2 PROJECT DESCRIPTION

· Sub-Area 1 is located at the northernmost part of PDA, it extended up to the edge of woodland adjacent to the Fanling Raw Water Pumping Station. This piece of land is generally regular and is adjacent to high density housing development such as Cheung Lung Wai Estate;

· Sub-Area 2 is bounded by the above-mentioned woodland, which is extended up to the existing access road of On Po in the south side. There is a man-made pond in this Sub-Area to provide water source for wildlife.

· Sub-Area 3 is bounded by the existing access road of On Po in the north and the narrow edge adjacent to Tai Lung Experimental Farm at the south. This piece of land is irregular in shape and there are a number of tree clusters at the sides and in the middle of the Sub-Area; and

· Sub-Area 4 is located at the southernmost part of PDA. It is bounded by the boundary of Sub-Area 3 to the Site boundary of PDA.

2.3 Predicted Future Without the Proposed Development

Existing Condition

2.3.1 Currently, PDA is a part of the FGC Site with around 32 ha and is bounded by Ping Kong Road to its northeast; Po Kin Road to its north; Fan Kam Road to its northwest and west; rural settlements of Ping Kong to its east; Tai Lung Experimental Farm and a green hillock to its southeastern and southern ends.

2.3.2 PDA is mainly woodland and grassland with a mixture of common native species, self-seeded species and ornamental species used for slope planting. Besides, various wetland habitats including ponds, marsh and swampy woodland were found within PDA. The northern of PDA is regular in shape and there are houses, carpark and ball courts within the area. The central and southern part of PDA is more irregular in shape. The swampy woodland identified in the southern part of the PDA (i.e. Sub-Area 4) supporting some plant species of conservation importance e.g. Chinese Swamp Cypress (Glyptostrobus pensilis) and Ardisia villosa.

2.3.3 There is no recognized sites of conservation importance within PDA. Only a Fung Shui Wood (Lin Tong Mei Fung Shui Wood) is located to the southwest of the PDA. The distance between the Fung Shui Wood boundary and PDA is approximately 300m.

Predicted Future Conditions without Project

2.3.4 Population in Hong Kong is increasing and there is an urgent demand to have strategic sites for housing development. Without the Project, alternative housing sites may need to be identified to ease the pressing demand on public housing, which generally refers to other undeveloped land. In order to accommodate the increasing population and household growth effectively in short to medium terms, it would be more effective to develop this land.

2.3.5 In the absence of this Project, the conditions of most habitats are expected to remain largely unchanged and the woodland and fairway trees are predicted to be maintained in PDA. Area with high ecological value such as the swampy woodland and marsh, etc. could also be maintained.

Predicted Future Conditions with this Project

2.3.6 This Project was putting forward to provide approximately 12,000 public housing units, accommodating a total population of approximately 33,600. Social welfare facilities (e.g. neighbourhoold elderly centre, child care centre etc.), educational facilities, local retail etc. will be proposed for supporting the proposed developments.

2.3.7 From urban planning perspective, development of PDA, especially the northern part which is in close proximity of Fanling / Sheung Shui Town Centre, could create a natural extension of the town area. Development of this area not only make use of the well-developed public infrastructures in the vicinity, but also bring social and economic benefits to the local community and the general public.

2.4 Development and Environmental Opportunities

2.4.1 The development and environmental opportunities are summarized as follows:-

Development and Environmental Opportunities

2.4.2 Existing footpaths and cycling track in vicinity of PDA, particularly along Po Kin Road and Pak Wo Road, provide convenient pedestrian connection between the PDA and the major public transport facilities such as MTR Sheung Shui Station.

2.4.3 The northern part of PDA (i.e. Sub-Area 1) is within 15-minute walk to existing Fanling / Sheung Shui Town Centre and MTR Sheung Shui Station. And it is immediately adjacent to existing and planned residential areas such as Cheung Lung Wai Estate. The development at this part could serve as a natural extension of the town and has the potential of becoming the most vibrant part of PDA in the future.

2.4.4 PDA is served by various modes of public transport services in vicinity. The key modes of public transports are franchised bus services, green minibus services and rail services. With the comprehensive coverage of public transport services nearby, PDA is considered to have good accessibility via public transport.

