Multiscale structure of UXO site characterization: spatial estimation and uncertainty quantification

Unexploded ordnance (UXO) site characterization must consider both how the contamination is generated and how we observe that contamination. Within the generation and observation processes, dependence structures can be exploited at multiple scales. We describe a conceptual site characterization process, the dependence structures available at several scales, and consider their statistical estimation aspects. It is evident that most of the statistical methods that are needed to address the estimation problems are known but their application-specific implementation may not be available. We demonstrate estimation at one scale and propose a representation for site contamination intensity that takes full account of uncertainty, is flexible enough to answer regulatory requirements, and is a practical tool for managing detailed spatial site characterization and remediation. The representation is based on point process spatial estimation methods that require modern computational resources for practical application. These methods have provisions for including prior and covariate information.     

Photochemischer und photokatalytischer Abbau von Carbamazepin,Clofibrinsäure,Iomeprol und Iopromid

Photochemical and Photocatalytic Degradation of Carbamazepine, Clofibric Acid, Iomeprol and Iopromide     

Plume and lithologic profiling with surface resistivity and seismic tomography

Improved surface-based geophysical technologies that are commercially available provide a new level of detail that can be used to guide ground water remediation. Surface-based multielectrode resistivity methods and tomographic seismic refraction techniques were used to image to a depth of approximately 30 m below the surface at the Natural and Accelerated Bioremediation Research Field Research Center. The U.S. Department of Energy (DOE) established the research center on the DOE Oak Ridge Reservation in Oak Ridge, Tennessee, to conduct in situ field-scale studies on bioremediation of metals and radionuclides. Bioremediation studies are being conducted on the saprolite, shale bedrock, and ground water at the site that have been contaminated with nitrate, uranium, technetium, tetrachloroethylene, and other contaminants (U.S. DOE 1997). Geophysical methods were effective in imaging the high-ionic strength plume and in defining the transition zone between saprolite and bedrock zones that appears to have a significant influence on contaminant transport. The geophysical data were used to help select the location and depth of investigation for field research plots. Drilling, borehole geophysics, and ground water sampling were used to verify the surface geophysical studies.     

Adapting rail and road networks to weather extremes: case studies for southern Germany and Austria

The assessment of the current impacts of extreme weather conditions on transport systems reveals high costs in specific locations. Prominent examples for Europe are the economic consequences of the harsh winter periods 2009/2010 and 2010/2011 and the floods in Austria, Eastern Europe, Germany and the United Kingdom in 2005 and 2007. Departing from the EC-funded project WEATHER, this paper delves into the subject of adaptation strategies by revisiting the project’s general findings on adaptation strategies and by adding two specific cases: (1) advanced winter maintenance on roads in southwest Germany and (2) technical and organizational measures in Alpine rail transport. For these two cases, feasible adaptation strategies are elaborated and their potential is discussed in light of damage cost forecasts up to 2050. For the road sector, we find a high potential to mitigate weather-related costs, although damages here are expected to decline. In contrast, rail systems face strongly increasing damages and the mitigation options offered by improved information and communication systems seem to be largely exploited. Consequently, it is easier to justify expensive adaptation measures for high-cost rail infrastructures than for road transport. A generic analysis of 14 damage cases worldwide, however, revealed that generally awareness raising, cooperation and communication strategies are sufficient to mitigate the most severe damages by natural disasters.     

Parameterization of subsurface heating for soil and concrete using net radiation data

The variability of surface sensible heat flux depends strongly on the heating rate of the material beneath the surface. This variability is expected to be large in urban areas where the surfaces are layered with a variety of man-made materials. Parameterization of the ground heat storage as a function of surface materials is presented based on analyses of data obtained during the U.S. Environmental Protection Agency's Regional Air Pollution Study conducted in St. Louis, Missouri. Ground heat flux data are derived from observations of surface and subsurface temperatures for a soil layer and for concrete slabs resting on soil. The data show that the presence of the concrete slabs increases the ground storage term relative to that for soil alone. The ground storage and sensible heat flux terms for a blackened concrete slab are larger than for an unpainted concrete slab. For the concrete surfaces, the ratio of ground storage to net radiation is >1 at night and <1 during the day. This ratio is discontinuous at sunrise and sunset transition periods. For soil, the ratio shows similar temporal behavior except that on average, there is a smoother transition at sunrise. Simple mathematical expressions giving the ratio of ground heat storage to net radiation as a function of time are presented.Now with Enviroplan, Incorporated, West Orange, NJ 07052, U.S.A.On assignment from the National Oceanic and Atmospheric Administration, U.S. Department of Commerce.     

