Confirmed Minutes of the 68th Meeting of the Environmental Impact Assessment Subcommittee of the Advisory Council on the Environment held on 4 March 2002 at 4:00pm

In Attendance for Agenda Item 2 & 3:

In Attendance for Agenda Item 4:

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The Chairman informed Members that the draft minutes of the last two meetings were not yet ready and the confirmation of which would be deferred to the next meeting.

Agenda Item 1 : Matters Arising

2. There were no matters arising from the last two meetings.

Agenda Item 2 & 3 : Yau Tong Bay Development - Engineering Feasibility Study for Comprehensive DevelopmentYau Tong Bay Development - Reclamation of Yau Tong Bay
(ACE-EIA Paper 3/2002 & 4/2002)

3. The Chairman welcomed the presentation team led by Mr. Augustine Wong. Mr. Thomas Tang briefed Members on the EIA.

4. In response to the Chairman's enquiry, Mr. David Cox said that the West Coastal Road would be subject to a separate EIA study which was anticipated to be completed by 2003. The project proponent, Territory Development Department, would consult ACE on the EIA report.

Industrial/Residential interface

5. The Chairman referred to paragraph 1.2.6 in the Executive Summary of the Engineering Feasibility Study for the Comprehensive Development at Yau Tong Bay which stated that "Lands Department will terminate all polluting activities currently operated on the Dissenting Lots under short-term waivers" and asked about the number of establishments operating under short-term waivers on the dissenting lots. In reply, Mr. Augustine Wong said that none of the polluting activities operating in the dissenting lots was under short-term waiver. He apologized for the confusion caused by the Executive Summary. 6. The Chairman asked how one could be assured that the proposed mitigation measures would be adopted. In response, Mr. Tang said that the contractors would be required to comply with the terms under the environmental permit and related environmental regulations. Mr. Augustine Wong supplemented that since the site was zoned as Comprehensive Development Area (CDA), the Government had the authority to control the development through the Town Planning Board which was responsible for vetting and approving the Master Layout Plan for the development project. The Government could also include in the land lease that the design and the mitigation measures should be subject to the satisfaction of EPD.

7. Mr. Lin Chaan-ming expressed concern about the noise and air impacts to future residents in the area and enquired about the distance between the dissenting lots and the nearest residential building. In response, Dr. Westwood Hong said that there was a buffer zone of at least 60m between the two areas. The noise impact would be within statutory limits. Dr. Pong Lai supplemented that there was no air emission from Wing Shan Industrial Building. As far as the dissenting lots in the northwest corner were concerned, the assessment showed that the emission would not result in any unsatisfactory impact for sensitive receivers in the area.

8. The Chairman asked whether the owners of the dissenting lots could change the nature of their business. In reply, Mrs. Shirley Lee explained that new industries involving "specified process" would require the approval of EPD before they could operate in the dissenting lots. Wing Shan Industrial Building was quite old and most of the tenants had already moved out. It was quite unlikely that establishments involving "specified process" could operate in the type of industrial building that occupied the dissenting lots.

9. In response to Mr. Peter Lee's enquiry, Mr. Augustine Wong said that Wing Shan Industrial Building was mainly used as small offices and storage areas and about thirty-odd percent of the units were vacant.

10. In reply to Mrs. Mei Ng's enquiry, Dr. Pong Lai said that the materials stored in Wing Shan Industrial Building were mainly timber and other construction materials which were non-hazardous. Mr. Peter Lee asked whether the timber contained any hazardous preservatives like borax. Mr. Szeto Wang, an operator in shipbuilding industry, said that the timber used for shipbuilding would undergo very long treatment process and by the time they were ready to be used they did not contain any harmful preservatives.

Sewage disposal

11. Mr. Peter Lee expressed concern about adverse impacts on the water quality of the Victoria Harbour arising from the sewage flow from Yau Tong. In response, Mr. Alex Kwan pointed out that the estimated population of the future Yau Tong Bay area would be about 40,000. The EIA had assessed the capacity of the Kwun Tong Preliminary Treatment Works (KTPTW) and concluded that it could accommodate the sewage from Yau Tong area which would only take up about 4% of the total capacity of the facility. The sewage screened in the KTPTW would be piped to the Stonecutters Island for enhanced treatment and discharged through the existing outfall. Mrs. Shirley Lee said that the disposal of sewage in Hong Kong must comply with the Water Pollution Control Ordinance. The Harbour Area Treatment Scheme (HATS) being undertaken would ensure that sewage would be collected and treated properly before discharge.

12. In response to the Chairman's follow up question, Mr. Alex Kwan confirmed that the treated sewage from Yau Tong Bay area would not have any adverse impacts on the water quality of Victoria Harbour.

