| Variations in Field-Scale Nitrogen and Phosphorus Concentrations in Runoff as a Function of Land-Use Practice |
SEP 2004 |
22 pages |
| Authors:
William F. James; Harry L. Eakin; Carlos E. Ruiz; John W. Barko; ENGINEER RESEARCH AND DEVELOPMENT CENTER VICKSBURG MS ENVIRONMENTAL LAB
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 | The purpose of this research was to examine nitrogen and phosphorus concentrations in runoff at the field-scale level (i.e., homogeneous land-use plot) over a variety of land-use practices. Land-use practices included animal containment/barnyard areas, corn production fields, alfalfa and grass hayfields, Conservation Reserve Program (CRP) fields, and woodlots located in the upper Eau Galle River Watershed, west-central Wisconsin. The watershed is dominated by agricultural and dairy livestock land-use practices. Results ... |
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| Longitudinal Loading and Nutrient Compositional Gradients in an Agriculturally Managed Watershed in West-Central Wisconsin |
SEP 2004 |
15 pages |
| Authors:
William F. James; Carlos E. Ruiz; John W. Barko; Harry L. Eakin; ENGINEER RESEARCH AND DEVELOPMENT CENTER VICKSBURG MS
|
| The purpose of this research was to describe and quantify biologically labile and refractory nitrogen and phosphorus species, transformations, and loads along the longitudinal axis of a river draining an intensively managed agricultural watershed. Excessive nutrient runoff (primarily as phosphorus) in agriculturally managed watersheds is a primary cause for eutrophication of Corps of Engineers and other receiving waters. Because agricultural soils are often managed for crop uptake of nitrogen (N), ... |
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| Nutrient Loading Characteristics for Two Sub-watersheds Exhibiting Differing Agricultural Land-Use Practices |
SEP 2004 |
15 pages |
| Authors:
William F. James; Carlos E. Ruiz; John W. Barko; ENGINEER RESEARCH AND DEVELOPMENT CENTER VICKSBURG MS ENVIRONMENTAL LAB
|
| The purpose of this research was to describe and quantify biologically labile and refractory nitrogen and phosphorus constituents, transformations, and loads in the runoff of two sub-watersheds exhibiting differing agricultural land-use practices. Runoff was impacted by intensive row- cropping for corn production in one of the watersheds while the other one was impacted by dairy livestock management. |
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| Soil Phosphorus Compositional Characteristics as a Function of Land-Use Practice in the Upper Eau Galle River Watershed, Wisconsin |
SEP 2004 |
13 pages |
| Authors:
William F. James; Harry L. Eakin; Carlos E. Ruiz; John W. Barko; ENGINEER RESEARCH AND DEVELOPMENT CENTER VICKSBURG MS ENVIRONMENTAL LAB
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| The purpose of this research was to quantify biologically labile and refractory phosphorus species in source soils of an agricultural watershed that drains into a eutrophic Corps of Engineers reservoir. Eutrophication of receiving waters is strongly linked to the erosion and transport of particulate and soluble nutrients derived from the watershed landscape. In dairy and agricultural settings, amendment of soils with fertilizers and manure is usually based on crop nitrogen ... |
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| Watershed Modeling System Hydrological Simulation Program; Watershed Model User Documentation and Tutorial |
JUL 2002 |
43 pages |
| Authors:
Patrick N. Dellman; Carlos E. Ruiz; Colby T. Manwaring; E. J. Nelson; ENGINEER RESEARCH AND DEVELOPMENT CENTER VICKSBURG MS ENVIRONMENTAL LAB
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| The Hydrological Simulation Program-FORTRAN (HSPF) is an analytical tool designed to simulate hydrology and water quality in natural and man-made systems. HSPF is used to apply mathematical models to simulate the movement of water, sediment, and other constituents through watersheds. This analysis helps predict possible environmental problems in the watershed. With the growing need to care for and monitor the effects of man on the environment, it became apparent that ... |
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| Implementation of Dredging Risk Assessment Modeling Applications for Evaluation of the No-Action Scenario and Dredging Impacts |
DEC 2001 |
14 pages |
| Authors:
Patrick N. Deliman; Carlos E. Ruiz; Paul R. Schroeder; ENGINEER RESEARCH AND DEVELOPMENT CENTER VICKSBURG MS
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| This technical note describes the development of Dredging Risk Assessment Modeling Applications (DRAMA) for evaluation of the no-action scenario and the impacts of dredging operations without consideration of disposal. Implementation templates for these scenarios use existing dredging models to characterize exposure for the evaluation of potential human health and ecological risk. The models selected have been incorporated into the Framework for Risk Analysis in Multimedia Environmental Systems (FRAMES), a part ... |
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| Water Quality Additions to CASC2D - Taps |
SEP 2001 |
8 pages |
| Authors:
Patrick N. Dellman; Terry K. Gerald; Carlos E. Ruiz; ENGINEER RESEARCH AND DEVELOPMENT CENTER VICKSBURG MS
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| The purpose of this effort was the implementation of nutrient water quality components included in the Transport and Pollutant System (TAPS) into the CASC2D hydrology watershed model. The CASC2D model is still in development and is being improved, refined, and updated with new technology. Users of CASC2D need to have a thorough background in hydrology and numerical modeling. CASC2D is currently being restructured and an updated version (under a new ... |
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| Application of HSPF-AGCHEM Module Within the WMS for the LeSueur Basin |
JUL 2001 |
11 pages |
| Authors:
Patrick N. Dellman; Carlos E. Ruiz; Anthony S. Donigian; Thomas H. Jobes; E. J. Nelson; ENGINEER RESEARCH AND DEVELOPMENT CENTER VICKSBURG MS
