An evidence based approach to predicting the future supply of aggregate resources in England

Lusty, P.A.J.; Bee, E.J.; Bate, R.; Thompson, A.; Bide, T.; Morigi, A.; Harris, K.. 2011 An evidence based approach to predicting the future supply of aggregate resources in England. British Geological Survey, 205pp. (OR/11/008) (Unpublished)

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Securing continuity in the supply of aggregate minerals for the construction industry is a major objective of minerals planning policy and practice in Minerals Policy Statement 1: Planning and Minerals (MPS1) (DCLG, 2006). At the same time, there are numerous constraints on where minerals can best be obtained, led by geological availability and tight restrictions in protected areas. Over time, areas suitable for quarrying are worked out or encounter insurmountable obstacles to further operations, and new arrangements must be made. This research study sheds light on this process by tracking the supply of construction aggregates from existing sites; highlighting where and why supply problems can be expected to arise in the future; and suggesting ways of easing the transition where continuity of supply could be at risk. Identifying land for future quarrying, and securing extraction, is a complex balance between markets, constraints, positive planning objectives and practicalities. This study illustrates competing issues and describes how they have been resolved, or otherwise, in strategic planning terms. Tensions in the aggregates supply pattern reinforce the need for a clear and equitable approach to deciding where aggregates working should take place and on what scale. The areas with greatest demands – the conurbations – are not the places where sufficient quarrying can readily be accommodated. Indeed whole counties and regions may be deficient in certain mineral types, and must import from elsewhere to meet their needs. Resource-rich areas need to be convinced that their exports to areas of greater demand or worse resource deficiency are sufficiently necessary to justify the environmental impact of working. At the same time, the locations where mineral companies are prepared to invest are strongly affected by the quality of mineral resources available, transportation to markets, and by the actions of competitors. The starting point for the study is an evidence based analysis of the likely pattern of aggregates supply from planning permissions for quarrying which already exist. The most widely used indicator to the life-expectancy of these ‘permitted reserves’ is the landbank in an area, expressed in years. This equates to the number of tonnes of permitted reserves in operational and inactive sites (but not in statutorily dormant sites) divided by the annual rate of supply. Landbanks have a number of limitations, not least averaging out the circumstances at individual quarries so that the ability of individual companies to contribute to mineral supply can be unclear or even misleading. A key output of this analysis is a more accurate understanding of when individual sites will cease production (due either to their planning permissions expiring or their reserves being worked out) within a broad context of reserves with planning permission across an MPA area. This gives a clear indication of when and where alternative arrangements need to be made to ensure continuity of aggregates supply. The study resolves this by the use of rundown charts. These collate information from individual quarries across an area, usually a Mineral Planning Authority (MPA). They are column charts showing from one year to the next first for reserves and second for annual supply how the industry is likely to operate using existing permissions. As the reserves are used up, both charts show steps downwards in reserves and supplies. Most data for the study are based on 2007, to identify likely rundown patterns at pre-recession rates of supply. The effect of the recession will be to enable permitted reserves to last longer. Rundown charts are presented for numerous authorities and for different mineral types around England, showing how successful this method is at highlighting critical dates when shortfalls in supply can be expected. They can also help indicate the cause of the shortfalls. They illuminate the role of the productive capacity of processing plant, the contribution of inactive sites (whether brought back into use or remaining inactive), and the impact of the universal end-date of 2042 imposed on old mineral permissions which did not have their own specified end date. Many MPAs have more parlous supply positions than expected by government policy, particularly for sand and gravel, and by far the most important foreseeable shortfall in the medium- to long-term is amongst the four rail-connected igneous quarries in Leicestershire producing around 15 Mt of crushed rock between them in 2007. The most common and practical response to an emerging shortfall in the supply of an aggregate mineral is the allocation of new land for quarrying and the granting of additional permissions in the area. However, this may not always be a practical solution to the demand problem for reasons set out in the study. For example, these include: • limited reserves remaining to exploit; • MPAs may consider the constraints on further working to be over-riding; or • mineral companies may not wish to develop the areas proposed by the MPA. In these circumstances there may be a need to identify alternative