidable, the mitigation measures to handle the excavated sediment are summarised as follows:

· All construction plants and equipment shall be designed and maintained to minimise the risk of sediments being released into the water column or deposited in the locations other than designated locations;

· All vessels should be sized so that adequate clearance is maintained between vessels and the seabed in all tide conditions, to minimise that undue turbidity is not generated by turbulence from vessel movement or propeller wash; and

· Adequate freeboard shall be maintained on barges to ensure that decks are not washed by wave action.

8.5.30 The Contractor shall monitor all vessels transporting the excavated sediments to ensure that no dumping outside the approved locations take place. The Contractor shall keep and produce logs and other records to demonstrate compliance and that journeys are consistent with designated locations and copies of such records shall be submitted to the Engineers.

· The Contractor shall comply with the conditions in the dumping permit issued under the Dumping at Sea Ordinance;

· All bottom dumping vessels (hopper barges) shall be fitted with tight fittings seals to their bottom openings to prevent leakage of materials;

· The excavated sediment shall be placed into the disposal pit by bottom dumping; and

· Discharge shall be undertaken rapidly and the hoppers shall be closed immediately. Sediments adhering to the sides of the hopper shall not be washed out of the hopper and the hopper shall remain closed until the barge returns to the disposal site.

8.5.31 If mixing of excavated sediments with cement is to be used for backfilling on-site, the following mitigation measures should be followed:

· The loading, unloading, handling, transfer or storage of bulk cement should be carried out in an enclosed system as far as practicable;

· Mixing process and other associated material handling activities should be properly scheduled to minimise potential noise impact and dust emission; and

· The mixing facilities should be sited as far apart as practicable from the nearby noise sensitive receivers and be sited under covers to minimise dust nuisance to the nearby receivers.

Operational Phase

General Refuse

8.5.32 The recyclable component of general refuse, such as aluminum cans, paper and cleansed plastic containers should be separated from other waste. Recycling of recyclable waste should be encouraged. Provision and collection of recycling bins for different types of recyclable waste should be set up by the operator. It is recommended to place clearly labelled recycling bins in prominent places which could be accessed conveniently to promote waste separation at-source. Scrap materials from railway maintenance activities should be sorted out and recovered for their resalable value as far as practicable. Routine cleaning for these areas should also be implemented to keep areas clean. General refuse should be separated from chemical waste by providing separated bins for storage to maximise the recyclable volume as far as practicable.

8.5.33 A reputable waste collector should be employed to remove municipal solid waste regularly to minimise odour, pest and litter impacts. Arrangements should be made with the recycling companies to collect the recycle waste as required. It is expected that such arrangements would minimise potential environmental impacts.

Chemical Waste

8.5.34 For those processes which generated chemical waste, it may be possible to find alternatives to eliminate the use of chemicals, to reduce the generation quantities or to select a chemical type of less impact on environment, health and safety as far as possible. Wherever possible, opportunities for the reuse and recycling of materials will be taken. Subject to operational needs, if chemical waste is to be produced, MTR Corporation should register with EPD as chemical waste producers as appropriate in accordance with the Waste Disposal (Chemical Waste) (General) Regulation.

8.5.35 The requirements given in the Code of Practice on the Packaging, Labelling and Storage of Chemical Wastes should be followed, where applicable, in handling of these chemical wastes. A trip-ticket system should be operated in accordance with the Waste Disposal (Chemical Waste) (General) Regulation to monitor all movements of chemical wastes which will be collected by a licensed collector to a licensed facility for final treatment and disposal.

8.5.36 Good quality containers compatible with the chemical wastes should be used, and incompatible chemicals should be stored separately.

8.5.37 Appropriate labels should be securely attached on each chemical waste container indicating the corresponding chemical characteristics of the chemical waste, such as explosive, flammable, oxidizing, irritant, toxic, harmful, corrosive, etc.

8.5.38 Chemical wastes (e.g. spent lubricant oil) should be collected and disposed of at appropriate facility like CWTC by licensed collectors.

