Business people and tourists visiting Hong Kong for the first time will be immediately taken by the sheer scale and number of skyscrapers on display. Hong Kong has more skyscrapers than any other capital city in the world. As impressive as it is, this is not done as a tourist attraction, but rather out of necessity to house the vast population (seven million people) and business centres in a small geographic area of just 1042 km2. Country parks cover over 416km2, leaving only small tracts of suitable land for the demands of residential and commercial developments. In addition to this, Hong Kong is made up of 262 islands; hence it is easy to understand why, when a suitable piece of land becomes available to build on, one seeks to maximise the site potential. It is common to see new commercial skyscrapers soar past the 100- storey mark, with most residential towers topping out at 60 stories.
Where does this leave the Hong Kong quarry industry? Regrettably, it is not accorded a very high level of priority within government circles. With land values reaching an average of $HK5200 per square foot (in some areas up to $HK30,000 per square foot), the government is unlikely to grant mining rights on 80 hectares of land worth a minimum $HK20 billion for the sole purpose of quarrying. This line of thought required some revolutionary thinking by the government and the quarry industry to overcome the traditional ownership logic when considering the ?life cycle of a site? as opposed to the ?life cycle of a quarry?.
This article maps out the evolution of quarry operations in Hong Kong via innovative contractual mechanisms that provide the government and the community with a highly engineered site capable of further development as residential projects, community parks and marinas. This delivers the only viable option for rock extraction and processing in Hong Kong. Translated, this means that the use of the site as a quarry represents the least valuable component of the process, and indeed is a temporary and transient part of the site ‘s life cycle. In short, it is the land formation that is created as a result of the quarrying process that provides the most value.
This visionary approach provides the Hong Kong government with usable land for development that it otherwise would not have had. The case study on the Anderson Road quarry shows the end result in the form of a building platform being handed back to the government after the completion of the project works. The site is 1.3 million square metres and can potentially house more than 72,000 people in 45 50-storey residential skyscrapers valued at $HK110 billion. This is in addition to the hundreds of millions of dollars that the quarry operators have to pay the government for rights to extract the 50 million tonnes of rock. Without the site formation works the land would have otherwise been unusable for high rise construction.
In completing the life cycle of the site it effectively means a win for the quarry operator, a win for the government and, significantly, a win for the community. A rare and unusual outcome this may be, but it is likely to become more prevalent in the planning approach for future quarries to extract the full value from any potential site in high land value areas in any country. It also enables the government to use the revenue generated for other public projects in a cost-effective way.
In the quarrying world, one often encounters the ?not in my backyard? syndrome from local communities. It is envisioned that through this visionary approach quarry operators can be seen as the ?builders of community needs and dreams?, not the ?creators of community nightmares? with endless environmental consequences. As part of this article, there is an examination of how the issue of environmental protection was dealt with as quarrying contracts became more sophisticated. It also focuses on the principle that one must look to the final site use as the reason for one?s existence, not just the extraction process which is one phase (and the least valuable) of the cycle of a site. The community finds it more palatable if it knows it is getting something back before the extraction starts. Thus visualise your extraction site as a solution for potential tunnel portals, sewers/ drains, major water storage, residential and commercial building platforms, shopping centres, water sanctuaries, canal estates, marinas, parks, road cuttings, gardens, etc. Do this first and your new partners will emerge from directions previously seen as your greatest adversary.
Quarrying in the 1950s
Since the mid-1950s, the quarrying industry in Hong Kong has developed rapidly to meet the escalating demand for aggregate for large-scale housing and infrastructure projects.
Initially, the quarries were small and labour intensive. Aggregate was produced manually with hand-held hammers and primitive methods. The adverse environmental impact of quarrying was not given any due attention by the quarrying industry or the government at the time when economic development took precedence. The state of the Anderson Road quarry in the 1980s was a stark reminder to the community of how quarrying could substantially alter and deform the natural landscape, leaving behind a prominent scar visible from the north of Hong Kong.
In the late 1980s, Hong Kong experienced rapid economic growth. As the income level of its population increased, there was a corresponding increase in the awareness of environmental protection and a greater demand for a better living environment.
