The identification and location of buried containers via non-destructive testing methods

The problem of identifying and locating containers of hazardous materials located beneath the ground surface or under water can be solved by either somThe conclusions section gives recommendations as to where each method is most applicable, as well as a comparison of each method on the basis of cost,     

Instrumentation for monitoring field performance of the Cincinnati GCL test plots

Fourteen full-scale cover systems were constructed at a site in Cincinnati, Ohio, to understand better the strength capability of various GCLs as a component in cover systems. Four different geosynthetic clay liner (GCL) products were installed in full-scale cover systems on two different slopes. The main objective of the project was to monitor the internal shear strength of the GCLs over time. This required in-situ yet economic instrumentation. Instruments were designed, calibrated and installed in the test plots in order to monitor the moisture content of the subsoil and moisture content within the bentonite component of the GCL. In addition, total and differential deformations of the GCLs were monitored. The focus of'this paper is to report the details of instrumenting the GCLs rather than to report on specific GCL performance.     

Use of a very-low-frequency electromagnetic method at 9.5 kHz to detect buried drums in sandy soil

A detailed study of the very-low-frequency electromagnetic (VLF-EM) method was undertaken at a single field site where a prescribed distribution of burResults indicated that the technique will undoubtedly detect and delineate any typical dump site with predominantly metal (usually steel) drums. SingleIsolated plastic drums are very difficult to detect; however, a large group with highly conductive contents could probably be detected.A quite unexpected result was that single, empty 40 gallon plastic drums can be detected to three feet of soil cover. Theoretical considerations indicaIt remains to show if these same conclusions will hold true in a more general soil type, one which contains a significant clay fraction.     

Geotechnical design considerations for geomembrane lined slopes: Slope stability

The design of geomembrane lined containment systems is a multi-faceted problem requiring the combined talents of many diverse disciplines. One of these disciplines is that of geotechnical engineering, within which falls the topic of soil slope stability. Since the integrity of the liner is dependent on this support system its proper design is of obvious importance. This paper addresses various approaches of soil slope stability and also includes the stability of cover soils which are often placed above the geomembrane for its protection. Related topics of anchor trench design at the top of the slope and of post-construction stability problems will be treated in subsequent papers.     

Synthesis and antimicrobial evaluation of nitazoxanide-based analogues: identification of selective and broad spectrum activity

A library composed of nitazoxanide-based analogues was synthesized and assayed for increased antibacterial efficacy against the pyruvate-ferredoxin oxidoreductase (PFOR) using microorganisms Helicobacter pylori, Campylobacter jejuni and Clostridium difficile. Derivatives were found to recapitulate and improve activity against these organisms and select analogues were tested for their ability to disrupt the PFOR enzyme directly. The library was also screened for activity against staphylococci and resulted in the identification of analogues capable of inhibiting both staphylococci and all PFOR organisms at low micromolar minimum inhibitory concentrations with low toxicity to human foreskin cells.