Agenda Item 1 : 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)
The Chairman briefed Members on the background of the final soil quality report. He said that the Council endorsed the EIA report on the "Kai Tak Airport North Apron Decommissioning" project in 1998 with conditions. One of the conditions was that on completion of the decontamination works and before starting the proposed housing development at the project area, the project proponent should submit the final soil quality report of the previously contaminated areas to the EIA Subcommittee for inspection.[The project proponent team joined the meeting at this juncture.]
2. The Chairman welcomed Mr. H I Kwong et. al. to the meeting. Mr. Kwong explained the purpose of the meeting and Mr. Keith Tsang briefed Members on the findings of the soil quality report.
3. A Member asked whether the project proponent had assessed the risk to workers of the housing development project in Areas 1A and 1B if there was a rebound of contamination in the Hotspots. In response, Mr. Kwong said that the chance of a rebound was very remote. Furthermore, the Hotspots were far from Areas 1A and 1B, the workers in the latter area would not be affected.
4. A Member asked how detailed the site investigation carried out by the Housing Department was. In response, Mr. Kwong said that the surveys conducted by TDD were comparatively much more substantial. The Housing Department advised TDD they had conducted a site investigation and the findings indicated that Areas 1A and 1B were free of land contamination.
5. In response to the Chairman's query on heavy metals at Areas 1A and 1B, Mr. Kwong advised that the areas were already free of land contamination.
6. A Member asked if it was correct to say that the results of the decontamination work in the Hotspots were successful and that no rebound had been found so far. In response, Mr. Kwong said that a post-remediation monitoring for a period of two years was under way. The initial set of readings showed no sign of a rebound. Monitoring would continue and appropriate remediation action would be taken if any rebound was found.
7. In reply to the Chairman's enquiry regarding work planned for areas other than Areas 1A and 1B, Mr. Kwong said that the demolition work of the terminal building was scheduled for commencement in early 2004. In that regard, there would still be adequate time to collect post-remediation monitoring data before the work started.
8. In response to the Chairman's question, Mr. Kwong said that the final soil quality report would be completed in two to three months' time and would be submitted to EPD for scrutiny.
9. The Chairman relayed a Member's questions to the project proponent as follows:
whether there were any discrepancies between the actual contamination and that projected in the endorsed EIA report in terms of the volume, toxicity and locations of the contaminated soil; and
whether there were any residual impacts of heavy metals including chromium 6, a toxic substance that could be transformed from chromium 4 during the treatment process, upon human and the environment and if so, the treatment to be adopted to deal with the impacts.
10. In response, Mr. Kwong said that whilst the volume of contaminated soil was larger than the original estimate and some new hotspots were identified, the level of toxicity of the ground contamination was within expectation.
11. Regarding residual impact of heavy metals, Mr. Matthew Ko said that chromium was identified in the electroplating workshop site. The level of chromium detected was lower than Dutch B standard for total chromium and US Federal standard for chromium 6. The heavy metals were treated by means of cement solidification during which no toxic form was produced. The treatment of heavy metals had already been completed.
12. The Chairman proposed and Members agreed that the Subcommittee had no objection to the construction works in Areas 1A and 1B. The Subcommittee reserved the right to consider the final soil report when it was finalized and submitted to the Subcommittee.
EIA Subcommittee Secretariat