Recent field work conducted on Mount Rainier and Mount Adams, Washington, and Pico de Orizaba, Mexico (Bowman et al., 2003; Zimbelman et al., 2003) has concentrated on assessing volcano rockmass strength for use in edifice stability studies. Preliminary rockmass strengths of these volcanoes have been measured using a combination of point load index testing, direct shear testing on discontinuities, uniaxial compression testing, and vane shear testing on discontinuity fillings. Because of the extreme height of several of these volcanoes and the difficulty in transporting loads to and around the edifice areas, it is imperative to use equipment with the least possible weight and size. A point load index test device for use in these conditions of high altitude, temperature extremes, and difficulty in transporting loads should be light, small, field repairable, and easy to operate, particularly with the use of gloves. This has necessitated the development of a new point load index device for use in these conditions. This new device must be significantly lighter than previously available units to be useful in these difficult conditions. Existing commercial point load index test devices currently or previously available are both too heavy and bulky for transport to the edifices of many volcanoes. Many of the units weigh in excess of 20 kg. At these weights, one person can only carry the point load index device, not including other field supplies, equipment, and climbing gear. Table 1 lists the specifications of several commercially available point load index devices currently or previously available. View this table: Table 1. Existing commercially available point load test devices. At the start of our investigation into a lighter, more portable point load index device, we modified a commercially available ELE International unit to reduce the weight of the device by removing the base plate and using a smaller pressure gauge. After …

The present study presents temperature measurements taken across the vadose zone at three piezometer-nest sites in the Albuquerque Basin. A new sensor having a relatively fast response time in air allows temperatures to be measured in the vadose zone every meter going down a piezometer at ∼2 m/min. This technique yields good depth resolution of temperature data. The resulting temperature–depth profile at one of the sites in the Albuquerque Basin (Lincoln Middle School) is noticeably curved, indicating a surface temperature change or the presence of fluid movement. The best statistical fit to the data is the expression representing a single temperature step of 3.7–3.8°C occurring ∼20 years before the piezometer logging (the suggested temperature increase occurred ∼1984–1985). From aerial photos it is noted that significant development occurred near and around the piezometer site between 1982 and 1986. During this interval natural vegetation was scraped off the ground, nearby roads were constructed and paved with asphalt, and houses were built across the two streets passing near the piezometer nest. The large amount of suggested ground-surface warming appears to directly correlate with urbanization and development.

Research Article| January 01, 2006 Past Valley Widening and Recent Creep beside the Lower Mississippi Valley RICHARD J. LUTTON RICHARD J. LUTTON 15 Crestwood Drive, Vicksburg, MS 39180 Search for other works by this author on: GSW Google Scholar Environmental & Engineering Geoscience (2006) 12 (1): 13–24. https://doi.org/10.2113/12.1.13 Article history first online: 09 Mar 2017 Cite View This Citation Add to Citation Manager Share Icon Share Facebook Twitter LinkedIn MailTo Tools Icon Tools Get Permissions Search Site Citation RICHARD J. LUTTON; Past Valley Widening and Recent Creep beside the Lower Mississippi Valley. Environmental & Engineering Geoscience 2006;; 12 (1): 13–24. doi: https://doi.org/10.2113/12.1.13 Download citation file: Ris (Zotero) Refmanager EasyBib Bookends Mendeley Papers EndNote RefWorks BibTex toolbar search Search Dropdown Menu toolbar search search input Search input auto suggest filter your search All ContentBy SocietyEnvironmental & Engineering Geoscience Search Advanced Search Abstract Tertiary strata are offset from the bluff at several places beside the broad valley of the Mississippi River in Mississippi.Most displaced blocks lie hidden under river water and floodplain, but the bluff at Vicksburg presents a partially exposed example. Block displacements there illustrate a mechanism of valley widening that operated before the geomorphic regime of the present. These displacements represent spreading of strata toward the valley in response to reductions of lateral confinement accompanying heavy river erosion nearby. Flat slip surfaces that developed in clayey strata during block displacements have facilitated recent movements as the meandering river impinged on the bluff. The foundations of two bridges at Vicksburg have experienced such creep-like movements in recent years. Localized plastic deformation has complicated the geologic picture near the bridges. Deformation features are confined to a single bed of marly limestone and the underlying layer of clayey marl. This plastically deformed couplet is contained within the much thicker assemblage of displaced blocks having horst-and-graben features. Plastic deformation of a bed that has subsequently been indurated to marly limestone indicates an origin well back in time, perhaps in the Oligocene. The structural fabric of the plastically deformed unit, however, indicates movement to the west and suggests some relation to the widening Pleistocene valley. You do not have access to this content, please speak to your institutional administrator if you feel you should have access.

