Provisional Legislative Council
Panel on Environmental Affairs
Panel on Health Services



The Administration's preferred method of handling the disposal of clinical waste, animal carcasses and other special wastes was by means of a centralised incineration facility (CIF). The feasibility study for the CIF Project was completed in 1995 and we submitted our proposal to the Public Works Sub-committee (PWSC) for funding approval. However, it became clear to the Administration at the meeting of the PWSC on 17 May 1995 that Members would not give their support to the funding of the CIF project, and the PWSC paper was withdrawn.

2.This paper advises Members about developments concerning the treatment facilities for clinical waste and animal carcass disposal and our proposed control strategy for clinical waste.


3.Following the withdrawal of the PWSC paper, we have been exploring combinations of the following options to deal with clinical waste and animal carcasses:

Clinical Waste Disposal

    --utilising the existing incinerator at the Chemical Waste Treatment Centre (CWTC)

    --retrofitting1 the incinerators at the Pamela Youde Nethersole Eastern Hospital (PYNEH)

    --retrofitting1 all the Hospital Authority's (HA's) pathological waste incinerators


Animal Carcasses Disposal

    -- building a stand-alone animal carcass cremator

    -- incorporating a by-product plant at the proposed Sheung Shui Slaughterhouse (SSSH)

    -- landfilling

4.During our review on the Centralised Incineration Facility (CIF) project, we have explored five combinations of the above options and compared them with the CIF option. The five combinations explored are:

  1. utilising the incinerator at the Chemical Waste Treatment Centre (CWTC) to treat clinical waste and building a stand-alone animal cremator to treat animal carcasses;

  2. utilising the CWTC incinerator to treat clinical waste, upgrading the incinerators at the PYNEH for clinical waste treatment and backup, and building a stand-alone animal cremator to treat animal carcasses;

  3. utilising the CWTC incinerator to treat clinical waste, incorporating a by-product plant at the SSSH to deal with animal carcasses and condemned meat, and building a small stand-alone animal cremator to handle animal carcasses;

  4. retrofitting HA's existing pathological waste incinerators to treat clinical waste and building a stand-alone animal cremator to treat animal carcasses; and

  5. disposing of clinical waste and animal carcasses at landfills.

The Centralised Incineration Facility Option

5.From a waste management operational point of view, none of the five combinations of options could match the CIF option. The CIF would provide a comprehensive solution for the disposal of clinical waste, animal carcasses and other special wastes in an environmentally satisfactory manner. The CIF would utilise state-of-the-art technology, and as it would be purpose built, the plant could allow for future expansion in capacity. The CIF option would also offer greater reliability because there will be back-up facilities on site to handle clinical waste during plant failure/maintenance. However, the CIF option requires a large capital investment ($290 million), a relatively large piece of land (1.5 hectares), and the site identified, in Tuen Mun, was strongly opposed by the local residents. The relatively remote location was also a contributor to the higher cost of collection and transportation of clinical waste.

Combination A: CWTC and Stand-alone Animal Cremator

(a) CWTC

6.The CWTC was commissioned in 1993 to deal with the Hong Kong's chemical waste and is equipped with a high-temperature incinerator. Whilst the performance of the CWTC incinerator is well proven for chemical waste treatment, its technical feasibility of incinerating clinical waste was uncertain because the design requirements for chemical waste and clinical waste are different. In particular, the emission standards for clinical waste are more stringent than those for chemical waste. To verify the performance of the CWTC incinerator, we conducted a trial burn of clinical waste at the CWTC in November 1996.

7.The results of the trial burn indicate that it is technically feasible to incinerate clinical waste at the CWTC. The stack emissions complied with the emission standards for pathological waste incinerators except for mercury, which marginally exceeded the requirements. The problem of mercury can be overcome by implementing improved segregation of mercury-containing waste from clinical waste and utilising the carbon injection technique in the flue gas scrubbing process to reduce any mercury remaining in the stack gas.