8.6 Evaluation of Residual Environmental Impacts

8.6.1 With the implementation of recommended mitigation measures for the handling, transportation and disposal of the identified wastes, adverse residual waste management implications and impacts on potential hazard, air and odour emissions, noise, wastewater discharge, ecology and public transport caused by handling (including stockpiling, labelling, packaging & storage), collection, transportation and reuse/ disposal of different types of wastes are not anticipated during both the construction and operational phases.

8.7 Environmental Monitoring and Audit Requirement

Construction Phase

8.7.1 During the construction period, 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, relevant legislations and waste management guidelines.

8.7.2 Waste materials generated during construction activities, such as C&D materials, are recommended to be audited at regular intervals to ensure that proper storage, transportation and disposal practices are being implemented. This would ensure the wastes generated would be properly disposed of. The Contractor would be responsible for the implementation of any mitigation measures to minimise waste or mitigate problems arisen from waste materials.

8.7.3 A WMP should be prepared and submitted to the Engineer for approval. The recommended mitigation measures should form the basis of the WMP.

Operational Phase

8.7.4 With the implementation of good waste management practices, no adverse environmental impacts is expected to arise, and therefore waste monitoring and audit programme during the operational phase is not required.

8.8 Conclusion

Construction Phase

8.8.1 Potential waste management implications from the generation of waste during the construction phase have been evaluated. Mitigation measures follow the avoidance-minimisation-recycling-treatment-disposal hierarchy, including the opportunity for on-site sorting, reusing C&D materials etc., are devised in the construction methodology to minimise the surplus materials to be disposed. Recommendations have been made for implementation by the Contractor during the construction period to minimise waste generation and off-site disposal. With the implementation of the recommended mitigation measures detailed in Section 8.5, no adverse environment impacts would be expected.

Operational Phase

8.8.2 Potential waste management implications from the generation of waste during the operational phase have been evaluated. Recommendations have been made to ensure proper treatment and disposal of these wastes. It is anticipated that no adverse environmental impacts would arise if the mitigation measures are strictly followed.

8 waste management implications

8.1 Introduction

8.1.1 This section identifies the types of wastes that are likely to be generated during the construction and operational phases of the Project and evaluates the potential environmental impacts that may result from handling, transport and disposal of the wastes.

8.1.2 Mitigation measures and good site practices, including waste handling, storage, collection and disposal, have been recommended with reference to the applicable waste legislation and guidelines. Handling and disposal of sediments are also discussed in this section.

8.2 Environmental Legislation, Standards and Guidelines

8.2.1 The waste management implications have been assessed in accordance with the requirements outlined in Annex 7 and Annex 15 of the Technical Memorandum on Environmental Impact Assessment Process (EIAO-TM) and the EIA Study Brief (No. ESB-346/2021).

8.2.2 The relevant legislation, standards and guidelines applicable to the present study for the assessment of sediment and waste management implications include:

8.2.4 Annex 15 of the EIAO-TM describes the approaches and methodologies for assessment of waste management implications arising from the project.

8.2.11 This regulation provides control on illegal tipping of wastes on unauthorised (unlicensed) sites.

8.2.13 ETWB TCW No. 19/2005, Environmental Management on Construction Site, sets out the policy, procedures and requirements for contractor to prepare and implement an Environmental Management Plan for on-site sorting and waste reduction of C&D materials.

8.2.16 Other documents and guidelines related to waste management and disposal are summarised in Table 8.1.

8.3 Description of Environment

8.3.1 The Project covers an area from KSR(NOL) Station to KTU(NOL) Station which is predominantly rural in character. The area has a mixed urban-rural character which is predominantly occupied by low-density residential and village developments with some brownfield operations.

8.4 Identification and Evaluation of Wastes Implications

8.4.1 The assessment of waste management implications from handling, storage, collection, transportation and disposal of solid waste materials generated by the landuse proposals have been undertaken in accordance with Annexes 7 and 15 of the EIAO-TM.