Simulation of CO2 sequestration in deep geological formations is a multi-disciplinary effort involving the study of multi-phase flow of groundwater and carbon dioxide along with porous medium deformation caused by pore pressure increase. The latter can cause the ground surface to rise because of the reduction of the effective stress in the aquifer and consequent rock expansion. A preliminary analysis of CO2 sequestration in a brackish aquifer between 600 and 800 m below the Venice Lagoon is presented. Using available geological, geophysical, hydrologic, and geomechanical data, and with the aid of advanced numerical models, several scenarios are addressed to investigate the potential of the proposed solution as far as both the CO2 storage and the possible land uplift are concerned. The results show that with the most probable hydrogeological configuration the total amount of CO2 released from nearby thermo-power plants, i.e., 20 Mt/year, can be safely sequestered, with an expected city uplift over 10 years ranging between 7 and 13 cm, depending on well configuration. This would make up for most of the anthropogenic land subsidence experienced by Venice over the last half-century and could offset between 50 and 70 percent of the “acqua alta” that periodically floods Venice. The simulations, however, show a high sensitivity to sand permeability and compressibility, which points to the need for new field investigations before the present preliminary proposal may be turned into an actual feasibility study.

Research Article| April 01, 2005 Introduction to Theme Issue on Tracers in Hydrogeology CRAIG E. DIVINE CRAIG E. DIVINE 1ARCADIS G&M, 630 Plaza Drive, Suite 200, Highlands Ranch, CO 80129 Search for other works by this author on: GSW Google Scholar Author and Article Information CRAIG E. DIVINE 1ARCADIS G&M, 630 Plaza Drive, Suite 200, Highlands Ranch, CO 80129 Publisher: Association of Environmental & Engineering Geologists First Online: 09 Mar 2017 Online ISSN: 1558-9161 Print ISSN: 1078-7275 © 2005 Association of Engineering Geologists Environmental & Engineering Geoscience (2005) 11 (4): 293. https://doi.org/10.2113/11.4.293 Article history First Online: 09 Mar 2017 Cite View This Citation Add to Citation Manager Share Icon Share Facebook Twitter LinkedIn MailTo Tools Icon Tools Get Permissions Search Site Citation CRAIG E. DIVINE; Introduction to Theme Issue on Tracers in Hydrogeology. Environmental & Engineering Geoscience 2005;; 11 (4): 293. doi: https://doi.org/10.2113/11.4.293 Download citation file: Ris (Zotero) Refmanager EasyBib Bookends Mendeley Papers EndNote RefWorks BibTex toolbar search Search Dropdown Menu toolbar search search input Search input auto suggest filter your search All ContentBy SocietyEnvironmental & Engineering Geoscience Search Advanced Search Hydrogeologic tracing is an intuitive characterization technique that has been applied for a surprisingly long period of time: there are records of chaff being used as a tracer near the Jordan River in approximately 10 A.D., and quantitative experiments using salts and fluorescent dyes were first used in Europe in the late 1800s (see Käss, 1998, Chapter 1). By far, most historical applications of tracers were designed to delineate flow paths and determine transport times in karst systems; however, during the past couple of decades, the discipline of tracer hydrogeology has blossomed with an amazing diversity of applications. Tracers... You do not have access to this content, please speak to your institutional administrator if you feel you should have access.