Large and small numbers: options for quantifying the costs of extremes on transport now and in 40 years

The past 15 years has been characterized by a high density of record-breaking weather extremes in Europe. These include the extratropical cyclones Lothar, Kyrill and Xynthia across western and mid Europe; the major floods in the UK, Germany and eastern Europe; the heat waves in 2003 and 2007 and, after a long period of mild winters, the heavy winter seasons in 2009/2010 and 2010/2011. Inspired by the rising trends in weather-related damages worldwide and the studies on the topic carried out in overseas, the EC funded the sister projects such as Weather Extremes-Assessing the Impacts on Transport and Hazards for European Regions (WEATHER), EWENT and ECCONET to determine the magnitude of current and future risks to the European transport sector and to assess suitable adaptation strategies. This paper presents the assessment framework of the WEATHER project and the results of weather-inflicted damage costs now and in 2040–2050. Total annual damages are found to be around €2.5 billion, which largely attribute to road traffic. However, broken down to passenger and ton kilometers the highest risk is borne by rail traffic due to its expensive infrastructures and its comparably complex operating structure. This indication even amplifies when looking four decades ahead: while average road transport costs will only raise by 7 % due to milder winters, rail traffic costs may increase by up to 80 % due to more floods and less predictable winter periods. A comparison with the results of the EWENT study uncovers a high range of uncertainty concerning methodological approaches and data treatment. Thus, the final figures might even be much higher.     

Development of Easy and Reproducible Immobilization Techniques Using TiO2 for Photocatalytic Degradation of Aquatic Pollutants

Two main routes of methods for the preparation of photocatalytic active titanium dioxide films on glass substrates were investigated: (1) the use of titanium dioxide powder and (2) the in situ generation of the catalyst via hydrolysis of titanium tetraisopropoxide (TTIP) or TiCl₄. The activities of the catalyst films were evaluated by measuring the degradation of dichloroacetic acid (DCA), clofibric acid, and terbuthylazine used as model organic compounds. The concentration decrease of DCA and the concentration increase of chloride ions as the decomposition product allowed to distinguish between photocatalytic degradation of DCA and adsorption onto the TiO₂ films. Furthermore, TiO₂ films of the commercially available materials P25 (Degussa) and Hombikat UV100 (Sachtleben Chemie) were used to investigate whether there was a difference in the degradation pathways of terbuthylazine as a model compound. For the experiments mini flow‐through reactors were constructed. The investigated immobilization techniques were easy to handle without need of any expensive equipment. All TiO₂ coatings showed good photocatalytic activities and mechanical stabilities with efficient long‐term stabilities. The best immobilization reproducibility was achieved by the spray coating technique and by the in situ method with the dipping sol‐gel process starting by TTIP. During the continuous use of the TiO₂ films no TiO₂ particles were found in the irradiated solutions.     

Quantitative evaluation of a passively leveled ocean bottom seismometer

A problem in the use of ocean bottom seismometers is the difficulty in leveling the sensors while ensuring good coupling to the seafloor. We have investigated the coupling characteristics of the seismic sensors in the new ONR ocean bottom seismometer. In the deployable sensor package for that instrument, a three-component seismometer set is suspended on a 2-axis passive leveling gimbal and is immersed in a viscous fluid. We report tests, conducted in a seismic vault, comparing the output of a gimbaled seismometer set to that of a set rigidly coupled to the ground. Our results show that the degree to which the gimbaled set is coupled to ground motion is a function of the viscosity of the coupling fluid. The coherence between the two sensor sets is poor (<0.4) at some frequencies within the band of interest (0.15 to 20 Hz) and on some components when the viscosity of the coupling fluid is comparatively low (14 Pa-s or 0.16 kSt kinematic viscosity). In addition, the outputs of some components over portions of this frequency band are attenuated and are phase-shifted relative to the outputs of the set rigidly coupled to the ground. Coherence and phase response similarity improve as the viscosity of the coupling fluid is increased. With a coupling fluid viscosity of 980 Pa-s (10 kSt), coherence and phase agreement between the two sensor sets is good (>0.9) across nearly the entire band of interest on all three components. A simple analytical model of the gimbaled seismometer set as a damped, driven, compound-pendulum provides a basis for understanding the test results.