8. The existing rotary kiln incinerator and the associated system at the CWTC would have to be modified to accept clinical waste. The capacity of clinical waste that could be accepted with the modification is 15 tonnes per day. The system would be designed to meet the standards imposed by the Air Pollution Control Ordinance (APCO) and could handle clinical waste at least up to the year 2008. However, no backup facility and cold store are provided. The forecast date for completing the permanent modifications at the CWTC to accept clinical waste will be early 2000, but we will examine the possibility of advancing the starting date by using some interim arrangements.

(b) Stand-alone Animal Cremator

9. A new stand-alone animal cremator would be built to handle 12 tonnes of animal carcasses per day. The animal cremator would be designed to meet the standards imposed by the APCO. A cold store would be provided. The proposed site for the animal cremator is a portion of the CIF site that was previously identified in Tuen Mun. We forecast that this facility could be commissioned by 1999, if no delays occur.

(c) Overall Comments

10.One advantage of this option is the early timing of having the proper disposal facilities for clinical waste and animal carcasses in place. Another advantage is that the stand-alone animal cremator requires a smaller site than the CIF, so part of the land reserved for the CIF can be freed for other purposes. The operational standards and the stack emission quality of the CWTC incinerator would comply with the requirements of the APCO. The clinical waste treatment capacity is limited theoretically by the chemical waste intake at the CWTC, although this is unlikely in practice because the chemical waste intake is decreasing. One disadvantage of this option is that there is no standby incinerator available and landfill disposal is required during plant shut down. To cope with this problem during plant shut down, we intend to send human body parts, tissues, and excised organs which are generated from surgical operations to the proposed stand-alone animal cremator for disposal. The rest of the clinical waste will be delivered to the landfills for disposal.

11.As EIAs have been conducted for the CWTC (for chemical waste treatment) and the CIF in the past, supplementary EIAs would be conducted to address the treatment of clinical waste at the CWTC and the treatment of animal carcasses at the animal cremator.

(d) Cost Implications2

12.The total capital cost of this option is estimated at $151 million ($51 million for the modifications to the CWTC and $100 million for the construction of the animal cremator).

Note 2: All cost figures presented in the paper are at December 1996 prices.

Combination B: CWTC, Stand-alone Animal Cremator and Upgrading PYNEH Incinerators

(a) CWTC and Animal Cremator

13.The features are the same as those listed for CWTC and the Animal Cremator in Combination A.

(b) Upgrading the Pathological Waste Incinerators at PYNEH

14.The existing pathological waste incinerators at the PYNEH would be upgraded by adding an air scrubbing system. However, as the PYNEH incinerators are not designed as a centralised facility for the disposal of clinical waste, the upgrading work would involve significant building alterations and modifications because the incinerators are located at the core building of PYNEH. Due to site constraint, the conversion work would not provide a satisfactory arrangement in the handling and storage of the waste from other hospitals. Also, major disruption would be caused to the operation of PYNEH.

(c) Overall Comments

15.The advantages and disadvantages of this combination are similar to that of Combination A. One additional advantage of this combination is the availability of an additional outlet for clinical waste disposal where the PYNEH incinerators can act as standby incinerators. However, as the PYNEH incinerators could not be satisfactorily converted into a centralised facility, its use to treat the clinical waste from PYNEH only would not be cost effective.

(d) Cost Implications

16.The total capital cost for this combination is $208 million ($51 million for the modifications to the CWTC, $100 million for the construction of the animal cremator, and $57 million for the modifications to the PYNEH incinerators).

Combination C: CWTC, By-product Plant and Small Stand-alone Animal Cremator

(a) CWTC

17.The features are the same as those listed for the CWTC in Combination A.

(b) By-product Plant

18.The by-product plant would be located at the Sheung Shui Slaughter House (SSSH) and would treat animal carcasses. The plant would require the application of extreme mitigation techniques for air quality and odour control and 5 chimneys each of at least 40 metres high to prevent air pollution and odour nuisance.