8.4.2 The waste management hierarchy was applied in the assessment and development of mitigation measures for waste. The waste management hierarchy is a concept which shows the desirability of various waste management methods and comprises the following in descending order of preference:

8.4.3 All opportunities for avoiding, reducing, reusing and recycling of were explored based upon the following factors:

8.4.4 The construction activities to be carried out for the Project would generate a variety of wastes that can be divided into distinct categories based on their composition and ultimate method of disposal. The following waste types are anticipated to be generated:

8.4.5 The construction works for the Project would tentatively commence in Q2 2025. Major construction activities and the associated waste generation are summarised in Table 8.2.

8.4.6 C&D materials would be generated from excavation, demolition works, site formation, construction of facilities and station. These C&D materials comprise both inert (e.g. rocks, soil, broken concrete, building debris etc.) and non-inert components (e.g. vegetation and timber etc.).

8.4.8 Majority of the C&D materials comes from the cut-and-cover construction of stations, ancillary buildings, NTD and part of the tunnel sections. Possible measures during design development to minimise the generation of C&D materials include:

8.4.9 Summary of estimated amount of inert and non-inert C&D materials to be generated during construction phase and their estimated yearly amount are shown in Table 8.3 and Table 8.4 respectively.

8.4.11 Non-inert C&D materials generated would be reused and recycled as much as possible before disposal of at designated landfill site to be agreed with EPD/CEDD.

8.4.12 For NOL construction, earth filling activities include backfilling excavation above the stations and ancillary buildings, roadworks, site formation in northern portion of NTD to permanent formation level. General fill materials in compliance with specification will be used.

8.4.13 Earth filling activities will take place mostly between Years 2026 and 2033 based on the initial construction programme.

8.4.15 Summary of estimated amount of imported fill required for the construction works is about 509,220m3 and is summarised in Table 8.5 and Table 8.6. Nevertheless, this amount of imported filling materials should be consulted with Fill Management Division of CEDD.

8.4.16 Materials classified as chemical waste are listed in the Waste Disposal (Chemical Waste) (General) Regulation. The main chemical waste types arising from the construction of the Project may include the following:

8.4.17 Chemical waste may pose the following environmental, health and safety hazards if not stored and disposed of appropriately:

8.4.19 The estimated amount of chemical waste to be generated during construction phase is summarised in Table 8.7.

8.4.21 Mitigation measures for chemical wastes are detailed in Section 8.5. Provided that the handling, storage and disposal of chemical wastes are in accordance with these requirements, adverse environmental impacts are not expected.

8.4.22 The construction workers would generate refuse comprising of food waste, wastepaper, aluminium cans and plastic bottles during the construction period.

8.4.25 Summary of yearly estimated amount of general refuse to be generated during construction phase is summarised in Table 8.8.

8.4.31 According to the updated SSTP, a total of 47 sediment sampling locations were proposed. The timetable for the sediment sampling and laboratory testing is summarised in Table 8.9 below.

8.4.32 Each sample recovered from the SI was tested in the HOKLAS accredited laboratory for the following parameters as listed in PNAP ADV-21:

8.4.34 Sediment classified as Category H with one or more contaminant levels exceeding 10 times the LCEL was also subject to the above three biological tests but in a diluted manner (dilution test).

8.4.35 Detail of sediment sampling works and testing results are discussed below.

8.4.36 Chemical and biological screening of sediment samples were carried out and each sample was tested for chemical screening according to PNAP ADV-21.

8.4.38 A total of 10 sediment samples were collected from 6 sampling locations including NTM-EDH(S)20(P), AUT-EDH(S)01, AUT-EDH(S)02, AUT-EDH(S)03, SAT-EDH(S)04 and SMA-EDH(S)03, during SI works under supervision of on-site specialist and sent to laboratory.

8.4.39 The collected sediment sampling depths are summarised in Table 8.10. No sediment was found at the remaining sediment sampling locations.

8.4.44 Based on the chemical and biological screening results, the disposal options for each of the sediment samples were determined in accordance with the PNAP ADV-21 is summarised in Table 8.13.

8.4.50 A summary of construction waste arising from the Project with total quantities of each type of construction waste to be generated, reused and disposed of as well as recommendation for outlets is presented in Table 8.17.

