The city's only incinerator that can handle hazardous waste is chronically underused and may have to be moved from Tsing Yi or scaled down.
The Environmental Protection Department plans to hire a consultant to look into the future of the facility. It will direct the consultant to study the incinerator's operation, and whether it needs to be downsized or relocated to other locations such as to a rock cavern or reclaimed land.
The consultant will also be asked to forecast the extent of chemical and hazardous waste requiring treatment in the next 15 to 20 years, taking into account import and export controls on such waste and advances in technology, according to a tender document seen by the South China Morning Post.
The plant was commissioned in 1993 and can handle 100,000 tonnes of chemical or toxic waste per year.
However, only 10 per cent of that capacity was used last year, according to figures provided by the department.
About 7,000 tonnes of chemical waste was treated at the incinerator last year. That compares with 50,000 tonnes in 1994, the year after it opened.
It handled 2,700 tonnes of waste oil from vessels last year, versus 47,000 tonnes in 1998.
The department is commissioning the study ahead of the release of its new waste management blueprint, and halfway through the operator's 10-year contract. Key to the new plan for tackling the city's waste disposal problems will be determining whether to install infrastructure such as a waste-to-energy incinerator to treat waste that cannot be recycled.
Professor Wong Woon-chung, a waste specialist from Baptist University, said a facility dedicated to treating hazardous waste was essential for the city, but its size and location should be reviewed. "The facility was built 20 years ago when there was not much nearby on Tsing Yi. Now, the island is home to about 200,000 people and there is a need to review whether it is desirable and safe," he said.
The incinerator occupies a two-hectare site on southeastern Tsing Yi, close to the Kwai Tsing dock from where it collects oily or noxious liquid waste from ocean-going vessels. Under international maritime rules, port authorities are obliged to provide disposal outlets for vessels' waste.
The area is on the doorstep of an old industrialised district of Tsuen Wan and Kwai Chung, which were once the main sources of chemical waste such as lubricants or spent electrolytic solutions. The plant began handling clinical waste in 2011, in a bid to increase its use. It treated 2,044 tonnes last year.
And it would also provide emergency services in the case of chemical or biological contamination - or a new virus outbreak.
Kwai Tsing district councillor Tam Wai-chun said she had not received any complaints about the incinerator from residents, but would support its relocation. "Who wants something like this in their backyard? It's just like the urn niches - no one wants them as neighbours either," she said.