Advisory Council on the Environment

Report on the 70th and 71st Environmental Impact Assessment Subcommittee Meetings

(ACE Paper 22/2002)
For advice

INTRODUCTION

At its meetings held on 27 May and 3 June 2002 respectively, the Subcommittee considered the following reports-
 

  (a) EIA report on Fill Bank at Tseung Kwan O Area 137;
 
  (b) EIA report on Improvement to Tung Chung Road Between Lung Tseng Tau and Cheung Sha; and
 
  (c) South East Kowloon Development at Kai Tak Airport - Decontamination and Site Preparation - Final Soil Quality Report of the Previously Contaminated Areas dated 13 May 2002.
 

As directed by the Council at its meeting in December 2001, the Subcommittee also discussed the subject of informal dialogue with project proponents and whether a record of such informal dialogue should be kept.

ADVICE SOUGHT

2. Members are requested-
 

  (a) to advise whether the two EIA reports should be endorsed;
 
  (b) to note the conclusion of the Subcommittee regarding the final soil quality report; and
 
  (c) to note the recommendation of the Subcommittee regarding the keeping of brief notes for informal dialogue with project proponents.

VIEWS OF THE SUBCOMMITTEE

EIA report on Fill Bank at Tseung Kwan O Area 137
(ACE-EIA Paper 7/2002)

Need for the project

3. The Government have identified that from 2002 up to end of 2005, there will be a significant shortfall in public filling capacity in the territory. If the shortfall is not dealt with, useful public filling materials could end up in landfills as wastes. The project will provide temporary fill banks for storage of the public fill.

Description of the project

4. Tseung Kwan O Area 137 is a newly reclaimed area at the southern tip of Tseung Kawn O (TKO), away from most existing and planned sentive uses. A site of 104 ha has been identified to be suitable for the establishment of a temporary fill bank for stockpiling of public fill materials.

5. The proposed fill bank is a designated project under Schedule 2, Part I, Item C.11 of the EIA Ordinance. The project comprises site clearance, construction of a temporary storm water system, stockpiling of 6 million m3 of public fill, setting up of a barging point, and constructing and operating a Construction and Demolition Material Sorting Facility.

Views and recommendations of the EIA Subcommittee

6. Having studied the EIA report and ACE-EIA Paper 7/2002, Members agreed to recommend the EIA report to the Council for endorsement without conditions and a presentation by the project proponent was not necessary

EIA report on Improvements to Tung Chung Road Between Lung Tseng Tau and Cheung Sha
(ACE-EIA Paper 8/2002)

Need for the project

7. The existing Tung Chung Road is sub-standard. It carries a significant proportion of buses and coaches and is experiencing an increasing number of traffic accidents. Although Government have introduced operational controls to maintain safer traffic conditions, improvements to the road are required to rectify the undesirable situation.

Description of the project

8. The project is a designated project under Schedule 2, Item A1 of the EIA Ordinance. The current proposal is an alternative solution to the previously proposed Lantau North-South Link Road.

9. The section of Tung Chung Road from Lung Tseng Tau to Cheung Sha, approximately 6.2km long, will be widened or realigned to provide a 7.3 m wide carriageway and a footpath of 1.6m to 2.0m in width. Bus bays, a taxi stand and u-turn facilities for buses near the junction of Tung Chung Road and South Lantau Road and associated works will be constructed.

Views and recommendations of EIA Subcommittee

10. Members' concerns on the project are mainly the width of the verge and the paved footway along the eastern side of the northern on-line section of the road; operation of the drainage system to collect run-off; the effectiveness of the sedimentation tanks; structures over streams; noise impacts arising from existing roads; translocation programme for the Hong Kong Newt and Beijiang Thick-lipped Barb; ecological value of compensation planting; visual impacts of the project; materials resulting from vegetation clearance; trucking of wastes and overall project management.