Land contamination

13. Mrs Mei Ng enquired about the baseline for health, safety and environmental monitoring, the classification adopted for hazardous materials such as asbestos and the quantity of such materials to be handled in the project. In response, Dr. Pong Lai said that they had carried out investigations on the site and taken soil samples to assess the estimated volume of contaminants such as TPH, heavy metals, polychlorinated biphenyls (PCB) and mercury. The anticipated total volume of contaminated soil was about 21,260 m3. They would carry out an assessment on asbestos before the buildings were dismantled and would follow the statutory procedures set out in the Air Pollution Control Ordinance (Asbestos) Regulation in the disposal of asbestos. The classification adopted for the assessment was Dutch B standards.

14. Mr. Lin Chaan-ming pointed out that PCB and mercury were toxic substances which should be subject to special treatment before disposal. He noticed in the EIA report that the two contaminants would be disposed of in landfills without any prior treatment. He asked whether that would conform to international practice. In response, Dr. Pong Lai explained that the estimated volume of PCB and mercury contaminated soil was 1,230m3, of which only about 10m3 contained mercury. The mercury-contaminated soil would be put inside polythene-lined drums and would go through the Toxicity Characteristic Leaching Procedure (TCLP test). Upon passing the TCLP test, the soil would be disposed of in landfill. He emphasized that all the procedures would be carried out in accordance with EPD requirements.

15. Mr. Otto Poon asked whether the prescribed process could lock PCB and mercury into a reasonable safety standard suitable for landfill disposal. In response, Mrs. Shirley Lee said that the amount of PCB and mercury in question was small. According to the guidelines under PROPECC Note regarding remediation of contaminated sites, it was safe to dispose of the soil it in the manner described by Dr. Pong Lai.

16. Prof. Anthony Hedley asked about the efficiency of the process in recovering the contaminants from the soil. In response, Mrs. Shirley Lee clarified that the purpose of the site investigation was to obtain an estimate of the contaminants and delineate a plan for remediation. Under the environmental permit, the project proponent would be required to carry out a detailed site investigation to ascertain the amount of contaminants. The information would form the baseline for monitoring required by the EM&A Manual. The project proponent would also be required to test the treated soil before disposal. In the decommissioning of Kai Tak Airport project, the Government required the project proponent to provide funding for the collection and analysis of soil samples by an accredited laboratory to verify the work of the project proponent and to ensure that the site was properly cleaned up to acceptable standards. She suggested that the same arrangements should be proposed for the present project.

Visual and landscape impacts

17. Dr. Ng appreciated that the project proponent had committed in the report that there would be "high quality landscape treatment and¡K a distinctive character for the new development". However, he did not consider the layout plan attached to the report particularly impressive. In response, Mr. Augustine Wong said that the attached plans were just draft plans. The Master Layout Plan would be subject to the approval of the Town Planning Board.

Recommendations of the Subcommittee

18. The Subcommittee agreed to recommend the full Council to endorse the EIA report with the following conditions:

Agenda Item 4: Decommissioning of Cheoy Lee Shipyard at Penny's Bay
(ACE-EIA Paper 5/2002)

19. The Chairman welcomed the presentation team led by Dr. C K Lau. Dr. Lau briefed Members on the findings of the EIA study.

20. In response to the Chairman's question, Mr. Simon Hui said that the reports from Maunsell and URS were submitted by the project proponent under the EIA Ordinance as one EIA report. Mrs. Mei Ng asked whether other "independent" reports on the project would be submitted in the future. Mr. Hui said that the reports which should be considered by the Subcommittee were those currently submitted by the project proponent. In response to Mrs. Ng's enquiry, Mr. Elvis Au said that the Civil Engineering Department was the project proponent of the project.

21. At the invitation of the Chairman, Members highlighted the issues of concern as follows :

Comparison between thermal desorption and direct incineration at CWTC

22. Mr. Matthew Ko drew Members' attention to a table on the capacity of the Tsing Yi Chemical Waste Treatment Centre (CWTC) and the cost required in incinerating dioxin-contaminated soil (Annex 1). He said that though CWTC had spare capacity, it was designed for treating liquid rather than solid contaminants. Without any modification, CWTC would take about 90 years to incinerate 30,000 m3 of dioxin-contaminated soil. Minor and major modifications would shorten the process to about 18 years and about 3.5 years respectively. The implications of those scenarios were that the contaminated soil had to be stored in another site. In addition, there would be higher secondary pollution risk in transporting 30,000m3 dioxin contaminated soil to CWTC. As a contrast, only 600m3 of condensate (residual from thermal desorption) would be transported to CWTC. Besides, incinerating 30,000m3 dioxin-contaminated soil would have more adverse impact on air quality. It was considered that thermal desorption would be a better option for treating dioxin-contaminated soil.

23. In response to the Chairman's enquiry, Mr. Matthew Ko said that the risk of having a traffic accident of transporting contaminated soil was higher than transporting condensate because the former required a greater number of trips. Safety measures such as speed limit and escort would be implemented to reduce the risk to the minimum.

24. Mr. Lin Chaan-ming asked whether the consultant had considered alternative technologies like base catalyst dechlorination. In reply, Mr. Matthew Ko said that a comparison between all known feasible methods were included in Table 4.51 of the report. It was less costly for CWTC to incinerate condensate than building a base catalysed dechlorination plant. Moreover the dechlorination process would generate five times more chemical waste and the waste would require further treatment at CWTC.