The government, through its legislature, enacted various legislation and regulations with a view to conserving, protecting and improving the environment. Quarrying, being an environmentally sensitive operation, fell within the ambit of these regulations. At the same time, the government introduced more comprehensive, stringent provisions in quarry contracts to greater protect the environment during and after the quarrying activities. As evidenced in the terms of the rehabilitation contracts, quarry operators are now not only contractually bound to protect the environment during the quarry operations, they must also progressively rehabilitate the affected natural landscape, with the ultimate aim of transforming the quarry sites into a landform that forms part of the surrounding habitat.
Here we will take the reader through the gradual evolution of the provisions in the quarry contracts on environmental protection since the 1960s to the present.
Quarry contracts in the 1960s
In 1964, the government granted quarrying rights at the Anderson Road quarry and the Shek O Road quarry to quarry operators Pioneer Quarries (HK) Limited and K Wah Quarry Co Limited. In 1969, the quarrying rights at Anderson Road Area No. 2 were granted to Far East Quarry Limited.
Under these quarry contracts, the operators had the rights to quarry aggregates for five years. Upon expiry of the contract period, the quarry operators were required to remove all erections on site and to leave the site clean, tidy and level. The quarry operators were not, however, required to rehabilitate the quarries during or after the quarry operations. As a result, the quarry sites were left bare and barren at the end of the contract period.
The provisions for protecting the environment during and after quarry operations were also very limited and were confined to measures that prevent noise, dust and water pollution only. These provisions included:
(i) The erection of solid screens of bamboo poles or other materials for blasting works carried out in close proximity to adjoining properties.
(ii) The provision of dust suppression and dust extraction plant and equipment, and the carrying out of precautions to prevent dust nuisance resulting from quarry operations.
(iii) The carrying out of precautions to secure the efficient protection of all streams, waterways and bathing beaches against pollution which may cause injury to fish, plant life or discolouration of the sea.
These were the only provisions for the protection of the environment. The situation did not improve significantly in the next decade, which is discussed below.
Quarry contracts in the 1970s
Compared to the quarry contracts in the 1960s, the quarry contracts in the 1970s were slightly more detailed as far as environmental protection was concerned.
All the quarry contracts in the 1970s, namely the contract for the Cha Kwo Ling combined area in 1972, the Anderson Road Area No. 3 in 1973 and the Lamma quarry in 1977, included provisions on landscaping in addition to the requirements on dust suppression and streams and waterways protection contained in the 1960s contracts.
Most of the provisions on landscaping required the quarry contractors to:
(i) Finish the rock face to a safe slope as extraction of stone was completed from each bench of the quarry face.
(ii) Construct retaining walls, drains, etc for the healthy growth of turf, trees and shrubs.
(iii) Level and grade the quarry floor and top soil and turf the area to the satisfaction of the government?s engineer.
(iv) Trim rock faces to a stable slope, remove loose boulders, trim earth faces to a stable slope and protect these slopes by planting shrubs, turf, etc.
There were also provisions requiring the quarry operators to keep the quarry sites clean and tidy and to arrange for regular removal of all refuse, garbage and waste materials from the sites to an authorised place of disposal.
Quarry contracts in the 1980s
In the 1980s, quarry industries worldwide started to pay due regard to the adverse environmental impact of quarrying activities and devise means to minimise damage to the environment by their operations. The Hong Kong government also imposed more stringent obligations on quarry operators.
The quarry contracts in 1981 for Lam Tei quarry and Shek O quarry contained detailed provisions for dust control, noise control, water pollution control, cleanliness of site, effect of blasting, rock crushing plant, earthworks, surface of protection of soil slope, disposal of overburden and construction of all channels.
In 1989, the government prepared the Metroplan Landscape Strategy for the Urban Fringe and Coastal Areas (MLS). The objective of MLS was ?to provide a comprehensive framework for landscape conservation and enhancement of the metropolitan urban fringe and coastal areas?.
The MLS identified the Anderson Road quarry as an area of degraded landscape requiring rehabilitation. The government?s Development Progress Committee (now known as the Committee on Planning and Land Development) carried out extensive public consultation on the development of the rehabilitation scheme. These efforts coincided with the increased awareness in environmental protection of the quarrying industry worldwide.