Width of the verge and the footway

11. On the width of the verge and the footway along the eastern side of the northern on-line section of the road, the project proponent team explained that the existing verge on the western side of the road was occupied by existing utilities. The carriageway would be occupied by drainage pipes. There would be no room in the carriageway and the existing verge on the western side of the road to accommodate new services required to be laid by the utility companies e.g. gas duct and new cables to replace the existing overhead power lines. The width of 3.6 m for the verge and the footway on the eastern side of the road was the minimum requirement to accommodate those new services and there was no scope for further reduction.

Drainage pipes for collecting run-off

12. On the possibility of the site run-off choking the drainage pipes, the project proponent team pointed out that the main pollutants would be sediments and the diameter of the pipes would be large enough for the sediments to get through. In fact, once there was water in the system it would operate largely on a self-flushing basis.

Effectiveness of the sedimentation tanks

13. A Member considered that the use of sedimentation tanks alone would be unlikely to achieve the standard of 25 ppm for effluent discharge. The project proponent team explained that huge run-off in any one location was not expected as the run-off would be diverted to different directions. Furthermore, the sedimentation tanks and the drainage pipes would be equipped with a filter system, if necessary. The detailed design of the filter system would be worked out in connection with the Environmental Monitoring and Auditing (EM&A) Programme.

14. The project proponent team had considered the use of chemicals to treat the effluent but since the project was partly within the water gathering ground, the conclusion was that the temporary drainage system should be non-chemically based. The project proponent team also confirmed that the southern section of the drainage system would cover the bus bays, taxi stand, etc and would include an oil trap so as to protect the Cheung Sha beach.

Structures over streams

15. A Member expressed concern about the design of structures over the streams and how the impact of run-off on the streams could be minimized. The project proponent team explained that the spans of the bridges would generally be no more than 30 m and it would be possible to use pre-cast beams to minimize construction work on site. Alternatively, they might put false work across the specially designed abutments/piers on both sides of the stream and arrange concrete casting on top of the false work insitu to avoid impacting on the stream. For haul roads crossing streams, temporary bridge which could be lifted on top of the streams would be used. Structures that might have impact on the sensitive streams would be constructed in the dry seasons and non-breeding seasons as far as practicable.

Noise impacts of existing roads

16. On residual noise impact on the section of existing Tung Chung Road outside the project limit, the project proponent informed Members that Highways Department would review the situation upon commissioning of the project and, if necessary, initiate action to include that section of existing Tung Chung Road into the retrofitting programme for existing roads.

Translocation programme

17. A Member sought clarification on the proposal to evacuate and translocate individuals of the Hong Kong Newt and Beijiang Thick-lipped Barb to nearby areas instead of other areas and whether it would assess the effect of the translocation programme before starting the culvert construction works. The project proponent team clarified that the proposed translocation programme was different from the permanent translocation of the Romer's Tree Frog from the Chek Lap Kok Airport project site in which the habitats concerned were permanently destroyed. In the present case, the project would have impact on some habitats of the Hong Kong Newt and Beijiang Thick-lipped Barb on a temporary basis but would not affect a large population of those species. Also, the habitats concerned would be suitable for the species after the completion of the culvert construction works. Hence, it was not necessary to assess the effect of the translocation programme before starting the construction works. Furthermore, it was expected that after completion of the construction works, the population of the Beijiang Thick-lipped Barb from down stream would naturally move upstream, making it unnecessary to have a re-translocation back to the original sites.

18. The project proponent team agreed that the programme to identify and translocate the individuals of the affected species must be rigorous to be effective. The detailed methodology of the programme would be worked out in the detailed design stage. The monitoring on the translocation programme would last for 12 months after the operation of the improved Tung Chung Road.

Ecological value of compensation planting

19. A Member noted that there would be 25 ha of compensation planting to mitigate for the loss of woodland and shrubland, etc. Whilst the compensation planting would mitigate for the loss of visual and landscaping value, it was not certain how it could translate into ecological value. There was similar concern about the ecological value of grass hydro seeding on slope enhancement works and whether there were other alternatives with better ecological value.

