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P recovery from wastewater treatment plants (WWTPs) as struvite fertiliser is a recognised method of improving P use efficiency and reducing P losses into the environment. The main driver for P recovery from the water industry viewpoint is the reduction in the nuisance of struvite clogging inside pumps and pipes. Struvite recovery leads to an average P recovery rate of 72 ± 7% from centrifuge centrate, with 8.8 ± 0.7% total P and 20.5 ± 3.2% PO 4 -P removed from the WWTP influent as struvite. This reduces the potential for struvite precipitation, moderates P loads on biological nutrient removal processes and lowers P concentration in the final effluent. Totalling revenue from sale of struvite and operational site savings, P recovery becomes an attractive option for water companies. The implementation of P recovery technologies to produce struvite fertiliser in all UK WWTPs could produce a national P fertiliser source of 7.05 ± 2.01 kt P/year. In addition, sludge produced at WWTPs could be diverted to advanced energy recovery (AER) processes and P recovered from AER residues; up to 21.71 ± 0.95 kt P/year could be recovered in this way in the UK. Combining the two methods of P recovery, UK imports of P fertiliser could be reduced by 36.2 ± 1.1%. P recovery on a large scale has the further benefit of protecting against eutrophication by reducing P emissions to water bodies by 21.7 ± 1.9%. The protection of the environment and reduction in reliance on imported P are major national motivations to legislate P recovery from waste. [ABSTRACT FROM AUTHOR]

Milà i Canals et al. (Int J Life Cycle Ass 14(1):28-42, ) referred to as ‘Part 1’ in this paper) showed that impacts associated with use of freshwater must be treated more rigorously than is usual in life cycle assessment (LCA), going beyond the conventional consideration only of ‘blue’ water (i.e. irrigation and other abstractions), and suggested an operational method to include the impacts on freshwater ecosystems (freshwater ecosystem impact) and abiotic resource depletion (freshwater depletion). The inclusion of water-related impacts in LCA is of paramount importance, particularly for agricultural systems due to their large water consumption worldwide. A case study of UK consumption of broccoli grown in the UK and Spain is presented here to illustrate the method suggested in Part 1. Water footprint (WF) and life cycle impact assessment (LCIA) methods presented in Part 1 are applied to six different and synchronic supply chains providing broccoli during the British colder months (November–April); four of these chains refer to broccoli produced in Spain and the other two are based on frozen British produce. In addition, four UK-based supply chains delivering fresh broccoli from April to November are studied to provide a year-round perspective. Using WF accounting methods helps to provide a richer picture of the total water consumption associated with growing broccoli. Including the volumes of water consumed in the life cycle inventory (LCI), assessed following the WF approach (evaporative uses of irrigation water and soil moisture), shows that the total water consumption does not vary greatly between UK and Spanish broccoli production. However, when impact assessment indicators based on the water use per resource ratio are applied, water use in Spain is shown to be much more critical, with significantly higher impact for Spanish cultivation. While the largest component of water use in Spain is linked to irrigation, the study reveals other important uses in the life cycle of vegetables, namely direct use of water for cooking and sanitation, land use effects on the water cycle and electricity production. The results highlight the importance of distinguishing between different water volumes and sources in the different LCA phases: LCI (with and without full WF consideration) and LCIA. Traditional LCI results may be misleading when comparing irrigated systems in regions with differing water scarcity. The WF estimates are more relevant for sourcing strategies, as they show the total water requirements of crops including both irrigation water use as well as the use of green water (effective rainfall stored as soil moisture). Finally, LCIA results show the potential impacts of water consumption on freshwater ecosystems and future freshwater availability. This methodological framework improves the representation of impacts associated with water use in LCA. This helps in identifying the hotspots of the production system in terms of potential impacts to freshwater ecosystems, as well as in identifying where investments for water-saving may have the greatest benefit. In addition, this approach addresses a regional specific issue, water scarcity, which may often be closer to critical thresholds than other environmental impacts. The method should be tested with further case studies in order to confirm the suitability and necessity of the LCI modelling requirements and LCIA characterisation factors such as the explicit inclusion of evaporative water losses. The WF approach can benefit from experience of systems analysis gained in LCA, while LCA may benefit from the detailed accounting framework embodied in the WF approach, as illustrated in this paper. Because the purposes of the two tools are different, they will continue to evolve separately, but complementarity in application should guide this development. [ABSTRACT FROM AUTHOR]

