LAQM: monitoring objectives
Part IV of the Environment Act 1995 implements Local Air Quality Management (LAQM). LAQM requires local authorities to provide an assessment - detailed, if deemed significant - of air quality impacts in their area. Nicholas Davey, Senior Consultant at Stanger Science & Environment (SSE), examines the impact on, and value to, industry.Under Local Air Quality Management (LAQM), local authorities have to consider the present and future quality of air and assess whether prescribed air quality objectives are likely to be achieved by specified deadlines. This involves a review of emissions from industry and other pollutant sources within a local authority's area. It is achieved by carrying out a three-stage process of emissions review and assessment, with each progressive stage requiring more detail than the one before. Stage 1 of the Local Air Quality Management (LAQM) process provides an initial screening of pollutant sources within an area. Emissions from both Part A and Part B industrial processes are assessed. Initially, the industrial processes within an area are screened on a checklist basis which identifies those that are potentially significant sources of specific pollutants. Where these processes are identified as "potentially significant", more detailed assessment is carried out at Stage 2, either through simple modelling or basic monitoring. Where Stage 2 indicates that exceedance of an air quality objective is likely, the local authority is required to undertake Stage 3 review and assessment, involving detailed modelling and monitoring. This assessment will accurately indicate the likelihood and extent of exceedance, so it is imperative that monitoring data supplied to local authorities is representative and up-to-date. Where exceedance is demonstrated by Stage 3, the local authority is required to designate an Air Quality Management Area (AQMA).
LAQM, however, has many benefits to industry and should be approached positively by all sectors. It provides an assessment of the air quality impacts of a process and, where identified as potentially significant, these are assessed in detail at no expense to the operator. Sophisticated atmospheric dispersion modelling and validation monitoring are usually relatively expensive exercises - often requested by government bodies. Although in some local authority areas the larger processes may be asked to contribute to the funding of the work, local authorities are under an obligation to carry out this work to the best of their financial means, regardless of funding from industry. However, where industry decides to contribute funding to these assessments, good PR is likely to result and demonstrates a forward thinking company. The review and assessment may also provide evidence to turn around a negative public perception, as was found with a large-scale air quality monitoring project in Barry, South Wales, which Stanger carried out over the period 1997-1999.
The Barry Industrial Complex (pictured above) lies approximately 10 miles west of Cardiff in South Wales. The companies located at the complex include AES, Blagden Cellobond, Cabot, Dow Chemical, Dow Corning, EVC, National Power, Inspec and Zeon. The pollutants monitored included the majority of those outlined in the National Air Quality Strategy plus many others. In total, 24 different pollutants where monitored which were based on the processes within the complex. These included both inorganic and organic pollutants plus different size fractions of particulate.
The results from the monitoring were found to be very encouraging and demonstrated that all pollutants set-out in the National Air Quality Strategy (NAQS) were below their respective criteria at all four sites when compared with the most recent air quality objectives. Other pollutants not covered by the NAQS were compared with Environmental Assessment Levels. Formaldehyde was the only pollutant that showed higher than expected concentrations, but further work revealed that these were comparable to those measured in Cardiff City Centre.
The monitoring programme has proven to the local community that air quality surrounding the site is not the hazard that was originally perceived. The joint funding of this programme between the industries within the Responsible Care Group and the Environment Agency has resulted in good PR for the companies at little cost. It has also provided re-assurance to the both the local residents and the companies involved that air quality impacts on the surrounding area are minimal.
"We are extremely encouraged by the results of the first year's report, says Andrew Littlewood, chairman of the Responsible Care Group. "As an industrial complex we are committed to working to the highest possible environmental standards. The Responsible Care Group very much hopes that the report will be welcomed by the local community as a positive sign that the complex is operating to very high standards."
SSE has also recently completed Stage 2 Review and Assessment of air quality on behalf of Newport County Borough Council. The area has more than 20 Part A processes within its boundaries, and some of these have been identified as potentially significant sources of nitrogen dioxide, sulphur dioxide and PM10 (particulate matter). More detailed assessment will shortly be carried out using similar methods to those used for the Barry monitoring programme in order to accurately assess the likelihood of achieving the air quality objectives for each of these pollutants. Stanger's work for the Newport air quality review and assessment has been selected by the DETR as an example of Best Practice.
There appears, however, to be significant disparity between companies in their willingness to supply data for the purposes of LAQM - it should be in their interest to assess the impacts of their activities in sensitive areas. Besides, LAQM offers the most cost-effective method of assessing air quality impacts.