Balancing community and commercial interests
A viable rehabilitation scheme must balance two sets of interests, namely, those of the community who desire a cleaner environment and those of the quarry operators seeking to maximise profits by lowering operation costs and increasing production capacity.
Bearing in mind that the cost of the rehabilitation project represents a significant financial expense in the accounts of the quarry operators, it is essential to develop a comprehensive strategy to support viable quarry operations with built-in progressive and co-ordinated rehabilitation schemes. With the publication of the MLS, the government imposed contractual obligations on the quarry operators to rehabilitate the quarry sites.
Quarry contracts in the 1990s
In the 1990s, Hong Kong property prices hit rocket-high levels. The construction industry?s demand for aggregate exceeded 20 million tonnes per year. At the same time, the community was less tolerant of deteriorations in their living environment and expected measures to reduce pollution generated by the construction industry. This created great public pressure on both the government and quarry operators of environmentally sensitive operations to minimise the adverse environmental impacts caused by the quarrying activities.
The quarrying industry was well tuned to society?s attitudes towards environmental protection and prepared to implement measures to conserve and protect the environment. As a result, various rehabilitation contracts were signed between the quarry operators and the government. Under these contracts, quarry operators were required to rehabilitate the quarries within a specified period, in return for the rights to process and sell rock reserves excavated during the course of the rehabilitation. The rehabilitation works generally involved re-contouring and extensive planting to blend the quarries into the surrounding natural habitat.
Ecology
Restoration was planned to be undertaken progressively, managed through a Landscape Management Group composed of the quarry company, industry-related consultants, and government representatives managing the contact and as the end user.
The quarry operator involved consultants such as botanists, ecologists and landscape architects to prepare their landscape and rehabilitation plans in order to optimise the greening performance and coverage of the engineered slopes.
The key success factors underlying optimal performance in the rehabilitation contracts include the following attributes:
? Sustainable economic model – allowing for the quarry companies to foster reasonable profits whilst undertaking the rehabilitation and final land formation works.
? Long-term tenure – to give ownership of the final outcome to the operator, to enable the investment costs in the plant and equipment to be absorbed, and allow time for establishment and continual improvements over the project duration.
? Consistency of tenure – to ensure ownership and consistency in the final outcome.
? Stakeholder participation and communication – to ensure all stakeholders were involved in the long-term project, allowing feedback, opportunity to change and improved performance, and to promote the final vision and intent of the project.
? A balanced multi-disciplinary integrated professional team – to ensure that the final outcome considered all stakeholders? objections.
? Agreed Landscape Master Plan – the final plan should provide a framework for tracking progress and focusing on the end use vision.
? Innovation for restoration – to ensure that best global practices were adapted in the works and that the performance of the works were communicated and key features incorporated into future projects and contracts.
Hong Kong rehabilitation contracts
The Hong Kong quarry rehabilitation contracts were primarily a quarry development site with an overlaying final slope formation plan agreed in advance with the government, ensuring that the site is restored to a form that best merges in with the surrounding environment and end-use plan.
The quarry companies were responsible for the design and construction of the slope formation, drainage and final rehabilitation of the site.
In return, the government granted the quarry companies the rights to extract the reserve and produce and sell aggregate from the site, to set-up and operate concrete, asphalt and block plants on site, and to establish and operate an emulsion facility for a period specified within the contract.
The associated downstream products of the rock extracted (eg aggregates, concrete, asphalt and blocks) are designed to assist in providing a sustainable economic model for the contract, related to the overall site works.
Since the scheme was adopted, the government has let five rehabilitation contracts:
1. 1988 Turret Hill quarry (25ha)
2. 1995 Lamma quarry (49ha)
3. 1993 Shek O quarry (45ha)
4. 1996 Anderson Road (KWP) quarry (86ha)
5. 2006 Lam Tei quarry (30ha)
Rehabilitated landform
The final landform of a quarry rehabilitation contract has to be designed and constructed to create the maximum benefit for the end use of the site, whilst taking into consideration slope safety. The rehabilitation plan should aim to blend in with the adjoining natural environment, whilst satisfying all other multi-disciplines.