2.4.5 Results of the traffic impact assessment revealed that the traffic capacity of key roads / junctions in vicinity of PDA is limited after the implementation of recently planned road improvement works. The development scale of PDA has been optimized with minor road improvement works in local road including Ping Kong Road and Po Kin Road to avoid overloading the junctions.

2.4.6 Flora and fauna species of conservation importance such as Glyptostrobus pensilis, Aquilaria sinensis, Masked Palm Civet and Red Muntjac were recorded within PDA. Based on the selected Development Option, the associated impact to the environment have been assessed in this EIA report in accordance with the Study Brief issued by the Authority on 9 July 2019. In terms of ecological value, Sub-Area 1 is relatively lower (i.e. low to medium) compared to Sub-Area 2 (i.e. medium), Sub-Area 3 (i.e. medium) and Sub-Area 4 (i.e. medium to high).

Housing Type, Public and Private

2.4.7 It is proposed that public housing will be the dominant in the future development because Public housing is in strong demand and hence support from the community will be greater.

2.4.8 The detailed splitting of public housing (public rental or subsidized housing) will be determined later to reflect the demand prevailing. There is no difference between the environmental impact for such subdivision of public housing. The infrastructure will be schemed to allow both arrangements to be possibly achieved.

Flat Production and Population

2.4.9 Apart from environmental aspects, we have conducted a traffic study and other technical assessments to confine the extent of existing development to be about 12,000 public housing flats with a household assumption of 2.8 persons per flat, that is approximate population of 33,600 to ensure adequate capacity from the existing road and transport network to serve the future population.

2.5 Public Consultation

2.5.1 District Council and Town Planning Board will be consulted for endorsement of the proposed development and zoning amendment according to Town Planning Ordinance. Comments received from District Council and Town Planning Board will be reviewed and addressed accordingly. Details of The proposed development would be further optimized in consideration of comments from public and different stakeholder.

2.5.2 Project Profile No. PP-583/2019 was released to the public for comments in May 2019. Public offered their views during the 14 days public inspection period of the Project Profile. Subsequently, upon formulating various development options, a meeting was held with Green Groups on 25 September 2020. The key comments received from the public are summarized in Table 2.1.