supply arrangements, but the study found that this approach could also encounter obstacles. Not only is there resistance from the areas proposed for new or additional workings, but effective channels for resolving issues across regional boundaries do not exist. Addressing problems foreseeable within the next ten years is problematic enough, and very little attention is being paid to problems expected in the medium-term (2020 onwards) or beyond. Consultations with a wide range of interested parties suggested that the issues most affecting continuity of supply could be broadly divided between three themes: uncertainty in the planning and investment process, environmental constraints, and adequacy of geological information to support planning for mineral supply. The forward planning system exists to provide a measure of certainty for all parties about the type and location of development likely to be permitted. The study confirms previous work, showing that inadequacies in plan-making are discouraging aggregates proposals from coming forward. Some plans are out of date; others are not being prepared quickly enough; and changes to the planning system have created a hiatus in the preparation of some plans. MPAs also face increasing difficulties in assembling data to monitor the big picture for aggregates planning, as data is increasingly held back on confidentiality grounds (either by MPAs or mineral companies). Nonetheless, examples of good practice in long-term forward planning for minerals demonstrate what is possible, whether through co-operation between an MPA and a company, or between groups of companies and MPAs across authority boundaries. Consideration of environmental issues focuses initially on the impact of nationally important landscapes and wildlife sites. As might be expected aggregates working has been resisted in these areas, though the study identified exceptions. There is debate over the weight to afford locally designated landscapes. This is in contrast to nationally designated areas for which clear government policy exists. The impact of wildlife designations appears to be of limited significance for national supply, though with important exceptions identified. These include nationally important igneous rock quarries in Leicestershire and limestone quarries in the east Mendips of Somerset. Wildlife designations can nonetheless be important in influencing aggregates planning at a local level, for example sand and gravel working in Cheshire. The level of geological data required for planning for mineral supply varies considerably depending on the intended purpose. The adequacy of the geological database required to support long-term planning for mineral supply is variable across the country. Existing data provision, principally British Geological Survey (BGS) Mineral Resource Maps, are generally considered adequate for strategic level planning for mineral supply. Geological data which can prove indicated resources, specifically mineral quality and volume, is considered vital for the delineation of preferred areas and specific sites. The data currently available from BGS, with the exception of some areas covered by more detailed surveys, is generally insufficiently detailed for this purpose. Specially commissioned studies and mineral company information frequently supplement the national resource information. Some consultees suggested that a degree of reliance on operators for mineral resource information in some areas can result in a bias towards industry’s ‘preferred areas’. Confidentiality may also be a limitation to the use of industry data and illustrates the continued need for independently sourced and compiled resource information. Furthermore, the growing shortage of minerals planning expertise in local authorities may increasingly limit the appropriate utilisation of geological information. It is not practical to have more detailed mineral resource information in all parts of the country. However, a targeted approach to data acquisition is required in areas where significant constraints on supply are demonstrated and clear deficiencies in the evidence base occur. This is particularly important for nationally significant resource areas such as Leciestershire. As a result of this assessment of aggregate resources, working sites and constraints, a number of supply issues have been identified. These include some major considerations, such as replacing the output from the Leicestershire igneous rock quarries and limestone from the Peak District National Park, and more localised issues such as alternative sand and gravel supply options in the West Midlands. These not only illustrate a range of problems but the need for appropriate procedures for addressing them. Any change in supply pattern required to compensate for reduced output from a constrained resource area will have environmental, social and economic implications. In no case is there a simple solution, but in all cases there is a clear requirement for a proper debate and prompt decision-making to avoid continuity of aggregates supply being put at risk.

Item Type: Publication - Report
Programmes: BGS Programmes 2010 > Minerals and waste
Funders/Sponsors: Minerals Industry Research Organisation (MIRO)
Additional Information. Not used in RCUK Gateway to Research.: This item has been internally reviewed but not externally peer-reviewed
NORA Subject Terms: Earth Sciences
Date made live: 21 Jun 2011 11:27 +0 (UTC)

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