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Earthquake codes often times classify the subsoil based on their shear wave velocities which are mostly calculated based on the situ static conditions. However, it has been shown by various researchers that saturated sands exhibit a softening behavior under cyclic conditions. As a result of this behavior the surface response may be significantly affected by the existence of ground water. In this study, the effect of depth of water table on the seismic response of sand deposits is investigated. [ABSTRACT FROM AUTHOR]

Historically, most environmental occurrence research has focused on the parent compounds of organic contaminants. Research, however, has documented that the environmental transport of chemicals, such as pesticides and emerging contaminants, are substantially underestimated if transformation products are not considered. Although most examples described herein were drawn from research conducted by the U.S. Geological Survey, such results are generally reflective of those found in other parts of the world. Results from a study of 51 streams in the Midwestern United States found that transformation products were seven of the ten most frequently detected pesticide compounds in late spring runoff (after application of pre-emergent herbicides), and nine of the ten most frequently detected compounds in fall season runoff (during and after harvest). In fact, 70% of the total herbicide concentration in water from the Mississippi River Basin was from transformation products. Results from a study of 86 municipal wells in Iowa found the frequency of detection increased from 17%, when pesticide parent compounds were considered, to 53%, when both parents and transformation products were considered. Transformation products were 12 of the 15 most frequently detected compounds for this groundwater study. Although studies on transformation products of synthetic organic compounds other than pesticides are not as common, wastewater treatment plant discharges have repeatedly been shown to contribute such transformation products to streams. In addition, select detergent transformation products have been commonly found in solid waste in the 1000's mg/kg. These findings and many others document that transformation products must be considered to fully assess the potential environmental occurrence of chemical contaminants and their transport and fate in various compartments of the hydrologic system. [ABSTRACT FROM AUTHOR]

The database on tritium concentrations in streams, atomic lakes, ground waters and well waters at the Semipalatinsk Nuclear Test Site (STS) is by no means extensive, given the scale of nuclear testing undertaken at the site in the past. Here, we highlight the extent of the present database by summarising all of the readily accessible (published) data on tritium levels in the various waters of interest. In addition, we present new data on tritium gathered in the course of fieldwork in 2004 and 2005, by participants in the SEMIRAD 2 Project. We also review the status of present knowledge in regard to the mobility of tritium within and off the STS, by focussing on specific case studies, and offer suggestions as to the shape future research endeavours might take that, in our opinion, would be most cost effective. [ABSTRACT FROM AUTHOR]