The release of the consultation paper on solid waste treatment will be delayed by at least five months since more time is needed to prepare it, it was disclosed yesterday. Legislator Choy So-yuk revealed the delay after a meeting with environment secretary Sarah Liao Sau-tung, in which Ms Choy gave the views of her party, the Democratic Alliance for Betterment of Hong Kong, on the issue. Ms Choy said Dr Liao told her the government wanted to 'enrich' the potentially controversial document by considering more suggestions. The document was originally expected to be released next month. But now it will not be released until September at the earliest, a spokeswoman with the Environment, Transport and Works Bureau confirmed last night. 'As the document [should] be comprehensive, more time is needed,' the spokeswoman said. She rejected suggestions that the delay was related to the change in government following Tung Chee-hwa's resignation. No firm date had been given for the release of the paper on the planned integrated waste treatment strategy, but some officials had said it could be out as soon as next month. Ms Choy said she told Ms Liao that the DAB would not oppose thermal methods such as incineration or gasification - which turns waste into gases at extremely high temperatures - provided they were environmentally safe. But she said thermal treatment should not be used for all garbage: mechanical waste-sorting and recycling should also be used. Ms Choy said such methods were needed since waste separation at source alone might not be effective enough. It is estimated that less than 20 per cent of solid waste - mostly un-recyclable waste or toxic materials - would need to be burned. The DAB also called for introducing a domestic waste-disposal charge, based on the amount generated, to reduce the production of waste. Surcharges should also be imposed on products containing toxic substances, forcing manufacturers to improve their designs. The party also supports pilot schemes to require producers or importers to take back their used products, such as rubber tyres and plastic bottles. In the long term, it says certain types of waste, such as foams or toxins, should be barred from landfills. Laws similar to the European Union's directives on controlling hazardous or contaminated contents in products could also be enacted locally.