Paper manufacturers are under growing pressure to find new outlets for some 1.75 million tonnes per year of paper sludge, which is generated largely from recycling operations. Most of the waste is spread on agricultural land, but the practice is often unpopular with local communities because of odours and traffic nuisance (ENDS Report 278, pp 28-29 ).
Legislation to tighten controls on land spreading is in the offing at both national and EU level. The alternative, landfill, is becoming increasingly expensive, not least because of the £12 per tonne landfill tax.
Another problem this year is that companies have been unable to obtain access to many planned spreading sites because of the foot and mouth outbreak.
Anxious to find alternative outlets for its waste, SCA Hygiene has been working with consultancy ADAS to explore the use of sludge to make topsoil for colliery spoil tips. Contributing organic matter and lime to the acidic soil, the sludge can help restore such sites to public amenity status. The company has spent two years restoring a site at Shilbottle in Northumberland using paper sludge.
Officials at the Environment Agency's office in Newcastle were involved in the Shilbottle trial and approved the use of paper sludge under an exemption from the waste licensing regulations covering composting activities or other biological transformation process involving materials spread on land. Agency officers are said to have been impressed by the improvement at the site.
ADAS, operating through its "Envar" business, sought the Agency's go-ahead to extend the sludge spreading activities to other colliery sites. Trials began at Ashington in the north-east. Exemptions under the waste licensing regime were also registered for three sites in south Yorkshire.
But in July 2000, ADAS was told that Agency lawyers had questioned whether using sludge in this way constituted "composting". ADAS took legal advice and responded that the sludge was biologically transformed in the process and that the activity brought ecological improvement - the key requirements for an exemption from licensing.
However, in a letter to ADAS last June, the Agency's regional waste manager for the north-east, Offord Slater, said that it "does not agree that your proposed activities are currently covered by any of the waste management licensing exemptions." The Agency's Rotherham office subsequently rescinded the registrations it had allowed for collieries in south Yorkshire.
Mr Slater added that the Agency had recommended to the Environment Department that it should add paper sludge to the list of materials which can be used for restoration of industrial land without requiring a waste licence.
The Agency's proposal, if accepted, would solve SCA's problem. But the matter is tied up with the ongoing Whitehall review of the waste licensing exemptions, which has been promised since 1998 but postponed for various reasons - the latest of which is that officials have been busy dealing with the foot and mouth crisis. A consultation paper was due to be published in September and may now appear in October.
SCA has abandoned the colliery projects for the time being. The alternative of applying for a waste licence was judged to be too costly and time consuming.
As a result, some 60,000 tonnes of sludge from a mill in north-east England and another 36,000 tonnes from one in Derbyshire are now going to landfill.
Colin Rudd of ADAS says that he is upset with the Agency's "intransigence" over the issue and its failure to support an operation that is more environmentally beneficial than sending sludge to landfill. He is also "intensely frustrated" by the Environment Department's delays in reviewing the waste licensing regulations.
His frustration is shared in the paper industry. David Gillett, technical manager for the Confederation of Paper Industries (CPI), said that the case showed that "the law has not kept pace with developments on the ground."
Mr Gillett conceded that the industry had "a problem with quantities" of paper sludge as recycling expands. Several "big solutions" are needed, he said, but none is in sight.
ADAS estimates that there are enough suitable sites in the UK to take about 0.5 million tonnes of sludge per year. For the remaining 1.25 million tonnes, spreading on agricultural land remains the preferred option. Some work is in hand to look at ways of composting the sludge before applying it to farmland, but this is likely to be costly.
ADAS has also experimented with mixing paper sludge with other wastes, such as foundry sand, to produce "soil-making materials", but it is likely that this too would fall foul of the waste licensing regulations.
Aylesford Newsprint has led the way in burning dried sludge in a combined heat and power project in Kent, but the recent hike in gas prices has discouraged other companies from adopting the option, according to Mr Gillett. He said that "individuals" in the Agency had pressed the industry to embrace energy from waste, but it remained to be proven that it was the best practicable environmental option.
Paper companies accept that when DEFRA's consultation paper is eventually published it is likely to tighten standards for sludge spreading on agricultural land. Such changes were foreshadowed by a review for the Agency carried out in 1998 (ENDS Report 281, pp 27-29 ).
The European Commission is also working on a Directive on the biological treatment of biowaste which is likely to require stricter management of sludge wastes (ENDS Report 314, pp 51-52 ). According to Mr Gillett, however, this need not impede the practice.