Table 2.1 Key Comments Received from Public and Green Group

Aspects	Key Comments	Responses
Traffic Infrastructural Support	Commenters showed their concerns about additional loading to roads and transport infrastructure due to the project; and suggested to assess based on avoiding the risk of affecting the swamp and hydrology which would be caused by widening Fan Kam Road.	A comprehensive Traffic Impact Assessment has been conducted under this Study to ensure that there is no insurmountable impact to the existing transport infrastructure. With consideration to the Public’s concern, the major access to the proposed development is provided at Ping Kong Road so as to minimize the traffic impact to Fan Kam Road.
Community and Transportation Facilities	Commenters were generally concerned about the insufficiency of the G/IC and transportation facilities in coping with the existing and future population under FGC development.	While formulating the development options, advice has been sought from relevant departments such as Social Welfare Department to ensure that the facilities provided are sufficient to serve the additional population under FGC development.
Air Quality and Noise Nuisance	There were concerns about air and noise pollution in the surrounding areas during construction phase and operation phase.	The air quality and noise impacts during the construction and operation phases of the Project have been assessed quantitatively in the EIA. The mitigation measures for air quality including watering once per hour on active works areas, exposed areas and haul roads are proposed for dust suppression. Other site management measures such as, good site practices, and environmental monitoring and audit (EM&A) programme are recommended. Air quality impact from vehicular emission associated with the Project and the existing and planned road network, and industrial emissions in the vicinity of the Project during operation phase has been assessed. The results concluded that the predicted cumulative air quality impacts at all air sensitive receivers (ASRs) would comply with the Air Quality Objectives (AQOs). Therefore, no adverse air quality impact during operation phase is anticipated. Regarding the construction noise, the construction noise associated with the use of powered mechanical equipment (PME) for different stages of construction has been assessed. With the implementation of practical mitigation measures including good site management practices, use of Quality Powered Mechanical Equipment (QPME), use of movable noise barrier, noise enclosure and noise insulating fabric and provision of minimum separations from the affected educational institutions or avoidance of any noisy construction activities during the school examination period, the predicted construction noise impact would comply with the criteria stipulated in the EIAO-TM. Hence, no adverse impact arising from the construction of the Project would be anticipated. During the operation phase, at source direct mitigation measures, including the application of low noise road surfacing material have been proposed to mitigate the noise impacts to the sensitive receivers such as Cheung Lung Wai Estate, HKCKLA Buddhist Wisdom Primary School, Tung Wah Group of Hospitals Ma Kam Chan Memorial Primary School, Elegantia College. With the implementation of proposed mitigation measures as discussed in Section 3 and Section 4 4 of the EIA report, no adverse air quality and noise impact is anticipated during construction and operation phases.
Water Quality and Hydrology	Commenters showed their concerns about the changes and cumulative impacts to the water flow and water quality due to the proposed development, including diversions of streams and underground water. Some suggested taking cautions on surface runoff during the construction and operation phase. In addition, there are small watercourse connected to the nearby AFCD Tai Lung Experimental Farm and should be examined and determine the impact.	Diversion of watercourses will only be occurred in Sub-Area 1. Impacts to water flow and water quality due to the proposed development are not anticipated. Besides, as there are no deep tunnel under this Project, the change of groundwater table is therefore not anticipated. During construction phase, proper site management measures should be implemented to control site runoff and drainage, and thereby prevent high sediment loadings from reaching downstream sections of the river/stream. Suitable facility such as portable chemical toilets, will be provided for the workforce on-site. The key potential source of impact on water quality during the operation phase of the Project would include the road run-off, sewage and wastewater effluents and storm run-off from building. Mitigation measures with adequate maintenance are recommended to remove grits and grease from the runoff during operation. In addition, all sewage and wastewater generated from these facilities would be properly collected and diverted to public sewer. Only landscaping works are proposed near the AFCD Tai Lung Experimental Farm, impact to the nearby watercourse is therefore not anticipated.
Sewerage	Commenters showed their concerns about whether the development could accommodate the increased sewerage due to increased population.	In view of the public concerns, the development layout and parameters have been optimised to ensure that no insurmountable impact will be posed by the development.
Landscape and Visual	Commenters showed their concerns about the trees, especially on OVT (Old Valuable Tree) and they shall be valued and assessed with complex ecological and biodiversity values under Development Bureau handbook on Tree Management. .	According to database of Old and Valuable Tree (OVT) provided by LCSD and our site tree survey, there is currently no registered OVTs found within the study area (Sub-Areas 1 to 4). However, a detailed tree survey has been conducted in Sub-Area 1 to identify the potential Old and Valuable Trees that may be affected. Mitigation measures such as retaining the Potential OVTs in-situ and transplantation are proposed in our development. Besides, landscape resources and characters within the study area have been identified and evaluated in the Landscape and Visual Impact Assessment. Assessment of landscape resources is based on the criteria of distinctiveness, maturity and quality of the landscape resources. The importance of each resource has been evaluated in the Landscape and Visual Impact Assessment.
Cultural Heritage	Commenters showed their concern on the historic/heritage value and cultural significance of FGC and golfing in Hong Kong, also with its reactional function. Those were suggested to be assessed per international standards. Moreover, some commenters showed their concerns about the historical and social significance of ancestral graves in FGC and suggested to provide linkage and points of reference between identification on culture and tradition. Furthermore, some comments that FGC has wide significant impact in terms of historical, social and cultural significance.	A Cultural Heritage Impact Assessments is conducted with reference to the Antiquities and Monuments Ordinance (Cap.49) and Guidelines for Cultural Heritage Impacts Assessment (CHIA) issued by AMO and follow where appropriate, paragraph 4.3.1(c), item 2 of Annex 10, items 2.6 to 2.9 of Annex 19 and other relevant parts of the EIAO-TM on EIA Process, S.16. Assessments are undertaken by heritage experts with local expertise and / or qualified archaeologists if archaeology is involved. Fanling Golf Course, The Hong Kong Golf Club is a New Item proposed for grading assessment by Antiquities Advisory Board (AAB). The cultural heritage impact assessment concludes the impact of the proposed works on the New Item is undetermined pending grading assessment. Mitigation measures will be recommended to minimize the impact arising from the proposed development to the New Item. 4 graded historic buildings and 1 new item, 11 not-graded historic buildings and 17 of Clan graves have been identified within the CHIA study area. 1 ancestral grave was identified in Sub-Area 1. The ancestral graves within the potential development areas were taken into considerations while selecting the development options. In the latest proposed development layout the ancestral graves are mostly preserved and the impact to those graves was kept minimal.
Ecology - general	Ecology at Sub-Area 2 serves as a habitat for the faunas species of conservation importance. Therefore, massive development at Sub-Area 2 should be avoided.	Only recreational and ancillary facilities with minimal new structure/change to existing site conditions are proposed in Sub-Area 2 & Sub-Area 3 so as to prevent the damages to the habitat of fauna species. Considering the ecology at Sub-Area 1 is of relatively lower ecological value, only Sub-Area 1 is proposed for housing development.
		Sub-Area 4 will be preserved the most in order not to disturb the habitat of the species of conservation importance Glyptostrobus pensilis. Sub-Area 3 will also be preserved and served as a buffer area to conserve Sub-Area 4.
Ecology - flora	The commenters recognized that the ecology, particularly the group of critically endangered Glyptostrobus pensilis (Chinese Swamp Cypress, which are exotic to Hong Kong) in the swampy woodland, at Sub-Area 4 (i.e. the most southern portion of the site) is of high conservation value and should be preserved. Besides, there were concerns about Ardisia villosa, which is also a rare species. Those species contain large historical values and significant to FGC. Their special conservation importance documented by scientific studies raised commenters concern and consider the ecological impact to those flora species. Commenters also concern about the combination of tree species within the area.	Due to the rarity and conservation importance of Chinese Swamp Cypress, the development has been avoided affecting this species directly and indirectly. The housing development will be around 1km from the woodland of Chinese Swamp Cypress (Swampy Wodoland). While Ardisia villosa was recorded near the housing development, but the woodland where Ardisia villosa located will be preserved and no direct impact to this species is expected. Should Ardisia villosa is found within the development area during the detailed design stage, transplantation to a suitable location may be proposed.
Ecology - fauna	Concerns were raised on Malayan Night Heron and other fauna species including bats and insects which are with strong connection within FGC wetlands. Commenters suggested to carry out comprehensive avifauna surveys and thoughtful ecological surveys.	Comprehensive avifauna and other fauna surveys were conducted for period over 12 months covering both wet and dry seasons. Due to the ecological importance of wetland habitats within the Project Site (i.e. swampy woodland, marsh, pond), all of these important habitats are proposed to be preserved in the adopted development option. Potential impacts to the species rely on wetland habitats are considered insignificant.

