Gas Company Complains On Effluent Limits

Press, Volume CVIII, Issue 31865, 18 December 1968, Page 20

Gas Company Complains On Effluent Limits

Limitations imposed on the discharge of pollution from the gasworks were very harsh, the Christchurch (Jas Company, Ltd, wrote to the Christchurch Drainage Board last evening. The board had specified the lower limit of all impurities set out in a model by-law, it said.

The board retained the standards set last month and asked for information forthwith on action already taken or under way, action proposed and by March 31 a timetable for accomplishing completion of the pollution abatement works by August 31. 1969.

The company was willing to implement any scheme proposed by its consultants, Messrs Steven and Fitzinaurice, that showed promise of effective, economic control of effluent, the letter said. The gas works’ problem was perhaps the most complicated in the board’s area. The British gas industry had studied effluent problems for years but the standards required by the board had never been attained. The company also said the time limits set by the board appeared to be impossible to fulfil because engineering planning in this field was a long process.

While it thought there could be a solution to the problems associated with the stormwater outfall, the solution to the foul waste outfall was still obscure. After saying that a prolonged study had resulted in a report for submission to the gas company, the consulting engineers said some of the board's requirements could not be met readily, nor was the need to do so obvious. The need for a restriction on the discharge of cooling water was not clear, and the consequences appeared unreasonable to the company. The economics of gas manufacture were determined largely by the availability of a market for the by-products, they wrote. A changing market in New Zealand would probably lead to a change in the company’s manufacturing processes so that within the foreseeable future the character of waste products would probably change. Phenols, in particulars, would probably be a reducing element in waste disposal. The board’s chief engineer (Mr P. J. McWilliam) said March 31 had been set for completion of pollution prevention measures and it was fair comment by the company

to say it could not meet this I date. I In setting requirements the i board had an obligation to i ensure that its works, treat- i ment processes and staff i were not endangered, he said, i The upper limit for phenols had been applied to the com- i pany. The limit on the quantity i of cooling water to be dis- i charged had been set at the I

figure the board was told was the company’s present discharge. This could be increased, but the company should be told of the possibility of a charge being made in the future. Mr A. E. Lambden, the chief chemist, said the gas industry in the United Kingdom had met similar standards to those imposed by the board.