Quarry case studies
Case Study I – Shek O quarry – Hong Kong Island
The Shek O quarry was developed by Alliance Construction Materials Limited, a joint venture with Hanson PLC which has been recently taken over by Heidelberg and Cheung Kong Infrastructure Ltd. The site, located on Hong Kong Island, has been in operation since 1964, and provides a valuable rock resource for the rapid development of the high rise city of Hong Kong.
Shek O quarry is situated at the western tip of D?Aguilar Peninsula at the south eastern edge of Hong Kong Island in Tai Tam Bay, adjacent to the Tai Tam Country Park.
The operator of the Shek O quarry has conducted, on its own initiative, a study on the quarry development and developed a scheme for the final landform. This study not only provided recommendations on the final landform but contained measures to harmonise the quarry with the surrounding natural landscape.
The scheme for the final landform – the ?Shek O Marina? – envisaged the formation of a protected harbour surrounded by low-rise housing or recreational facilities. This scheme encompassed two main proposals. The first involved the diverting of Shek O Road, which would then allow extension of the quarry area to the north-easterly direction. The second was to flatten the prominent quarry slope along the north-eastern boundary to a shallow angle, so that elevated platforms could be created for optional low-rise development.
In October 1987, copies of a conceptual study, Shek O Marina, were circulated within the government. This study expressed some reservations about the continued operation of the quarry. The interest generated by the study, however, prompted the operator to commission the building of models in 1988 to show the proposed ?Marina? landform. A rehabilitation contract was subsequently signed in 1994.
The quarry operator is required to carry out the following works under the rehabilitation contract:
(i) Construct a new Shek O Road to eliminate the hairpin bend of the old Shek O Road and shorten the road by 600m.
(ii) Create a new landform which will blend into the natural landscape of Cape D?Aguilar Peninsula.
(iii) Provide nesting sites for peregrine falcons on the southern boundary cliffs.
(iv) Plant the slopes with exotic and native trees to establish a natural self-sustaining eco-system and create suitable habitats for birds, mammals and insects.
In 1993, the government established a rehabilitation contract to improve the land formation and restoration of the site. The contract period was for 10 years with a further two-year management obligation, providing enough for the quarry company to extract the rock, undertake the slope development works; construct the drainage system and roads, undertake a major road realignment of Shek O Road, and to ensure adequate time for the establishment of the planted areas of woodland, scrubland and amenity landscaping.
The quarry predominantly supplies aggregate to the Hong Kong Island market using 2000- to 3000-tonne barges loaded directly from the final product stockpiles. The barge logistics employed at the site virtually eliminates all road transport impact on the community from the quarry which would otherwise account for more than 220,000 truck movements per year.
The objective of this rehabilitation works was to create a habitat which can evolve into the kind of advanced ecological community found on the adjacent native slopes, with similar flora and fauna.
Slope development and landscape restoration
In the rehabilitation and slope design phase, the developed slopes need to blend into the natural surroundings. This needs to be achieved working with granite rock benches and the impediment of the harsh coastal environment.
In order to achieve the best result, it was decided that the existing quarry boundary should be expanded to reduce the overall slope angle of the site, providing a final profile that was more conducive to plant vegetation growth.
To achieve this, it was necessary to, firstly, extend the land area and, secondly, to realign the only road leading to Shek O. This realignment provided the community with reduced travel time and improved safety, as it removed a severe hairpin bend.
Quarry scope of works
In the plan of works, the quarry operator was required to relocate and realign the road that serviced the Shek O residence, to construct all of the slopes, to vegetate the slopes with the landscape design matrix, to construct the drainage channels and natural water courses to transfer the runoff to the ocean, to construct all permanent roads and car parks for the end use, and to construct a marine cove as a prominent feature for the recreation users.
In exchange for these works, the quarry operator was permitted to extract the rock and sell the products into the market.
Community benefits
During the project term, the site was used as a temporary casting basin for the casting of the tube sections for the Western Harbour Tunnel, one of Hong Kong?s three harbour tunnel crossing structures.