2.6 Formulation of Development Options

2.6.1 In light of capitalizing on the strategic location and local character, three development options were proposed and considered:-

(1) For Development Option 1, housing development with high density and low density scattered in Sub-Area 1, Sub-Area 2 and Sub-Area 3 respectively.

(2) For Development Option 2, public housing development is proposed in Sub-Area 1 of PDA only. Sub-Areas 2 to 4 are proposed to be preserved with minimal works Sub-Areas 2 to 3 and no works in Sub-Area 4.

(3) For Development Option 3, PDA is fully developed with housing development in all four Sub-Areas. This option targets on maximizing housing provisions to meet the pressing housing needs.

2.7 Examination of Development Options

2.7.1 The main access routes to/from the FGC Site and urban area would be mainly via the Ping Kong Road, Po Kin Road, Fan Kam Road and Tai Tau Leng Roundabout to Fanling Highway. All vehicular ingress/egress points in this Sub-Area must only be allowed on the future improved Ping Kong Road as the existing traffic conditions and capacity of Fan Kam Road are very limited.

2.7.2 The operational performance of key junctions in the vicinity of the FGC Site has been assessed. To support new residential development at the FGC, junction improvements are required at Tai Tau Leng Roundabout, junction of Castle Peak Road – Kwu Tung/Fan Kam Road, junction of Fan Kam Road/Po Kin Road and junction of Po Kin Road/Ping Kong Road. With such improvements, the highest attainable flat yield of the FGC Site acceptable in traffic terms ranges from 11,000 to 13,000 public housing units, the major constraint being Tai Tau Leng Roundabout (even with improvement).

2.7.3 Having considered various factors, Development Option 2 is selected for assessment. The development size on Sub-Area 1 can provide 12,000 public housing units, which is sufficient to accommodate the above flat yield of 11,000 to 13,000 public housing units. Its associated environmental impacts have been considered and assessed in this EIA report.