Research Article| April 01, 2005 Simulation and Performance Assessment of Partitioning Tracer Tests in Heterogeneous Aquifers Elena Moreno-Barbero; Elena Moreno-Barbero 1ARCADIS G&M, 630 Plaza Dr., Suite 200, Highlands Ranch, CO 80129and Center of Experimental Study of Subsurface Environmental Processes, Environmental Science and Engineering Division, Colorado School of Mines, Golden, CO 80401 Search for other works by this author on: GSW Google Scholar Tissa H. Illangasekare Tissa H. Illangasekare 2Center of Experimental Study of Subsurface Environmental Processes, Environmental Science and Engineering Division, Colorado School of Mines, Golden, CO 80401 Search for other works by this author on: GSW Google Scholar Environmental & Engineering Geoscience (2005) 11 (4): 395–404. https://doi.org/10.2113/11.4.395 Article history first online: 09 Mar 2017 Cite View This Citation Add to Citation Manager Share Icon Share Facebook Twitter LinkedIn MailTo Tools Icon Tools Get Permissions Search Site Citation Elena Moreno-Barbero, Tissa H. Illangasekare; Simulation and Performance Assessment of Partitioning Tracer Tests in Heterogeneous Aquifers. Environmental & Engineering Geoscience 2005;; 11 (4): 395–404. doi: https://doi.org/10.2113/11.4.395 Download citation file: Ris (Zotero) Refmanager EasyBib Bookends Mendeley Papers EndNote RefWorks BibTex toolbar search Search Dropdown Menu toolbar search search input Search input auto suggest filter your search All ContentBy SocietyEnvironmental & Engineering Geoscience Search Advanced Search Abstract Characterization of dense non-aqueous phase liquid (DNAPL) in heterogeneous media represents a major challenge in the remediation process due to the complexity of DNAPL distribution in the subsurface. The partitioning interwell tracer test (PITT), which evaluates the relative transport of DNAPL-phase partitioning and conservative (i.e., non-partitioning) tracers, has recently been promoted as a way to quantify entrapped DNAPL mass in source zones. In some cases, the technique has been successfully applied to sites where DNAPL is present primarily at residual saturations. However, the effects of the geologic heterogeneity and DNAPL architecture on the performance and reliability of this technique have not yet been thoroughly examined. A systematic two-dimensional simulation study was conducted to evaluate the influence of DNAPL vertical distribution, well location, and geologic heterogeneity on the performance of the PITT for a total of 60 stochastic aquifer realizations. The aquifer hydraulic conductivity (K) distribution was defined using three different geostatistical parameter values describing the variance of the log K (⁠ \({\sigma}^{2}_{ln\ k}\) = [1.22, 0.75, 0.25]). A multiphase flow simulator was used to generate the source zone, allowing the DNAPL to distribute naturally. The tracer test simulations conducted using these various synthetic aquifers were specifically designed to quantify PITT performance for different degrees of heterogeneity. For cases where the aquifer is relatively heterogeneous and the DNAPL architecture is complex, PITT estimation efficiency averaged 48 percent (decreasing to 20 percent in certain scenarios) as a result of bypass flow and the limited tracer accessibility to lower hydraulic conductivity regions. While other studies have suggested the PITT technique may underestimate DNAPL saturation for these conditions, potential errors of this magnitude have not previously been reported. The results of this work underscore the importance of geological heterogeneity on PITT performance. You do not have access to this content, please speak to your institutional administrator if you feel you should have access.

Urban development is a high priority in Egypt. New Minia City, located on the eastern bank of the Nile River, approximately 250 km south of Cairo, is one of 16 new development communities. Urban development in New Minia City may encounter several geo-environmental problems. Karst conditions and structural features in the local heterogeneous bedrock limit its suitability for constructional purposes. In this research, suitability of the area for urban development was assessed using a geographic information systems (GIS)-based approach. A weighted GIS model that incorporated land use/cover, types of soil, karst feature distribution, fracture densities, slopes, distances to major faults and streams, road network, and city boundaries was established to create a map of site suitability for the city. Model weights were developed using the analytical hierarchy process (AHP) approach. Current urban land use within New Minia City falls into four classes of suitability. Approximately 7 percent of the area built by 2002 is in the low suitability class, which suggests that the map of site suitability can serve as a reliable base for planning sustainable development in New Minia City. The developed map of site suitability is effective for assessing and revealing ratings of suitability for urban development. Furthermore, the map of suitability provides the foundation for informed decision making in the development of New Minia City.

