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This paper presents the preliminary results of field trials conducted to investigate the air permeability of waste at the Braambergen landfill located near the city of Almere, the Netherlands. Pressure variations were monitored in surrounding wells during air extraction tests using differential pressure transducers. The magnitude of the pressure response to gas abstraction indicates suitability of the method to investigate waste permeability and the swiftness of the pressure response indicated good connectivity within the investigated well field. The obtained air permeability values showed a trend where permeability decreased as the distance between two wells increased, suggesting higher permeability in closer proximity to a well. Although the values are comparable to those reported in other landfills, the differences can be explained by the influence of site-specific factors on permeability., Green Open Access added to TU Delft Institutional Repository ‘You share, we take care!’ – Taverne project https://www.openaccess.nl/en/you-share-we-take-care Otherwise as indicated in the copyright section: the publisher is the copyright holder of this work and the author uses the Dutch legislation to make this work public., Geo-engineering

The recirculation and infiltration of leachate in landfills may be carried out to facilitate the flushing of contaminants and accelerate the stabilisation of waste. Flushing contaminants through recirculation relies on the movement of fluids through the landfill body to basal drains, which will predominantly be driven by gravity. Leachate recirculation and infiltration measures commenced at de Kragge II landfill (Bergen op Zoom, The Netherlands) in March 2018. Up to 90 m3/day of treated leachate is recirculated into the top of a 20 m deep, 5 ha landfill cell through 14 horizontal drains installed at the surface. Poor connectivity between the waste and the basal drainage system has resulted in saturated conditions forming in the lower 7-8 m of the landfill. Knowledge about the leachate flow within the waste body is essential for evaluating the success of the stabilisation measures. To investigate the flow regime within the saturated waste, 22 Single Borehole Dilution tests were carried out in 13 piezometers at different depths, between 8.4 and 18.1 m below ground level, and locations across the landfill cell. Tests were repeated in a number of the piezometers to demonstrate repeatability. Flow was measured in all piezometers. Calculated Darcy flow velocities ranged between 0.01 and 1.02 m/day, with the highest velocities measured in the deepest piezometers. Four tests were carried out in one nest of piezometers installed at different depths, with the leachate recirculation system switched off for two days prior to and during the test. Although flows were somewhat higher in two of the piezometers, it was not possible to conclude whether the infiltration of leachate significantly influences flow., Green Open Access added to TU Delft Institutional Repository ‘You share, we take care!’ – Taverne project https://www.openaccess.nl/en/you-share-we-take-care Otherwise as indicated in the copyright section: the publisher is the copyright holder of this work and the author uses the Dutch legislation to make this work public., Geo-engineering

Within the framework of the Dutch sustainable landfill project iDS, four compartments of the Dutch landfill Braambergen have been treated by in-situ aeration since 2017. The aeration infrastructure comprises 230 wells with a spacing of 15 to 20 m, distrib-uted over an area of around 10 ha, intercepting a waste body of 1.2 × 106 t of contam-inated soils, soil treatment residues, bottom ashes and construction and demolition waste. The wells, used in an alternating fashion for air injection and gas extraction, can also be used to monitor water tables within the waste body. In order to describe the spatial variability of waste hydraulics, design a larger scale leachate pumping test and, eventually, support model predictions of the site’s water balance and emission potential, analyses of leachate composition and pumping tests on individual wells have been conducted. The spatial variability of leachate quality and water tables is very high with no geospatial relationship between the sampling points. Each sampling point is representative of itself only. Large differences prevail not only between and across the compartments, but also between directly neighbouring wells. Both the small scale differences in leachate tables as well as in leachate quality indicate a spatial pattern of zones with low horizontal connectivity within the waste body. Recovery rates of drawdown in the wells yielded preliminary estimates of horizontal waste hydraulic conductivity in the order of 1×10-7 to 6×10-4 m/s., Geo-engineering

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Full Text, Thesis (PhD Doctorate), Doctor of Philosophy (PhD), School of Govt & Int Relations, Griffith Business School, This thesis seeks to advance understandings of why states’ foreign policy decisions vary when the material and social conditions underpinning their interests have not changed. It focuses on American foreign policy, and specifically on US decisions on whether to use military force abroad. It works to show that variation in these types of decisions can best be explained through an emphasis on the different types of ideas that emerge in debates within presidential administrations, rather than through adopting rationalist approaches making generalised presumptions of state self-interest. Since the end of the Cold War, the US has remained a great power and enjoyed relative stability in coalitional alignments. Despite this relative stability in material and relational conditions, however, decisions to use military force abroad have varied considerably across cases, including in humanitarian crises in the Balkans in the early 1990s, the War on Terror from 2001, and more recent conflicts in Libya and Syria. But what explains this variation? Existing rationalist theoretical approaches in International Relations have often pointed to crises and “exogenous shocks” to explain variation in foreign policy interests. In doing so, they have emphasised rational self-interest, presuming that agents use information efficiently in efforts to pursue either material or ideational bases of state interests. Yet, realist, liberal, and constructivist scholars have struggled to explain variation in state interests in the absence of either a change in the international distribution of material capabilities or in the face of ideational change. For example, in regard to possible intervention in Bosnia in the early 1990s, President George H.W. Bush urged restraint, arguing that the conflict was fuelled by “ancient, ethnic animosities”, and that the US “did not have a dog in the fight”. His successor, Bill Clinton, initially adopted the same approach. Yet, following the massacre at Srebrenica in 1