2.7.4 Under Development Option 2, Sub-Area 1 is recommended for residential development. This Sub-Area comprises of three parcel of land uses, namely a special school site (of about 8,500m² in land area) at its northern tip; a retention of a small hillock to the north of Ming Tak Court (known as Pei Tau Ling Kok) to its south-eastern end; and the rest of its (of about 80,000m² in land area) is planned for a high-rise, high-density public housing development with a maximum domestic plot ratio of 6.5. It is anticipated that upon completion of this development this public housing site will yield a total of about 12,000 flats to meet the soaring housing demand in the community.

2.7.5 Three west-east airpath/visual corridors (i.e. one with 30m wide in the south, one with 15m wide in the middle and one with 15m in the north) and one north-south airpath/visual corridor (i.e. 15m in the middle of the site) are provided to enhance the local wind and visual permeability. A public transport interchange (“PTI”) should be taken into account and be located near Ping Kong Road for the benefit of all users. All welfare facilities will be accommodated inside the podium and/or above the PTI.

2.7.6 The maximum building height in the notional layout should be ranged from the tallest point at 164 mPD in the middle descending outwards to the 127 mPD.

2.7.7 Under Development Option 2, Sub-Area 2 to Sub-Area 4 is recommended for recreation cum conservation use which is expected to be a passive natural area. Only recreational and ancillary facilities with minimal new structure/change to existing site conditions would be provided in Sub-Area 2 to 3. No works would be carried out in Sub-Area 4. Details of such arrangements could be provided in later stage.

2.8 Recommended Development Parameters and Land Use in Sub-Area 1

2.8.1 To the northeast and further north of PDA are the urbanized areas of Sheung Shui New Town where high-rise and high-density residential developments are commonly found. Examples including Cheung Lung Wai Estate and Ching Ho Estate. With respective of planning context, the local character and the existing development intensities in the surroundings, a PR of 6.5 was proposed at Sub-Area 1.

2.8.2 Based on the chosen development option, the development layout is developed and presented in Figure 2.2. The proposed public housing development is at the northern part of PDA (i.e. Sub-Area 1) with an approximate net site area of 80,000 m². The Site is estimated to provide a maximum of 12,000 flats, accommodating a population of approx. 33,600. Alongside with a number of social welfare facilities, kindergartens, a special school and community hall are proposed to serve the population. Meanwhile, local retail and other non-domestic facilities will also be provided within the Site. The latest development parameters for the Site are summarized in Table 2.3 as follows:-

Table 2.3 Summary of Development Parameters

Public Housing Development at Sub-Area 1
Net Site Area (m²) (about)	80,000
Domestic Plot Ratio	6.5
Domestic Gross Floor Area (m²) (about)	520,000
Average Flat Size (m²)	43 (TBC)
Maximum Flat Production (about)	12,000 (TBC)
Average Household Size	2.8
Estimated Design Population	33,600
Number of Domestic Blocks	12
Preliminary Building Heights in mPD and No. of Storeys (subject to fine adjustment in next stage of the project)	127mPD to 164mPD 37 to 43 storeys (TBC)
Non-Domestic Plot Ratio	0.5
Proposed Non-Domestic GFA (m²) (about)	40,000
Local Retail (GFA) (m²)(about)	10,000
Other Non-Domestic Facilities (GFA) (m²)(about)	26,540
Kindergarten (GFA) (m²)(about)	2,200
Community Hall (GFA) (m²)(about)	1,260
Social Welfare Facilities (Exempted from GFA) (m²) (about)	18,100
Reserved Area of Provision of Social Welfare Facilities (Exempted from GFA) (m²) (about)	7,900
Public Car Park (Nos. of Parking Space) (Exempted from GFA)	300
Public Transport Interchange (Exempted from GFA)	1
Earliest Target Completion	2029
School Site
Site area (m²) (about)	8,500

2.9 Land Use in Sub-Area 2 to 4

2.9.1 With due consideration to preserving the diverse habitats found within Sub-Area 2 to Sub-Area 4, land uses such as Other Specific Uses have been considered. Recreational and ancillary facilities with minimal new structure/change to existing site conditions to support the recreation activity will primarily be provided in Sub-Area 2 . Landscaping works including but not limited to planting and transplanting works that are compatible with existing habitats are also anticipated within the Sub-Areas 2 to 3. For Sub-Area 4, no works is anticipated in order to preserve its ecology. Subject to further investigation, the actual land use will be further confirmed and a proper management plan with management approach including establishment of conservation area will also be formulated to preserve the existing valuable habits.