(c) Small Stand-alone Animal Cremator

19.A new stand-alone animal cremator of a size smaller than that in Combination A would be built to handle animal carcasses, condemned meat and offal that require incineration. The animal cremator would be designed to meet the standards imposed by the APCO and a cold store would be provided.

(d) Overall Comments

20. The advantages and disadvantages of this combination are similar to that of Combination A. One additional advantage of this combination is that there would be meat and bone meal by-products being generated from the by-product plant for sale and this is an additional outlet for animal carcasses. However, the market for selling meat and bone meal is limited and the by-products may end up being disposed of as waste at the landfills. In addition, there are contractual problems if we add a by-product plant to the SSSH because the building contract for the SSSH has already been awarded and construction has begun. Any alteration at this stage would inevitably cause delay in the completion of the SSSH. Also, there may be "fung shui" objections from local residents to the construction of the by-product plant. Lengthy public consultation will be required.

(e) Cost Implications

21.The total capital cost for this combination is around $250 million.

Combination D: Retrofitting HA's Existing Incinerators and Stand-alone Animal Cremator

(a) Retrofitting HA's Existing Incinerators

22.HA's existing pathological waste incinerators would be retrofitted to meet the best practicable means of controlling air pollution as required under the APCO.

(b) Stand-alone Animal Cremator

23.The features are the same as those listed for the animal cremator in Combination A.

(c) Overall Comments

24. One advantage of this combination is that the pathological waste incinerators are located near the source of much of the clinical waste, thus the transportation times and collection costs for clinical waste would be lower. However, as all the existing pathological waste incinerators are sub-standard, it would be an expensive exercise. In addition, retrofitting is either not feasible or not cost effective for the 10 remaining incinerators in service in HA due to plant conditions, limited residual life span of the equipment and site constraints. Moreover, not all old hospitals are equipped with incinerators and the newly planned hospitals do not have incinerators (having been designed when the CIF was assumed), thus some HA incinerators may have to act as regional incinerators for other hospitals. As HA's existing incinerators are not designed as regional incinerators to receive waste from other HA's hospitals, the acceptance of clinical waste from other hospitals would cause disruption to the hospitals' operation. This option leaves the clinical waste generated from sources other than the HA unaddressed.

(d) Cost Implications

25.The total capital cost for this combination is over $311 million because the capital cost required for retrofitting HA's existing pathological waste incinerators is over $211 million.

Combination E: Landfilling

(a) Landfilling

26. Clinical waste and animal carcasses would be disposed of in trenches at the three existing strategic landfills.

(b) Overall Comments

27.The advantage of this combination is that there is no need to develop any new treatment facility, thus there is no additional capital cost. However, from an environmental, hygiene and aesthetic standpoint, landfilling is not a satisfactory method for treating and disposing of clinical waste generated from surgical operations (e.g. body parts, human tissues, excised organs) and animal carcasses. There is a need to maintain certain incineration facilities to treat such wastes similar to the existing arrangements even if the landfill option were to be adopted. Landfilling is not a complete solution to the clinical waste disposal problem.

(c) Cost Implications

28.There is no additional capital cost because no new treatment facility would be developed.


29.Whilst we have not done detailed estimates of the recurrent costs of the various options, it is evident that the more facilities to be operated the greater the recurrent costs will be.


30. From the above analysis, Combination A (utilising the CWTC incinerator to treat clinical waste and building a stand-alone animal cremator to treat animal carcasses) is the most viable and economically attractive alternative to the CIF option. As such, we propose to utilise the CWTC for incinerating clinical waste and to build a stand-alone Animal Cremator for treating animal carcasses, subject to further environmental and financial assessments.