Given the coastal access to the site, it was also used as a rock receptor facility, receiving the surplus rock generated from the major projects in Hong Kong.
The key benefit to the community was that the surplus waste rock generated from these Hong Kong projects was converted into a valuable resource again for use in Hong Kong through the production of concrete and asphalt products, produced from aggregates derived from the surplus rock products.
This system provided the most efficient method of recycling products on an extremely large scale, reducing the impact on Hong Kong?s limited land fill sites.
Landscape Master Plan
The Landscape Master Plan was an agreed plan designed by the consultants in association with the suite of multi- disciplined experts. It contained a section-by-section detail of the hydro-seeding mix and planting methodology, the soil type and depth, the plant species in the form of mix matrices showing the density and orientation of planting, different matrices for different aspects, details of fertiliser and watering requirements.
? An ecological survey of the area was undertaken to:
? Provide protection from fires.
? Create a buffer zone.
? Facilitate the application of nesting sites in the cliff features to encourage peregrine falcons nesting.
? Ensure geotechnical stability of all areas.
Several trial slopes were undertaken to determine the optimum design and technique focused on the vegetation growth height and rate, the fatality count, and the coverage performance.
The land formation features of the Shek O quarry include the marine cove, the cliff features with peregrine nesting areas, and the natural water courses discharging into the Marine Cove. The gradual benches provide a scenic winding road access to the final car park where the site is intended for recreational use.
Vegetation
The design of the final slopes was selected at 35 degrees which meant that only hardy species were likely to survive in the exposed coastal environment. A balanced mix of rapid growing nurse species was chosen to provide early shade and shelter for slower growing natural indigenous species. After trials were undertaken, a woodland mix was selected for the site planting.
To enhance the natural outlook, several designed stream courses were cut into the slopes linked in with the site drainage to provide an additional feature and varied ecosystem on the site.
The vegetation classification on the slopes was a mix of grass and low shrubs, shrubland with groups of trees, a woodland mix, salt-tolerant species and fast-growing ornamental planting.
The rock face – scree slope formation
Scree slope formation was selected for the Shek O quarry. This was determined after a study of the planting trial performed in 1991 on the site, in agreement with the quarry company.
Detailed cross-sections of the scree slopes were established and continually reviewed based on the final achieved performance.
Outline of scree slope development stages
? The soil mantle comprised of shot rock material with a geo-textile fabric overlay that prevented the scree surface from dispersal. The rock surface of the scree slope was prepared so that there were no loose rocks or cavities.
? A compacted soil mantle of 600mm thickness was applied to the geo-textile layer, providing sufficient depth and anchorage for the plants.
? An erosion mat was used as the final layer in combination with hydro-seeding, producing grass cover only. No trees and shrubs were used in the hydro-seeding.
? Plants were watered thoroughly before being inserted into soil-drenched pits on the slope surface. The ongoing survival rate of the plant highly depended on the supply of sufficient water, adequate sunlight and the protection from encroachment from weeds and grasses. Watering was to be applied in moderation to encourage deep root growth and was designed to taper off over a two-year period.
Tracking performance
The non-native species tended to be more prolific than the natives with tree planting at 1.5m spacing, of a height of 150 to 600mm. The site design mixes were varied according to habitat, with classifications being shaded slopes, that is, slopes in full sun and streamside slopes.
Firebreaks were created using fire-resistant belts of vegetation. These were planted using 100 per cent evergreen trees, planted in 20m wide belts of acacia confusa.
Case study II – KWP Quarry – Anderson Road, Kowloon
Anderson Road quarry
The Anderson Road quarry is a site developed by KWP Quarry Ltd, a joint venture between Alliance Construction Materials Limited and K Wah Quarry Ltd.
The Anderson Road quarry is located in the east of the Kowloon Peninsula. The site has been used for granite excavation for more than 45 years. The excavation extends over 1.5km long and over 200m high.
The Anderson Road quarry features prominently in south-east Kowloon and is highly visible from various directions. Quarry operations at the Anderson Road quarry have resulted in a visible scar from many parts of Hong Kong, including the Victoria Harbour, Kowloon and the north of Hong Kong Island which many people regard as one of the most beautiful settings for a city anywhere in the world.