2.9.2 Uses in Column 1 and Column 2 of “Other Specified Uses” annotated “Recreation cum Conservation” are listed as follows:

Column 1 (Uses always permitted)

Field Study/Education/Visitor Centre

Golf Course

Nature Reserve

Nature Trail

Park and Garden

Picnic Area

Playground/Playing Field

Column 2 (Uses that may be permitted with or without conditions on application to the Town Planning Board)

Eating Place

Government Use

Holiday Camp

Place of Entertainment

Place of Recreation, Sports or Culture

Public Utility Installation

Public Vehicle Park (excluding container vehicle)

Shop and Services

2.10 Key Infrastructure

2.10.1 In order to support the future development and population inside PDA, the following infrastructures are proposed:-

(1) Site formation works;

(2) Building works (i.e. foundation works and superstructure);

(3) Slope works and other geotechnical works;

(4) Roadworks;

(5) Waterworks;

(6) Sewerage works;

(7) Drainage works;

(8) Landscaping works;

(9) Public Transport Interchange (PTI); and

(10) Other infrastructure works including laying of utilities, etc.

2.10.2 Minor road modification works is proposed to be carried out at Ping Kong Road, northeast of the PDA.

2.10.3 Associated supporting infrastructure and utilities outside the Project boundary, which are considered as part of the Project, including (i) laying of sewer to Shek Wu Hui Sewage Treatment Works; (ii) junction improvements; (iii) laying of drainage; and (iv) laying of fresh watermains and flushing watermains. Impacts associated with these activities will be assessed in terms of cumulative impact in this EIA study.

2.11 Proposed Construction Methodologies and Alternatives

Site Formation Works

2.11.1 Site formation works will be carried out by cutting or filling the existing ground profile to form platforms for future housing development. Surplus of inert C&D material generated during the site formation works would be reused on site or provided to other concurrent construction projects as far as practicable. The remaining inert C&D material will be disposed of at the public fill reception facilities. To allow more flexibility on the development layout, the latest site formation proposal would mainly involve cut slope. Use of retaining wall is also worth considering subject to further study in next stage of this project.

2.11.2 In view of the level difference between formation level of Southern Edge of Sub-Area 1(from +16.0mPD to +19.5mPD) and about +20.6mPD in the Northern Edge of Sub-Area 2, retaining structure may be required at the southern side of the proposed housing development to overcome the level difference. The use of various retaining structures such as L-shaped reinforced concrete (RC) retaining wall and piled retaining wall have been considered. Cut slope has also been considered due to cost-effectiveness. A comparison of the benefits and dis-benefits between L-shaped retaining wall, piled retaining wall and cut slope is illustrated in Table 2.4 below.

Table 2.4 Comparison of Benefits and Disbenefits between Different Construction Methods for Retaining Structures in the Housing Site

L-shaped Retaining Wall

Piled Retaining Wall

Cut Slope

Landscape Impact

Higher

Substantial temporary works is required during construction and only minor landscape mitigation measures (i.e. vertical greening) could be adopted

Less

Minimal temporary works is required during construction and only minor landscape mitigation measures (i.e. vertical greening) could be adopted

Less

Substantial temporary works is required during construction but major landscape mitigation measures such as hydro-seeding can be adopted to improve the landscape and visual

Construction Duration

Longer

Substantial excavation and substantial temporary works are required. Long construction period is anticipated.

Shorter

Without the substantial excavation works and minor temporary works, shorter construction period is anticipated.

Medium

Without substantial excavation works and with substantial temporary works, the construction duration is anticipated to be between L-shape retaining wall and pile retaining wall.

Construction Noise

Less

General excavation would induce minimal construction noise

Higher

Piling would induce intensive construction noise

Less

General excavation would induce minimal construction noise

2.11.3 General measures for reduction of waste generation, on-site or off-site re-use and recycling have been evaluated. Section 7.4 under Chapter 7 will discussed this issue in detailed.

