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Contaminated sites are receiving increasing policy attention internationally due to the significant threats they pose to eco-environmental and human health. In China, a range of policies for contaminated site management have been developed and implemented with the ambition of reaching "zero contaminated sites" – in particular using a policy-driven approach to remediate or manage site risk while delivering useful synergies between services and opportunities in site reuse. To examine the interaction between policy making, policy implementation, and policy outcome, we designed a three-dimensional conceptual model of policy evaluation, and established an indicator framework of stakeholder perceptions covering policy formulation, policy implementation and policy outcome, which was tested in five cities in China (Chengdu, Beijing, Changsha, Chongqing and Shanghai) through interviews with various stakeholders. A combined method of fuzzy synthetic evaluation and entropy weight was applied for the purpose of quantification and comparability of evaluation results at different levels. The results show that: (1) there is no inevitable causality between policy formulation, policy implementation and policy outcome. Policy formulation, which is the premise of policy implementation and may largely influence policy outcome, does not perform well in all tested cities. Policy implementation is the key step and contributes most to the performance of the whole policy process. (2) In general, Chongqing and Beijing have a less-than-ideal performance compared to the other three study cities in contaminated site management. Due to differences in regional context, the same measure may produce different policy outcomes in different cities, indicating a need to carry out specific, locally contextualized or calibrated policies, based on the local cultural and socioeconomic environment. (3) The fuzzy synthetic evaluation method proved feasible in the quantitative evaluation of environmental policy, and can help to (i) better understand the advantages and challenges of implementing contaminated site management policy in target cities, and (ii) provide evidence for further decision making.

Abstract. Geological identification of tsunami deposits is important for tsunami hazard studies, especially in areas where the historical data set is limited or absent. Evidence left by historical tsunamis in the coastal sedimentary record of the Gulf of Corinth was investigated by trenching and coring in Kirra on the north coast and Aliki on the south coast. The Gulf of Corinth has a documented tsunami history dating back to the 4th century BC. Comparison of the historical records and the results of stratigraphical, sedimentological and foraminiferal analyses show that extreme coastal flooding events are detectable in the coastal sequences. The geological record from Kirra shows four sand layers deposited by high-energy marine flooding events. The deposits identified show many similarities with tsunami deposits described elsewhere. The lower sand deposit (layer 4) was radiocarbon dated to 3020–2820 BC. Assuming an average sedimentation rate of 2.6 cm (100 yr)−1, the ages of the other three sand layers were estimated by extrapolation to the time windows 1200–1000 BC, AD 500–600 and AD 1400–1500. There are no historical tsunamis which correlate with layers 2 and 3. However, layer 1 may represent the major AD 1402 tsunami. Sand dykes penetrating from layer 1 into the overlying silts suggest soil liquefaction during an earthquake event, possibly the 1 August 1870 one. At Aliki, no clear stratigraphical evidence of tsunami flooding was found, but results from foraminiferal and dating analyses show that a sand layer was deposited about 180 years ago from a marine flooding event. This layer may be associated with the historical tsunami of 23 August 1817, which caused widespread destruction in the Aegion area. The work presented here supports the idea that geological methods can be used to extend tsunami history far beyond the historical record. Although the tsunami database obtained will be incomplete and biased towards larger events, it will still be useful for extreme event statistical approaches.

Many previous studies have shown that measurements of Pb isotopic compositions provide a powerful tool in determining the origin of Pb in a wide range of environments. In the present study, this method was applied to airborne particulate matter sampled in urban areas from two countries: France and the United Kingdom. Initially, the main potential sources of Pb contamination were defined isotopically. Three important end-members contribute to urban Pb load: the Pb added as an anti-knock agent in gasoline (defined by ²⁰⁶Pb/²⁰⁷Pb ≈ 1.061-1.094), industrially-derived Pb (²⁰⁶Pb/²⁰⁷Pb ratios ≈ 1.143-1.155) and « natural/local » Pb (derived from rocks and soils, ²⁰⁶Pb/²⁰⁷Pb ≈ 1.17-1.20). Urban airborne particulate matter, sampled only a few metres from dense car traffic, yields a wide range of ²⁰⁶Pb/²⁰⁷Pb values (1.085 - 1.158), which do not fall entirely within the gasoline domain. As a consequence of recent environmental legislation and increased use of unleaded gasoline, emission of car-derived Pb has been drastically reduced and today, other sources of Pb are important contributors to total Pb, even in urban environments. In addition, this study demonstrates that the contribution of each end-member can vary considerably over the short-term as a Junction of car traffic density and wind direction. ; On sait depuis longtemps déjà que les isotopes du Pb peuvent être utilisés avec succès pour déterminer l'origine du Pb dans presque tous les écosystèmes. Ici, cette méthode a été appliquée à l'étude des aérosols urbains dans quelques villes françaises et anglaises. La première étape a été de définir isotopiquement les principales sources de Pb. II apparait trois grands groupes: le Pb ajouté comme anti-détonant dans les essences, qui présente des rapports ²⁰⁶Pb/²⁰⁷Pb ≈ 1.061-1.094, le Pb émis plus généralement par l'activité industrielle avec des ²⁰⁶Pb/²⁰⁷Pb ≈ 1.143-1.155 et le Pb naturellement présent dans les roches et les sols qui montre des valeurs sensiblement plus élevées ≈ 1.17-1.20. Les compositions isotopiques mesurées dans les aérosols urbains, prélevés à seulement quelques mètres d'un intense trafic automobile, montrent une large gamme de variation : 1.085 - 1.158, qui ne reflète pas pleinement la signature observée dans Les essences, comme on aurait pu s'y attendre à priori. Au contraire, à la suite des mesures visant a réduire les émissions de Pb liées aux automobiles, d'autres sources (qu'elles soient industrielles et/ou naturelles) peuvent être identifiées aujourd'hui, même dans un environnement urbain. De plus, cette étude démontre que la proportion de chaque composant peut considérablement varier suivant Les conditions de trafic ou la direction des vents.

Addressing food security issues arising from phosphorus (P) scarcity is described as one of the greatest global challenges of the 21st Century. Dependence on inorganic phosphate fertilisers derived from limited geological sources of P creates an urgent need to recover P from wastes and treated waters, in safe forms that are also effective agriculturally – the established process of P removal by chemical precipitation using Fe or Al salts, is effective for P removal but leads to residues with limited bioavailability and contamination concerns. One of the greatest opportunities for P recovery is at wastewater treatment plants (WWTPs) where the crystallisation of struvite and Ca-P from enhanced biological P removal (EBPR) sludge is well developed and already shown to be economically and operationally feasible in some WWTPs. However, recovery through this approach can be limited to <25% efficiency unless chemical extraction is applied. Thermochemical treatment of sludge ash produces detoxified residues that are currently utilised by the fertiliser industry; wet chemical extraction can be economically feasible in recovering P and other by-products. The bioavailability of recovered P depends on soil pH as well as the P-rich material in question. Struvite is a superior recovered P product in terms of plant availability, while use of Ca-P and thermochemically treated sewage sludge ash is limited to acidic soils. These technologies, in addition to others less developed, will be commercially pushed forward by revised fertiliser legislation and foreseeable legislative limits for WWTPs to achieve discharges of <1 mg P/L.