In 1993, an environmental impact assessment (EIA) was carried out on the operation of the Anderson Road quarry. The EIA identified several environmental impacts created during quarrying and site formation operations, in particular, blasting and solid waste impacts. However, the EIA concluded that, with the implementation of suitable mitigation measures and a good monitoring and audit program, such adverse impacts could be controlled and brought within the established standards and guidelines.
In 1997, the government awarded a contract for the rehabilitation of the Anderson Road quarry together with quarrying rights for 15 years to KWP Quarry Company Ltd. The rehabilitation mainly focuses on maintaining a viable ongoing quarry operation whilst at the same time restoring the landscape for future housing development. Under this contract, the quarry operator is required to form a new landform consisting of seven benches of rock slopes at the central portion (overall height about 200m), three benches separated by 20m high rock slopes on the east and west ends and a platform of 40 hectares.
The quarry operator is also required to provide a green cover, consisting of trees and shrubs, to the final landform to blend in with the natural environment.
These are to be achieved through detailed contractual provisions on the environmental protection benchmarks, the landscaping and site cleanliness requirements, which are set out as follows:
(i) On the environmental front, the relevant contractual requirements include:
? Preparing and submitting proposals for the control, monitoring and auditing of all relevant environmental issues, including issues on air quality, noise, water quality and waste disposal, to the satisfaction of the Director of Environmental Protection within 210 days from the date of commencement of the rehabilitation work.
? Complying with all recommendations contained in the proposals for the control, monitoring and auditing of all relevant environmental issues and observing all ordinances, by-laws, regulations and rules governing the control of any form of pollution, including air, noise, water and waste pollution, and implementation of all pollution control, audit and mitigation measures contained in the above-mentioned proposals to the satisfaction of the Director of Environmental Protection.
? Making application for and obtaining all necessary licences and permits from the Director of Environmental Protection for the execution of the rehabilitation work.
(ii) As to landscaping requirements, the quarry operator is required to adopt the following landscaping strategies:
? As a general goal, progressively produce a natural-looking, vegetated and stable final landform that blends in with the surrounding landscape.
? Devise and implement both long-term and short-term strategies. In the long term, provide a vegetated quarry face consisting primarily of native or semi-native plant species wherever practicable. In the short term, the priority is to establish a green cover to the soil surface and rock slopes as quickly as possible.
? The scheme for restoring the quarry is required to be divided into two parts: (a) rehabilitated slope (comprising three component parts, namely, cliff feature, rock slopes steeper than 35 degrees to the horizontal and slopes shallower than 35 degrees to the horizontal), and (b) rehabilitated platform (comprising the landform area for future development).
It is fair to say that the Anderson Road quarry is one of the most talked about quarries in Hong Kong, given its prominent but less than appealing appearance. In June 1998, an article titled ?Bite into Mountain at Tai Sheung Tok? appeared in the South China Morning Post, which commented on the barrenness of the quarry site. The so-called ?bite area? referred to in the article is, in fact, an area marked for rehabilitation in the rehabilitation contract.
The first phase of the rehabilitation process was completed in early 2000. The remaining phases are scheduled to be completed in 2013. Hopefully, after the completion of the rehabilitation works, the scar in south-east Kowloon will disappear.
Rehabilitation plan
The government contract brought two quarry companies together to form KWP Quarry Company Ltd to reinstate the quarries and to progressively restore the landscape and then hand back the site to the government for their end use.
The quarry includes the feature of three large drop cuts of sizes up to 60m in depth, providing the following benefits:
1. Increased rock reserve.
2. Creation of a water storage facility to service the concrete plant and crushing plant.
3. Increased volume to allow overburden dumping.
Landscape profiles
Various landscape cross-sections are provided to cater for the varying slope and aspects of the site.
Relevant Legislation
Apart from imposing more comprehensive and stringent contractual obligations on quarry operators, the government also enacted the following legislation to monitor the quarrying industry:
1. Waste Disposal Ordinance (Cap. 354)
The Waste Disposal Ordinance was enacted in 1980. I