Treatment of Contaminated Soil

2.11.4 Site investigation activities to obtain soil and/or groundwater sample by drilling rigs and laboratory testing will be carried out after the site is accessible and prior to construction to confirm the extent and degree of the contamination at the site. Remediation methodologies such as solidification/stabilization and/or biopiling will be adopted in accordance with the Practice Guide for Investigation and Remediation of Contaminated Land (published by EPD), if contamination is identified. The treated soil will be re-used as backfilling materials within the site subject to appropriate disposal criteria. Off-site disposal will be served as the last resort.

Road Works and Utilities

2.11.5 The proposed road works include minor road modification of Ping Kong Road and road junction improvement. Major utilities works also involve construction of new drainage pipes , laying of sewer and laying of watermains to support the development. The construction works will involve trenchless method such as mini-tunnel boring machine (TBM) and pipe jacking or at-grade road construction, earthworks, temporary supports erection, utilities laying, concreting, laying of sub-base materials and laying of bituminous or concrete surfacing layers.

2.11.6 In general, the cut-and-cover method is deployed for constructing underground utilities. It is a proven and commonly used method of excavation and subject to the ground condition and design of the infrastructures, it is in general cost-effective. A significant engineering advantage of this method over other methods is that it can accommodate variations in ground conditions, the alignment, and non-uniform utilities structures.

2.11.7 For the underground utilities passing through roundabout and railways, trenchless method may be adopted to avoid disruption to the busy road traffic. With the trenchless method, construction of an open trench along the utilities alignment is not necessary and the directly affected areas are limited to the launching and reception shaft only. Thus, direct impacts to adjacent areas associated with the excavation and backfilling works are anticipated to be reduced.

Public Transportation Interchange (PTI)

2.11.8 Covered Public transportation Interchange (PTI) will be constructed in Sub-Area 1. A social welfare facilities building is proposed above the PTI.

Landscaping Works in Sub-Areas 1 to 3

2.11.9 Minor landscaping works such as planting and minor transplanting works will be carried out. Proper tree protection will be provided for trees to be retained in-situ and areas in close proximity to the construction site. Tree monitoring shall be conducted throughout the construction period to ensure continued tree health for all retained trees.

Building Structures

2.11.10 The public housing development, PTI and social welfare facilities building will be constructed by the Housing Department (HD) and the school will be constructed by the Architectural Services Department (ArchSD). It is envisaged that the foundation works will involve piling machineries. For the superstructure, erection of precast concrete elements and in-situ concreting work are envisaged.

2.11.11 Two piling options have been discussed during the preliminary design, including (a) large diameter bored piles and (b) driven H-piles.

2.11.12 (a) For large diameter bored pile, it is a common piling method in Hong Kong for housing projects. Shafts of the large diameter bored piles are constructed by traditional boring machines with temporary steel casings as a supporting system. Chisel and grab system with casings, and Reverse Circulation Drilling (RCD) are the common large bored pile construction plants. Typical sizes of large diameter bored piles range from 1m to 3m in diameter.

2.11.13 Pros and Cons for the large diameter bored pile are listed summarized below:

Pros

Cons

· Large structural capacity

· Generate relatively less noise and vibration during pile installation

· Relatively easy to overcome underground obstructions

· Higher flexibility in designing longer piles to suit design requirements

· Risk of loosening of surrounding soil, causing ground movement and structural impacts on the adjacent structures; and

· Larger working space is required

2.11.14 (b) Driven steel H-piles, the piling installation method is relatively simple and less settlement is anticipated due to loss of soil. This construction method is to pitch H-piles using percussion method until final sets are achieved. A hydraulic hammer is commonly used for pile driving in Hong Kong.

2.11.15 Pros and Cons for the Driven Steel H-pile are listed summarized below:

Pros

Cons

· Pile installation method is relatively simple and degree of redundancy can be easily incorporated to provide flexibility to deal with any unexpected ground condition; and

· Pile type can be designed to withstand high bending and tensile stresses.

· Generate relatively high noise and vibration, which may be sensitive to nearby sensitive receivers; and

· Longer construction period is anticipated;

· Highly affected by unforeseeable ground condition

2.11.16 By comparing the above two options, bored piles are generally preferable in view of the following:

· Relatively less noise and vibration impacts;

· Relatively shorter construction period; and

· Satisfying the loading and ground condition requirements.

