§ Mr. Beggsasked the Secretary of State for Northern Ireland what is the volume of sewage sludge which has been transported to and dumped at the East Antrim coastal area of Drain's Bay, Larne, in each of the last five years for which records are available; and how much of the above sewage sludge originated outside Larne borough council area.
§ Mr. Chris PattenFigures for the volume of sewage sludge from septic tanks and small sewage treatment works transported by tanker to the retention tank at Drains Bay (Black Cave North) before discharge at the sea outfall are available only for the years 1982, 1983 and 1984.
44W
Gallons in 000's (approx) 1982 1983 1984 Sludge transported by tanker to Black Cave North 1,008 1,270 832 Volume originating outside Larne borough council area 481 615 398
§ Mr. Beggsasked the Secretary of State for Northern Ireland how many different types of major sewage disposal schemes for Larne are under consideration at this time by the Department of the Environment; what is the estimated cost of each scheme; and how effective each scheme has been evaluated to be in sewage treatment.
§ Mr. Chris PattenTwo major sewage disposal schemes for Larne are under consideration. One scheme involves the construction of retention tanks at Redlands industrial estate which would discharge the town sewage to the sea through the existing outfall at Sandy Bay in suitable tidal conditions. The cost of this scheme is estimated at £935,000.
An alternative scheme would involve discharge of the town sewage through a new outfall in the Black Cave area. A marine survey will be required to confirm the suitability of this proposal and until this has been assessed, no estimate of cost can be made.
In both cases the effluent will be processed to remove or break up solid materials. It is common practice at coastal sites throughout the United Kingdom, where dilution factors and dispersion patterns are favourable, to discharge sewage after such treatment via submarine outfalls.