8.4.51 The operation of the Project would generate the following categories of wastes:

8.4.54 Based on Monitoring of Solid Waste in Hong Kong – Waste Statistics for 2021, a generation rate of 0.59kg/person/day for commercial & industrial waste is adopted, approximately 2,301kg of general refuse will be generated daily during the operational phase.

8.5 Mitigation of Adverse Environmental Impacts

8.5.1 The waste management hierarchy has been applied in the assessment and development of mitigation measures for waste which aims at evaluating the desirability of waste management methods and includes the followings in descending preference:

8.5.3 Adverse waste management implications are not expected, provided that good site practices are strictly implemented. The following good site practices are recommended throughout the construction activities:

8.5.4 Amount of waste generation can be significantly reduced through good management and control. Waste reduction is best achieved at the planning and design phase, as well as by ensuring the implementation of good site practices. The following recommendations are proposed to achieve reduction:

8.5.5 Storage of waste on site may induce adverse environmental implications if not properly managed. The following recommendations should be implemented to minimise the impacts:

8.5.7 Wherever practicable, C&D materials should be segregated from other wastes to avoid contamination and ensure acceptability at PFRFs areas or reclamation sites. The following mitigation measures should be implemented in handling the C&D materials:

8.5.9 It is recommended that specific areas should be provided by the Contractors for sorting and to provide temporary storage areas (if required) for the sorted materials. The materials could be segregated according to the categories as shown below:

8.5.10 The following potential measures are identified to maximise the re-use/recycle of C&D materials generated from the Project:

8.5.12 Although it is desirable that C&D materials should be sorted and re-used on the same or another site, there is very limited space for temporary stockpiling on the sites in this project.

8.5.13 In case there are surplus inert C&D materials generated in the Project and are required to be delivered to the PFRFs, the inert C&D materials should fulfil the following requirements:

8.5.14 Nevertheless, the acceptance criteria of inert C&D materials to PFRFs are subject to the Fill Management Division of CEDD.

8.5.15 Other mitigation measures to avoid or minimise the quantity of C&D material generated from NOL Main Line construction are described below:

8.5.20 The Contractor should implement an education programme for workers relating to avoiding, reducing, reusing and recycling general waste. Participation in a local collection scheme should be considered by the Contractor to facilitate waste reduction.

8.5.23 For off-site marine disposal, the requirements and procedures specified under PNAP ADV-21 should be followed. The MFC of CEDD is managing the disposal facilities in Hong Kong for the excavated sediment, while EPD is the authority of issuing marine dumping permit under the DASO.

8.5.29 In case off-site marine disposal is unavoidable, the mitigation measures to handle the excavated sediment are summarised as follows:

8.5.31 If mixing of excavated sediments with cement is to be used for backfilling on-site, the following mitigation measures should be followed:

8.5.36 Good quality containers compatible with the chemical wastes should be used, and incompatible chemicals should be stored separately.

8.5.37 Appropriate labels should be securely attached on each chemical waste container indicating the corresponding chemical characteristics of the chemical waste, such as explosive, flammable, oxidizing, irritant, toxic, harmful, corrosive, etc.

8.5.38 Chemical wastes (e.g. spent lubricant oil) should be collected and disposed of at appropriate facility like CWTC by licensed collectors.

8.6 Evaluation of Residual Environmental Impacts

8.7 Environmental Monitoring and Audit Requirement

8.7.1 During the construction period, 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, relevant legislations and waste management guidelines.

8.7.3 A WMP should be prepared and submitted to the Engineer for approval. The recommended mitigation measures should form the basis of the WMP.

8.7.4 With the implementation of good waste management practices, no adverse environmental impacts is expected to arise, and therefore waste monitoring and audit programme during the operational phase is not required.

8.8 Conclusion

8.4.15 Summary of estimated amount of imported fill required for the construction works is about 509,220m³ and is summarised in Table 8.5 and Table 8.6. Nevertheless, this amount of imported filling materials should be consulted with Fill Management Division of CEDD.