Sewage Treatment Works/ Sewage Pumping Stations

2.11.17 A thorough assessment has been made to the sewerage implication and the results are presented in Section 6 – Sewerage and Sewage Treatment Implication. Based on the current design scheme and assessment results, construction works of Sewage Treatment Works and Sewage Pumping Stations are not anticipated under this Project.

2.12 Implementation Programme

2.12.1 The implementation programme is summarized in Table 2.5 below. It is anticipated that the commencement and completion of the proposed development in Sub-Area 1 will be in Year 2024 and Year 2029.

Table 2.5 Summary of Tentative Implementation Programme

Stage	Works Components	Time Line
Stage 1	Public Housing Development in Sub-Area 1 · Site clearance and site formation works · Construction of internal Road · Pipe works and utilities works · Construction and building works of public housing site · Construction of public transport interchange (PTI) and bus terminus	2024 - 2029
Stage 2	School Site Development in Sub-Area 1 · Site clearance and site formation works · Construction of internal Road · Pipe works and utilities works · Construction of special school	2024 - 2028
Stage 3	Associated Road Works outside PDA · Junction improvement works at Po Kin Road / Ping Kong Road · Minor road improvement works at Ping Kong Road	2024 - 2029
Stage 4	Associated Infrastructure Works outside PDA · Pipe works and utilities works	2024 - 2029
Stage 5	Recreational cum Conservation Area in Sub-Areas 2 to 4	To be further reviewed

2.2.6 In order to more specifically address the irregular-shaped site, PDA is delineated as Sub-Area 1 to Sub-Area 4. The boundary of each Sub-Area is shown in Figure 2.1and the Sub-Areas are described as follows:-

2.3.3 There is no recognized sites of conservation importance within PDA. Only a Fung Shui Wood (Lin Tong Mei Fung Shui Wood) is located to the southwest of the PDA. The distance between the Fung Shui Wood boundary and PDA is approximately 300m.

2.3.5 In the absence of this Project, the conditions of most habitats are expected to remain largely unchanged and the woodland and fairway trees are predicted to be maintained in PDA. Area with high ecological value such as the swampy woodland and marsh, etc. could also be maintained.

2.4.1 The development and environmental opportunities are summarized as follows:-

2.4.2 Existing footpaths and cycling track in vicinity of PDA, particularly along Po Kin Road and Pak Wo Road, provide convenient pedestrian connection between the PDA and the major public transport facilities such as MTR Sheung Shui Station.

2.4.7 It is proposed that public housing will be the dominant in the future development because Public housing is in strong demand and hence support from the community will be greater.

2.6.1 In light of capitalizing on the strategic location and local character, three development options were proposed and considered:-

2.7.6 The maximum building height in the notional layout should be ranged from the tallest point at 164 mPD in the middle descending outwards to the 127 mPD.

2.8 Recommended Development Parameters and Land Use in Sub-Area 1

Table 2.3 Summary of Development Parameters

2.9 Land Use in Sub-Area 2 to 4

2.10 Key Infrastructure

2.10.1 In order to support the future development and population inside PDA, the following infrastructures are proposed:-

2.10.2 Minor road modification works is proposed to be carried out at Ping Kong Road, northeast of the PDA.

Site Formation Works

Treatment of Contaminated Soil

Road Works and Utilities

Public Transportation Interchange (PTI)

2.11.8 Covered Public transportation Interchange (PTI) will be constructed in Sub-Area 1. A social welfare facilities building is proposed above the PTI.

Landscaping Works in Sub-Areas 1 to 3

Building Structures

2.11.11 Two piling options have been discussed during the preliminary design, including (a) large diameter bored piles and (b) driven H-piles.

2.11.13 Pros and Cons for the large diameter bored pile are listed summarized below:

2.11.15 Pros and Cons for the Driven Steel H-pile are listed summarized below:

2.11.16 By comparing the above two options, bored piles are generally preferable in view of the following:

· Relatively less noise and vibration impacts;

· Relatively shorter construction period; and

· Satisfying the loading and ground condition requirements.

Sewage Treatment Works/ Sewage Pumping Stations

2.12.1 The implementation programme is summarized in Table 2.5 below. It is anticipated that the commencement and completion of the proposed development in Sub-Area 1 will be in Year 2024 and Year 2029.

Table 2.5 Summary of Tentative Implementation Programme