20. The project proponent team pointed out that the area of compensation planting was more than double of the loss of woodland and shrubland. This ratio was meant to compensate for the loss of the ecological value of the woodland and shrubland in the long term. As regards slope enhancement works, grass hydro seeding would be adopted for slopes that were too steep for planting of trees. The Geotechnical Engineering Office had promulgated various alternatives of slope enhancement works. The detailed design of the project would determine how to maximize the potential ecological benefit of the compensation planting and slope enhancement works. The off-site compensation planting would commence in parallel with the improvement works and there would be a 12-month monitoring period after planting.

Visual impact of the slope enhancement work

21. Members expressed concern about the visual impacts of the project, particularly at the southern section of the road where there were tall retaining walls. The project proponent team pointed that the retaining walls were meant to reduce the footprint of the project. On the downhill side, planting could be done in front of the retaining walls and creepers would be planted. In the long run, the trees would be able to hide the retaining walls and the road. On the uphill side, further planting was not possible unless the verge of the road was widened. The project proponent assured Members that they would do as much as they could to beautify the artificial structures.

Materials resulting from vegetation clearance

22. A Member asked whether the 4,800 tonnes of materials resulting from vegetation clearance could be recycled for beneficial use rather than to be dumped in landfills. The project proponent agreed to try their best to consider ways to reduce the amount of wastes to be taken to the landfills and liaise with other departments such as AFCD on ways to make better use of those materials.

Trucking of waste materials

23. On the trucking of waste materials, the project proponent team indicated that the trucks would avoid going through residential areas. Based on the amount of traffic in Tung Chung Road at the moment, the trucking of waste materials would not be significant and would be temporary in nature. Furthermore, the existing road was subject to control and the number of trips in rush hours would be restricted.

Overall project management

24. The project proponent team noted Members' concern about poor site practices of some projects in Lantau Island in the past and the need for a robust EM&A programme and effective management of the contractors.

Conclusion

25. After detailed discussion, the Subcommittee concluded that the Subcommittee would recommend the EIA report to the Council for endorsement with the following proposed conditions-
 

      (a) there would be a robust EM&A programme to improve the effectiveness of the sedimentation tanks and appropriate measures (such as filter system) should be incorporated, if necessary; and
  (b) the project proponent should liaise with AFCD and other Government departments on the beneficial use of the materials resulting from vegetation clearance so as to reduce the amount to be taken to the landfills.

South East Kowloon Development at Kai Tak Airport - Decontamination and Site Preparation - Final Soil Quality Report of the Previously Contaminated Areas
(ACE-EIA Paper 9/2002)

26. In 1998, the Council endorsed the EIA report on Kai Tak Airport North Apron Decommissioning with conditions. One of the conditions requires the project proponent to submit to the EIA Subcommittee a report on the final soil quality of the previously contaminated areas before starting the proposed housing developments.

Views and recommendations of the EIA Subcommittee

27. The Subcommittee considered the Final Soil Quality Report dated 13 May 2002. Members noted that the project proponent had completed the decontamination works in previously contaminated areas within Kai Tak north apron and had complied with targets specified in the approved EIA report or standards agreed by Environmental Protection Department. Post remediation monitoring for checking of any rebound of ground contamination at those areas was underway. There is so far no indication of rebound. Monitoring would continue in accordance with requirements in the EM&A Programme. The Final Soil Quality report would be finalized in about two months' time.

Conclusion

28. The Subcommittee noted that housing development at sites 1A and 1B outside the contamination hotspot areas would start in July 2002. Ground contamination had previously not been found in those two sites and recent site investigation by the Housing Department also confirmed that there was no land contamination in those areas. After discussion, the Subcommittee agreed that it had no objection to the Housing Department proceeding with housing development at the two sites. The Subcommittee would consider the Final Soil Quality report when it is finalized and made available to the Subcommittee.

Informal dialogue with project proponents

29. The Subcommittee discussed the subject of informal dialogue with project proponents and agreed that it was not necessary to keep detailed minutes of meeting for informal dialogue as for regular Subcommittee meetings. Instead, a record in the form of brief notes on issues discussed should be kept for the internal reference of Members. The notes would not be circulated to project proponents.

EIA Subcommittee Secretariat
June 2002

 

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