Paleoflood hydrology, as it developed in the 1970s, identified slackwater flood deposits (SWD) as the primary indicator of a historically high stage of a river, i.e., a “paleostage indicator.” Such SWDs are believed to have formed in eddies at the mouths of tributaries of rivers that caused sedimentation of sands and silts in topographically elevated locales relative to the present position of such rivers. If undisturbed by even larger floods, there is a reasonable likelihood that pedogenic processes will create a soil horizon within the SWD that can be age-dated using 14C. Thus an approximate age of the paleoflood can be estimated as well as the paleostage, i.e., the maximum flood stage. Using one-dimensional hydraulic models of bedrock channels and estimates of bed roughness described by Manning's coefficient, the paleoflood hydrologist employs the same tools as used by engineering hydrologists to estimate peak flood discharges, e.g., the step-backwater method. Consequently, geomorphologists and paleoflood hydrologists have been able to contribute their insight to flood-frequency analysis, previously the sole domain of engineering hydrologists. Some years have past since Environmental & Engineering Geoscience published a research paper on low-probability floods and their estimation (Malamud et al., 1996). Paleoflood hydrology is, however, a vibrant area of scientific research that has particular significance to dam safety and floodplain protection of critical structures, such as nuclear reactors, and to engineering geology and fluvial geomorphology in general. This monograph, by the principal actors in paleoflood hydrology, is rich in detail, definitive in scope, and of moderate cost ($75 hardback). Ancient …

The gypsy moth is one of the most devastating forest pests in North America. The Ohio Department of Agriculture, in common with other state agencies involved in the Gypsy Moth Suppression Program, uses aerial sketch mapping each year to map gypsy moth damage. We compare results obtained from Landsat 5 and Landsat 7 to locations determined by aerial sketch mapping to locate gypsy moth infestations in Ohio. The haze-corrected ratio of Landsat band 4 (near infrared) to band 3 (red) detects changes of leaf area. We subtract the ratio values from two dates to determine the change. As in previous studies, we search for the defoliation caused by the gypsy moth by subtracting the ratio values of frames acquired in early June and late June. Unlike previous studies, we use the subsequent refoliation that takes place between late June and late July as part of the signal. This is seen as large positive ratio subtraction values between early June and late June and large negative ratio subtraction values between late June and late July. Pixels that exhibit these attributes are candidates for gypsy moth defoliation. The use of three frames to analyze both defoliation and subsequent refoliation results in a stronger, less ambiguous signal of gypsy moth damage and pinpoints the locations of the most severe defoliation. The most severe defoliation often marks the location of egg masses. Although we reduced the ambiguity caused by agricultural anomalies, this procedure also detected areas with significant wild grapevine infestations.

Ninety years of historical landslide records were used as input to the Poisson and binomial probability models. Results from these models show that, for precipitation-triggered landslides, approximately 9 percent of the area of Seattle has annual exceedance probabilities of 1 percent or greater. Application of the Poisson model for estimating the future occurrence of individual landslides results in a worst-case scenario map, with a maximum annual exceedance probability of 25 percent on a hillslope near Duwamish Head in West Seattle. Application of the binomial model for estimating the future occurrence of a year with one or more landslides results in a map with a maximum annual exceedance probability of 17 percent (also near Duwamish Head). Slope and geology both play a role in localizing the occurrence of landslides in Seattle. A positive correlation exists between slope and mean exceedance probability, with probability tending to increase as slope increases. Sixty-four percent of all historical landslide locations are within 150 m (500 ft, horizontal distance) of the Esperance Sand/Lawton Clay contact, but within this zone, no positive or negative correlation exists between exceedance probability and distance to the contact.