31.Clinical waste are potentially infectious and bio-hazardous and need to be disposed of in an environmentally sound way. Even for clinical wastes of relatively low risk, they may be aesthetically offensive by nature and require careful treatment as part of the overall waste management strategy. Clinical waste disposal needs to be subject to control, not only because of the inherent risks they pose, but also because of legitimate public concerns, and the occupational safety of waste collectors and waste disposal staff, who may come into contact with these wastes.

32.The handling of clinical waste is currently not subject to any legislative control. Although it is recognised that clinical waste should be segregated from other municipal waste and handled separately, there is no uniform practice adopted by the medical profession. Existing practice notes and guidelines issued by the medical bodies are voluntary in nature. The HA has drawn up a code of practice on the management of clinical waste in 1993 and this code is uniformly implemented in all public hospitals. At present, due to the lack of proper incineration facilities, most clinical waste generated in Hong Kong is disposed of at landfills. Although the Environmental Protection Department has implemented a permit system to administratively control clinical waste disposal at landfills, its effectiveness is limited as some clinical wastes are mixed with domestic waste and are disposed of without applying for a permit. Therefore, there is a need to provide a proper control framework for clinical waste disposal.

33.We intend to introduce legislative control on clinical waste disposal by way of a regulation to be made under the Waste Disposal Ordinance (Cap. 354). Our proposed control strategy is summarised as follows:

    --The control scheme on clinical waste will be implemented in two phases. The focus of the first phase will be the collectors and disposers of clinical waste and the major clinical waste producers which include the public and private hospitals and government clinics. The major clinical waste producers generate more than 80% of the total amount of clinical waste in Hong Kong. The first phase of control will be implemented upon the commissioning of Government's disposal facility for clinical waste in early 2000. We intend to extend the control scheme to the remaining clinical waste producers in the second phase.

    --Persons carrying out collection or disposal ("disposal" includes incineration or other technologies approved by the enforcement authority) of clinical waste will be subject to licensing control. A clinical waste producer included under the control scheme will be legally required to arrange for the disposal of his clinical wastes at a licensed disposal facility. A clinical waste producer will be deemed to have met this requirement by arranging either for the collection of his clinical waste by a person licensed to collect clinical waste or for disposal at a licensed on-site or in-house disposal facility. In addition, clinical waste producers under the control will have a duty of care to ensure the proper management of their clinical waste and failure to do so is an offence.

    --A Code of Practice for the Management of Clinical Waste (COP) will be issued under the Waste Disposal Ordinance to provide guidance to all clinical waste producers as well as collection and disposal contractors to ensure that the entire disposal operation will not pose hazards to the workers and the public. Failure to comply with the COP will not be an offence but it could be used as evidence for establishing whether or not a clinical waste producer has met his duty of care responsibilities.

    --There will be a charge on the disposal of clinical waste. The objective of the charging for clinical waste disposal is to recover fully the capital and operating costs associated with the disposal of clinical waste at the approved disposal facility to be commissioned by the Government. Charges will be linked to the quantity of clinical waste delivered to the approved disposal facility to encourage waste minimisation and to minimise cross-subsidies between different waste producers. The charge for disposing of clinical waste will be levied on the licensed clinical waste collectors. It will be the responsibility of the waste producer and licensed collector to negotiate a fee for the collection, delivery and disposal of a consignment of waste taking into account the charge for disposal to be levied by Government.

    --The market for clinical waste collection services will be open to all collectors who meet the prescribed standards.


34.We have approached the medical profession for a preliminary consultation on the proposed clinical waste control scheme. We will also be approaching other relevant parties very soon to collect their views on these proposals. The Administration intends to consult all the affected parties before firming up details of the proposed scheme.

Note 1: None of the pathological waste incinerators meet the current standards laid down under the Air Pollution Control Ordinance (APCO) for pathological waste incinerators. It is necessary to retrofit each of these incinerators if they are to meet the APCO standards.

Planning, Environment and Lands Bureau
October 1997