25. Mrs. Mei Ng said that she had studied the technologies quoted in the EIA report but found that only two had handled dioxin as the principal contaminant and there was yet no monitoring data to prove their effectiveness. In response, Mr. Matthew Ko explained that thermal desorption had been widely used since 1987 to treat different types of contaminants including chlorinated compounds which were similar in nature to dioxin. In the last 10 years, there were 170 projects using thermal desorption, 20 of which had dealt with dioxin contaminants. The project in the Olympic site in Australia was successfully implemented and the treatment plant decommissioned. Another example was the plant in Jacksonville run by the United States Environmental Protection Agency. The operation of that plant was subject to very stringent requirements and the monitoring data showed that the treated soil and emissions had consistently met the required standards.

In-situ capping

26. Dr. Ng Cho-nam asked whether it was possible to leave the dioxin contaminated soil in-situ. In reply, Dr. Lau said that in-situ capping was a feasible option but the environmental risk would remain on site and affect the future land use. It was considered that the issue should not be left to the next generation.

27. Mr. Otto Poon asked about the half-life of dioxin. In reply, Mr. Matthew Ko said that given an engineered environment, dioxin would take about 10 years to complete the biodegradation process but the length of time would vary with the initial concentration of dioxin. He then invited Prof. Jonathan Wong, a reviewer of the EIA report, to give his views on different treatment methods on dioxin.

Alternative technologies

28. Prof. Jonathan Wong said that biodegradation was feasible but the time needed for the process was uncertain. The technology was still immature at the present stage. Incineration could break down dioxin into carbon dioxide under a temperature higher than 1200 oC and was widely practiced in overseas countries. As regards thermal desorption, dioxin was released and condensed during the process but the dioxin condensate required further treatment. Treatment of other kinds of chlorinated hydrocarbon by thermal desorption was demonstrated as workable but for dioxin, there were only three examples in the world. In his opinion, incineration was the best option but thermal desorption under proper management was also a good option.

29. In response to the Chairman's enquiry, Prof. Jonathan Wong said that the only plant in Hong Kong capable of incinerating dioxin-contaminated soil was CWTC but substantial upgrading would be needed.

Transportation of contaminated soil 30. On the justification for selecting To Kau Wan (TKW) as the site for the thermal desorption plant, Mr. Eric Ma said that the site, about 4km away from the theme park, was of low ecological value and remote from sensitive receivers. The transportation route would not trespass any public express roads or highways. To minimize the risk of secondary environmental impacts during transportation, only dedicated roads and local roads would be used. The truck would be accompanied by escort vehicles in front and at the back to reduce the risk of accidents.

Contingency plan

31. Mr. Ko said that since the contaminants were of low VOC level, the risk of explosion was extremely low. The whole operation of thermal desorption would be controlled and monitored by a computer system. It would automatically shut down if emissions were detected to contain toxic elements exceeding the standard. In addition, the contractor would be required to submit a detailed hazard study report during the design stage of the project.

Parallel operation of the thermal desorption plant and the theme park

32. Dr. C K Lau informed Members that the decommissioning of the thermal desorption plant in 2006 represented the worst-case scenario. The treatment plant could most likely be decommissioned earlier and they would consider specifying that in the contract. The treatment process and the decommissioning of the plant would comply with all environmental legislation and requirements and would have no effect on the activities of the theme park, even if they lasted beyond the opening of the theme park.

Safety measures of the thermal desorption plant

33. Mrs. Ng was not satisfied why on site treatment of contaminated soil was not possible. She had grave concern over the secondary impacts arising from transporting contaminated soil to the treatment plant using roads in close proximity to a highway and a water body. In response, Mr. Eric Ma explained that they had already maximized the amount of contaminated soil to be treated on-site. The dioxin-contaminated soil which required off-site treatment would be transported in roll-off trucks and the route would not pass through any expressways or highways. Mr. Matthew Ko supplemented that dioxin was not water-soluble and would not be carried away easily in storm or rainwater runoff. The wastewater treatment system at the thermal desorption plant would control run-offs at site. As regards the risk of dioxin dispersing by wind, the modeling of emissions from the plant was based on a worst-case scenario and the result was 300 times lower than the standard.

[The Subcommittee retired to another room at this juncture to discuss whether another meeting would be required.]

34. The Chairman informed the project proponent that another meeting would be convened tentatively on 18 March 2002 at 4:00pm to continue the discussion of the EIA report.

35. Members then listed out subjects that they wished to discuss further at the next meeting. Mr. Lin suggested the topic of the cost-effectiveness of thermal desorption. Mrs. Ng requested for details of the contingency plan and the costs involved; risk assessment on transportation of contaminated soil and the decommissioning of the treatment plant, and alternative sites considered for the treatment plant. Dr. Ng would like to know the risk involved in case of spillage of contaminated soil. Miss Yau would like to discuss the ecological impact on rich fish and the proposed mitigation measures for Mong Tung Hang Stream.