SEQ recycled water - Cyanide to be recycled for drinking water in Queensland ...

Excerpt from the Australian:

Cyanide to be recycled for drinking water in Queensland

11 November 2008

A wide range of industrial contaminants including cyanide, pesticides, grease and fertilisers can be included in waste that will be recycled as drinking water for the 2.6 million residents of southeast Queensland.

The Bligh Government insists the contaminants will not pose a health risk as the levels are low.

Industrial and hospital effluent dumped in the sewers of Brisbane and Ipswich will constitute 12 per cent of the wastewater to be recycled.

The first recycled water will be pumped to Wivenhoe Dam, Brisbane's main storage facility, in February. The quantity will rise from 60 to 230 megalitres per day next year.

Brisbane City Council guidelines covering the disposal of so-called trade waste to the sewer stipulate maximum levels for a wide range of contaminants.

The guidelines are designed to "protect the environment, the health of sewerage workers, the operation and maintenance of the conveyance system and wastewater treatment facilities".

The guidelines have not been amended to take account of the recycled water plan.

Six toxic organochlorine pestides, including DDT and dieldrin, are allowed in trade waste at very low levels -- up to 0.1mg/L. Organochlorine pesticides have been banned because of human health concerns and remain in the environment for many years.

Higher levels of less toxic organophosphate pesticides including malathion and azinphos can be dumped, along with up to 50mg/L of formaldehyde and 30mg/L of petroleum hydrocarbons. The council guidelines say formaldehyde and petroleum hydrocarbons can "adversely affect the safety of operations and maintenance personnel".

The guidelines list 13 allowable metals including arsenic, lead, mercury, cobalt and zinc.

Bromine, sulphide and cyanide, which "may produce toxic atmospheres in the sewer", are allowed, as are ammonia, nitrogen, phosphorous, and grease and oil. The guidelines allow "gross solids" to be dumped if they are less than 20mm.

Treatment processes that may be required before dumping in the sewer include the neutralisation of acidic wastes and the chemical reduction of chromium.

Food preparation wastes must pass through an approved grease trap before reaching the sewer.

Polluted water from the motor trade may result from the degreasing of mechanical parts, the washing of workshop floors contaminated with hydrocarbons, and removing paint wastes from smash repair shops.

Queensland Water Commission chief executive John Bradley said trade waste controls prevented hazardous material from entering sewage networks.

"Councils issue approvals for trade waste after considering the relative risk of the waste to the sewage treatment system and the effluent water quality," Mr Bradley said.

Referring to a mix-up at the Gold Coast's Pimpama treatment plant that resulted in unsafe recycled water being put in drinking water, Mr Bradley said the Western Corridor Recycled Water Scheme was safe. "The system that will produce purified water will have real-time online monitoring that will shut down the plant immediately if regulated standards are not being met."

Launching an advertising campaign for the introduction of fluoridated water, Premier Anna Bligh said the only thing that would stop the recycling plan would be overflowing dams.

"This is something that we can be proud of, not fearful of," Ms Bligh said.

Opposition Leader Lawrence Springborg said recycled water should be used for drinking only as a last resort, echoing the sentiments of National Health and Medical Research Council water chief Don Bursill, which were reported in The Australian yesterday. "If something goes wrong, there's a breakdown in the system; you've got nowhere to go," Mr Springborg said.

See - Cyanide to be recycled for drinking water in Queensland.