Background, aim and scope Considerable debate surrounds the assessment of the environmental impacts and the ethical justification for providing a year-round supply of fresh produce to consumers in the developed countries of northern Europe. Society is seeking environmentally sustainable supply chains which maintain the variety of fresh food on offer throughout the year. This paper compares the environmental impacts of different supply chains providing lettuce all year round to the UK and considers consumers' meanings of--and attitudes to--available options. Lettuce has been selected as a case study as its consumption has grown steadily during the last two decades and the supply chains through cold months are protected cropping in the UK and field cropping in Spain; during warm months, lettuce is sourced from field cropping in the UK. Materials and methods Data were collected from farms supplying each of these supply chains, and life cycle assessment methodology was used to analyse a range of impacts associated with producing (from plant propagation to harvesting and post-harvest cooling) and delivering 1 kg of lettuce to a UK Regional Distribution Centre (RDC). The downstream stages (i.e. retailing, consumption and waste management) are the same regardless of the origin of the product and were omitted from the comparison. The impacts considered included potential to induce global warming and acidification as well as three inventory indicators primary energy use, land use and water use). Qualitative data were collected in order to assess the consumer considerations of purchasing lettuce also during winter. Results Importation of Spanish field-grown lettuce into the UK during winter produced fewer greenhouse gas (GHG) emissions than lettuce produced in UK-protected systems at that time (0.4-0.5 vs. 1.5-3.7 kg CO2-eq/kg lettuce in RDC). Refrigerated transport to the UK was an important element of the global warming potential associated with Spanish lettuce (42.5% of emissions), whilst energy for heating dominated the results in UK-protected cultivation (84.3% of emissions). Results for acidification were more variable and no overall trends are apparent. Results from qualitative social analysis revealed complex and multidimensional meanings of freshness and suggested that the most striking seasonal variation in vegetable/salad eating was a tendency to consume more salads in the summer and more cooked vegetables in the winter, thus suggesting that in-home consumption alone cannot explain the rise in winter imports of lettuce to the UK.… [ABSTRACT FROM AUTHOR]

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http://dx.doi.org/10.1065/lca2006.04.009 logy. This paper describes a case study carried out as part of a wider programme to provide support for environmental decision-making in the highway maintenance programme of a local government body: Surrey County Council (SCC). UK local authorities are required to demonstrate that sustainable development principles are addressed in service provision, by improving environmental, economic or social wellbeing and improving public consultation. A methodological approach was developed to meet these requirements by using life cycle assessment (LCA) and multi-criteria decision analysis (MCDA) through the process of decision conferencing. In projects requiring strategic decisions, difficulties arise in identifying relevant sustainable development criteria and in evaluating maintenance options against these criteria where the context for decision-making is complex and characterised by uncertainty, where multiple public policy objectives compete and a number of decision-makers and key players are affected by the outcome. Clearly, a structured process is needed to engage such stakeholders in the decision process, utilising quantitative and qualitative information. The approach described proved to be capable of fulfilling these requirements. and Recommendations. The approach of combining LCA with MCDA through decision conferencing is capable of further development to support other strategic decision-making activities. However, this illustrative case study has revealed a need for methodological developments in LCA for local, project-level decisions. [ABSTRACT FROM AUTHOR]

Comments on the spread of animal diseases which affected British livestock farming. Information on how mad cow disease was spread; Details on the spread of foot-and-mouth disease; Advice on how to avoid contamination.