Agency promises tougher line in cement kiln response

Last autumn, the Agency conducted what Dr Slater describes as "probably the most extensive local air pollution survey ever carried out" in Britain in the vicinity of the works.

Ambient levels of sulphur dioxide and fine particulates (PM₁₀) were continuously measured at eight sites over an eight-week period. An intensive two-week campaign involved plume tracking with differential absorption lidar, mobile laboratories and investigation of public complaints to a telephone hotline. Monitoring of emissions from Castle Cement's site and the nearby ICI Katalco and Tarmac works was also carried out.

The £500,000 study found that air quality in the area was "generally very good, and the number of exceedances was not unusually high."³ The highest levels of SO₂ were found in the village of Chatburn to the east of the cement works, where the Government's proposed air quality standard for SO₂ was exceeded on just two occasions. PM₁₀ levels were highest in the town of Clitheroe - linked mainly to vehicle emissions and bonfire night celebrations.

However, 29 telephone complaints relating to current incidents were received during the two-week campaign. The Agency says that reports of odour and health problems correlated strongly with elevated SO₂ levels but not with the use of SLF. Castle Cement was the main source of SO₂ at ground level, although Tarmac's site may also have a significant impact.

The Agency says that SO₂ levels are too low to explain the odour or health effects which have been reported even by its own contractors (ENDS Report 252, pp 12-13 ). It concludes that some other pollutant may be to blame, and now plans to analyse grab samples of the grounded plumes.

Castle is due to commission a scrubber on its wet kiln in January (ENDS Report 256, pp 6-7 ). The Agency has varied the firm's authorisation to forbid persistent haze or offensive odour to be present at ground level beyond the site boundary after March 1998. But the Agency's survey suggests that the plume from the dry kilns, which use SLF, may contribute to the problems - suggesting that Castle may fail to comply with the new condition.

The Agency prosecuted Castle last year for a spillage of SLF (ENDS Report 262, p 45 ) and intends to prosecute it again for breaches of IPC emission limits. The response reveals that another prosecution has been initiated against the company for an unconsented discharge to the river Ribble.

In June, Castle was also served with an enforcement notice following complaints of dust emissions from its Padeswood site in North Wales. The company had failed to keep plant in good working order, to notify the Agency that an abatement plant was not in operation, and to control particulate releases during handling and storage of materials.

The Agency maintains that it "is interested in proposals to burn substitute fuels in cement kilns, provided the environment is not adversely affected." But it has agreed to strengthen the protocol with more prescriptive monitoring and data handling requirements in order to lessen "misunderstanding and suspicion." A revised protocol will be sent out for consultation and is due to be in place by the end of the year.

The Agency also plans to reconvene its Substitute Fuels Trials Assessment Panel, set up in early 1995 to assess applications to burn SLF but since disbanded. The panel found "inconsistencies, errors and assumptions" in several applications, the Agency says, and carried out separate assessments to verify the operators' conclusions.

The Committee urged the Agency to adopt a "more rigorous and consistent approach" to its BPEO assessment methodology. The Agency refutes claims that it has manipulated data, and says it conducted sensitivity analyses and worst case scenarios to address shifts in "environmental assessment levels". It has been "robustly challenging" Blue Circle's BPEO assessment for the Weardale works (ENDS Report 268, pp 6-8 ) - though this tougher line came after the Committee's inquiry.

The Agency proposes increased public consultation over applications to burn waste fuels - and in general where changes to any IPC process is "likely to be of concern to the public."

Most applications to burn substitute fuels need a "substantial change" to the authorisation, the Agency says. However, it will ensure full consultation even when the change is not substantial, when it will bear the cost of advertising in newspapers. It will also explore advertising on local radio and public notices to raise awareness of any proposed trial.

Inspectors will prepare a summary consultation document on each proposal for a new trial or continued use of substitute fuels, and place decision documents on the register.

The Committee concluded that burning wastes of high calorific value (CV) was a recovery operation - but that use of low-CV wastes was disposal, which could in theory be viewed as a change of use for planning purposes. A blend of both types of waste was, it said, a mixture of disposal and recovery.

The Government disagrees, saying that a waste management operation "cannot simultaneously be both" disposal and recovery and that the definition of the activity must depend on the facts of the case. This approach fails to address the Committee's concern that fuel suppliers may seek to dispose of wastes by blending them with high-CV streams to make SLF.

However, the Agency suggests that the minimum CV of 21,000kJ/kg which it has set for substitute fuels will "ensure that the addition of waste streams to the blend which do not contribute to the performance of the fuel is minimised." The Agency therefore concludes that the use of such fuels constitutes energy recovery rather than disposal.

Even so, the Government declined the Committee's request for a clear view on how the material change of use test for planning purposes should be applied to the use of alternative fuels in industrial processes. It notes that the matter will shortly be tested in the courts by judicial review, and will review the need for clarification in light of that ruling.

The Government's response skirts the issue, noting merely that the existing BPEO assessment methodology gives weight to transboundary and global effects. However, this misses the point that the methodology looks solely at process emissions and excludes impacts from raw material selection, transport, off-site power generation and waste disposal.

In April, the Agency suggested that it was developing plans to address these impacts under a "wider BPEO" assessment (ENDS Report 267, pp 32-33 ). It has now stepped back, apparently in the light of legal advice that its wider environmental duties are subordinate to its duties under IPC.

The Agency now says that even if it was "satisfied that, for example, the wider BPEO for the disposal of a certain [waste fuel] was in fact incineration, it could, nevertheless, not lawfully prevent its use in a particular cement plant, provided this was BATNEEC for that process."

However, both the Agency and the Government suggest that any deficiencies in the Agency's powers may be relatively short-lived. The 1996 EC Directive on integrated pollution prevention and control, due to be implemented in October 1999, requires consideration of indirect releases, consumption of raw materials and waste disposal.

In the meantime, the Agency has agreed to the Committee's call for research into the impact of the SLF programme on "closed loop" solvent recovery. It will also investigate the source and types of wastes and alternative disposal routes.

The Committee also called on the Government to draw up lists of low-CV wastes and hazardous materials which should be excluded from SLF - with the aim of safeguarding high-temperature incinerators. The Government rejects the move on the grounds that "it would not be appropriate to exercise control over the choices available to individual waste producers purely in order to protect one sector of the waste management industry from competitive pressures."

For its part, the Agency says it will consider the case for excluding waste streams when it revises the Bedford protocol.