Toxic wastes shock-load?

Press, 4 December 1981, Page 4

Toxic wastes shock-load?

Dumped toxic wastes are the suspected cause of a serious failure at the Christchurch sewage-treat-ment works last month. Laboratory staff at the Christchurch Drainage Board are investigating the partial break-down of the plant digesters which has led to a rash of smell complaints from residents near the Pages Road site. The board’s chief chemist, Mr A. M. Damen told the board’s operations and services committee yesterday that the failure could have been caused by a shock-load of toxic wastes dumped into the sewer system. Tests had ruled out toxic metals but

volatile acids were another possibility. Board members expressed grave concern about the potential health risk if the sewage-treatment plantbroke down completely. The committee recommended that the board’s engineer, Mr H. P. Hunt, investigate approaching the police or engaging a security patrol firm to catch illegal dumpers. Board members also asked for an investigation into monitoring industrial toxic wastes and installing back-up equipment at the treatment works. The board’s chairman, Mr C. H. Russell, said that the digester problem highlighted

the danger which could result from the irresponsible dumping of toxic wastes. “The whole of the plant was in serious jeopardy and the whole of metropolitan Christchurch at great risk." he said. Mr Hunt said that the plant digesters started to fail on November 19. Staff were forced to reduce the load by discharging small amounts of sewage into the treatment ponds. “Inevitably a smell started to arise,” he said. Raw sewage was still going into the ponds but he hoped that the digesters would be working normally within a few ..days. Masking agents had been

spread on the ponds to try to reduce the smell. A report by Mr Hunt said that the toxic material coming down the sewers was the apparent cause of the digester problems. Land between Bexley and the South New Brighton bridge is the board option favoured for a bird hospital. The committee recommended that the board investigate the nature reserve site on behalf of the Avian Welfare Project which wants to start a wild bird hospital and refuge. The board owns land in the area which could be available or used in negotiations with the Christchurch City Council.