The Agency has yet to authorise any of the new incinerators which secured Intervention Board contracts last year to burn cattle killed under the Over Thirty Month Scheme (OTMS). So far it has received seven applications. The Agency regulates larger incinerators burning more than one tonne per hour, scores of which would be needed to dispose of the 800,000 OTMS cattle to be killed each year (ENDS Report 268, pp 19-23 ).
"We now expect to be in a position to handle applications for authorisation," said Dr David Slater, the Agency's Director of Environmental Protection, at the launch of its BSE risk assessment report on various waste management options. The Agency has been waiting for the report before authorising any new processes - whether power stations burning tallow and meat and bone meal (MBM) produced in rendering plants, or incinerators burning carcases directly.
Dr Slater said: "The risks are so low that we would not choose [between options] on safety grounds. We would have to judge on the grounds of environmental protection, and we'd like to use the waste as an energy source rather than for straight disposal."
The revised rules on animal incinerators issued by the Agency follow local campaigns against plants without abatement equipment which have led several councils to refuse planning permission. The Agency now says that abatement systems to bring particulate emissions below 25mg/m3 and hydrogen chloride below 30mg/m3 are "best available techniques not entailing excessive costs" (BATNEEC) for the sector.
The new "amplification note" revising the Agency's process guidance on incineration states: "The economics of the animal incineration business have changed significantly since the original guidance note was written." The guidance does not apply to existing plants.
One incineration firm which has already constructed a new cattle cremator in Nottingham, the Yorkshire Water business WRE Services, says it will have to rebuild the plant in order to gain authorisation. The four chimneys will be replaced with a scrubber connected to a single stack, and the company will also need amendments to its planning consent.
"It's unfortunate it has taken so long for the guidance to be issued," commented WRE's Ian Bryan. "This guidance is diametrically opposed to the Government's procurement policy." The Intervention Board knew that the proposal did not include scrubbing when it awarded the contracts last year, he said. WRE will renegotiate its contracts to cover commissioning delays of at least three months and extra costs of about £0.5 million per site.
Meanwhile, Government negotiations with the electricity generators over burning MBM and tallow in coal-fired power stations appear to have reached stalemate. Agriculture Minister Jack Cunningham has accused them of demanding too high a price to burn the waste - more than 300,000 tonnes of which is now in store - and suggested that the Government may instead requisition a disused power station.
A Ministry of Agriculture spokesman said that all disposal options are still being considered for OTMS waste, including landfill. Landfilling was considered early in the BSE crisis but later thought not to comply with an EC Regulation requiring OTMS animals to be "incinerated or rendered and destroyed." The high costs of incineration and lack of available capacity may lead Ministers to reconsider the issue.
The Agency's newly published risk assessment concludes that all disposal routes, including landfill, pose negligible risk. The Agency's consultants, DNV Technica, examined landfills where 6,100 BSE-suspect carcases were buried up to 1991. They concluded that the risks from contaminating water supplies with BSE infectivity were not significant. With "conservative" assumptions, the risk of death for exposed individuals came out at less than one in 50 million, and "in reality would be closer to zero".
If landfilling whole carcases from BSE suspects poses negligible risks, then landfilling OTMS waste - which does not come from BSE suspects and has been treated by rendering - could also be justified in risk terms. There is also an inconsistency in controls on cattle waste in that MBM produced from specified bovine materials (SBM) from cattle aged under 30 months can be sent to landfill. This practice is likely to resume shortly, even though the material contains more BSE infectivity per tonne than OTMS waste.
In its assessment of power stations, the Agency concluded that the greatest risk from burning rendered cattle waste was through MBM spillages from material handling equipment. This pathway outweighed the risks from any residual infectivity in the power station ash. The most exposed individual would be a person drinking untreated surface water contaminated with effluent from the site, who would face a minute - one in 30,000 million - chance of infection.
For incinerators burning BSE-infected cattle, the risks are also dominated by pathways affected by spillage of infected material. The risks to individuals were calculated at less than one in 1,000 million.