LCQ11 : Contaminants arising from reclamation works properly handled

Following is a question by the Hon Leung Fu-wah and a written reply by the Secretary for Health, Welfare and Food, Dr Yeoh Eng-kiong in the absence of the Secretary for the Environment, Transport and Works, at the Legislative Council meeting today (December 3) :


Regarding the reclamation projects in progress, will the Government inform this Council:

(a) of the details and progress of the projects;

(b) whether the projects involve the disposal of carcinogenic substances; if so, of the project names and the routes along which carcinogenic substances are transported; and

(c) of the authorities' control measures to ensure that carcinogenic substances are properly disposed of?


Madam President,

(a) The on-going projects in Hong Kong involving reclamation works are shown in the attached Annex.

(b) Except for the projects "Central Reclamation Phase III" and "Reclamation Works in North Tsing Yi", all other projects listed in the Annex do not involve handling and transportation of carcinogenic substances.

For the project "Central Reclamation Phase III", there are carcinogenic substances (eg. some heavy metals and organic polyaromatic hydrocarbons (PAH)) identified in the dredged materials.  Since these substances exist in a form that cannot be released in open air unless being exposed to an environment over 700 degree Celsius, the contaminated sediments are dredged and disposed of at East Sha Chau contaminated mud pit in the usual manner.

For the project "Reclamation Works in North Tsing Yi", some of the contaminants found within the site are classified as carcinogenic, eg. some heavy metals, PAH and polychlorinated biphenyl (PCB).

Decontamination works for heavy metals and PAH are carried out on site.  After treatment, all the soil will be used as backfilling materials for land formation in this project and there will be no transportation of treated materials off site.  For PCB, only a relatively small amount of the contaminated soil handled in this project (about 800m3 out of the total of 90,000m3) has been found contaminated with this substance and the concentration of it is very low (2.3mg/kg).  Pursuant to the United States Toxic Substances Control Act, additional disposal requirements will only be required for soils contaminated with PCB at a concentration greater than 50mg/kg. Therefore, according to the findings and recommendations in the Environmental Impact Assessment Study for the project, the PCB contaminated soil in this project has been disposed of at the Southeast New Territories landfill.  The soil was properly covered during the course of transportation by dump trucks via major road network.

(c) For the project "Reclamation Works in North Tsing Yi", the Government implements the following monitoring measures for all on-site treatments of contaminants :-

(i) An independent environmental monitoring and audit contractor is employed to implement the Environmental Monitoring and Audit Programme approved by the Environmental Protection Department to ensure that there is no adverse impact to the environment due to the treatment processes carried out on site.

(ii) An independent specialist laboratory is employed to ensure that the decontamination works carried out by the contractor were up to the required standards.

(iii) A specialist consultant is employed to help site supervision and to give advice to the Government for the decontamination works.

For the project "Central Reclamation Phase III", the contaminated mud is disposed of at the East Sha Chau contaminated mud dump site.  At this contaminated mud dump site, the Government has a very comprehensive environmental monitoring programme to detect the possible impacts arising from the disposal of contaminated mud.  The monitoring programme includes the monitoring of sediment, water quality, ecological community structure, fishery resources and biotic tissue contamination.  Based on the information collected, the Government conducts ecotoxicology and risk assessments for both human beings and dolphins.  The risk assessment conducted in early 2003 concluded that the risk of the general population and fisherman in acquiring cancer or non-cancer chronic diseases due to eating seafood from the East Sha Chau area is low and within the acceptability guidelines.  The assessment also found that the health risks of eating seafood from the East Sha Chau area were similar to those from other areas in Hong Kong.

End/Wednesday, December 3, 2003