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| This technical note presents the results of the incorporation of the Hydrologic Simulation Program-Fortran (HSPF) AOCHEM modules into the Watershed Modeling System (WMS). HSPF allows simulation of processes that affect water quality. Often the most significant of these processes are agriculture and chemical processes that take place on agricultural land segments. Such processes include application of pesticides and fertilizers. Included in HSPF are three modules that collectively are referred to ... |
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| Dredging Research. Volume 4, Number 1. Information from the Engineer Research and Development Center |
MAR 2001 |
8 pages |
| Authors:
Carlos E. Ruiz; Paul R. Schroeder; ENGINEER RESEARCH AND DEVELOPMENT CENTER VICKSBURG MS
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| Subaqueous capping is a remediation technique for contaminated sediments in an aquatic environment. The technique physically isolates contaminants through a layer of clean material placed over the contaminated sediments. Field measurements at the Duwamish River dredged material disposal site in Seattle Wash., were made to evaluate movement of contaminants from the contaminated dredged material deposit into the cap material. |
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| Recovery Version 2.0, A Mathematical Model to Predict the Temporal Response of Surface Water to Contaminated Sediments |
JAN 2001 |
50 pages |
| Authors:
Carlos E. Ruiz; Terry Gerald; ENGINEER RESEARCH AND DEVELOPMENT CENTER VICKSBURG MS ENVIRONMENTAL LAB
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| RECOVERY is a PC-based screening-level model to assess the impact of contaminated bottom sediments on surface waters. The analysis is limited to organic contaminants with the assumption that the water column is well-mixed. The contaminant is assumed to follow linear, reversible, equilibrium sorption, and first-order decay kinetics. The physical representation of a system by RECOVERY consists of a well-mixed water column (i.e., zero-dimensional) underlain by a vertically stratified sediment column ... |
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| Summary Report, Risk Assessment Modeling Workshop; 14-15 May 1998, New Orleans, Louisiana |
JUL 2000 |
282 pages |
| Authors:
Patrick N. Deliman; Carlos E. Ruiz; Jeffrey A. Gerald; ENGINEER RESEARCH AND DEVELOPMENT CENTER VICKSBURG MS ENVIRONMENTAL LAB
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| The Fate & Effects Advisory Committee (FEAC) identified the need for the development of models capable of providing information relating to the fate and effects of Military Relevant Compounds (MRCs) on both ecological and human resources. Requirements for better modeling capabilities of contaminant concentration over time for risk assessment were stated. In an effort to address the requirement, a work unit was initiated for the development ... |
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| RECOVERY: A Contaminated Sediment- Water Interaction Model. Dredging Operations Technical Support Program |
FEB 2000 |
29 pages |
| Authors:
Carlos E. Ruiz; Paul R. Schroeder; Nadim M. Aziz; ENGINEER RESEARCH AND DEVELOPMENT CENTER VICKSBURG MS ENVIRONMENTAL LAB
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| This report describes a screening-level model (RECOVERY) used to assess the long-term impact of contaminated bottom sediments on surface waters. The model couples contaminated interaction between the water column and the bottom sediment, as well as between the contaminated and clean bottom sediments. The analysis is intended primarily for organic contaminates with the assumption that the water column is well mixed. The contaminant is assumed to ... |
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| Review of Watershed Water Quality Models |
JAN 1999 |
33 pages |
| Authors:
Patrick N. Deliman; Roger H. Glick; Carlos E. Ruiz; ARMY ENGINEER WATERWAYS EXPERIMENT STATION VICKSBURG MS
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| This review was conducted to determine the current state of the art in watershed water quality modeling. Several available watershed water quality models were reviewed and rated with regard to their potential in being utilized as the building block for the development of a Corps of Engineers watershed water quality model. Watershed water quality models are currently being implemented for predicting watershed runoff water quality as influenced by land use ... |
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| Documentation on Limitations and Applicabilities of the Use of Off-the- Shelf GroundWater Models in Site Cleanup |
AUG 97 |
212 pages |
| Authors:
Carlos E. Ruiz; Mansour Zakikhani; Christian J. McGrath; Patrick N. Deliman; Stacy Howington; ARMY ENGINEER WATERWAYS EXPERIMENT STATION VICKSBURG MS
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| The U.S. Army Engineer Waterways Experiment Station Groundwater Modeling Team performed a broad review of available groundwater models and an assessment of Army modeling. The first step was a model screening based primarily on current and anticipated Army and Department of Defense needs, followed by a more rigorous evaluation. This report provides the initial evaluation of more than 12 groundwater models that were selected based on the screening criteria. The ... |
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| RECOVERY, A Mathematical Model to Predict the Temporal Response of Surface Water to Contaminated Sediments |
NOV 94 |
63 pages |
| Authors:
Jean M. Boyer; Steven C. Chapra; Carlos E. Ruiz; Mark S. Dortch; ARMY FOREIGN SCIENCE AND TECHNOLOGY CENTER CHARLOTTESVILLE VA
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| RECOVERY is a PC-based screening-level model to assess the impact of contaminated bottom sediments on surface waters. The analysis is limited to organic contaminants with the assumption that the water column is well mixed. The contaminant is assumed to follow linear, reversible, equilibrium sorption and first-order decay kinetics. The physical representation of a system by RECOVERY consists of a well-mixed water column (i.e., zero- dimensional) underlain by a vertically stratified ... |
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| Water Quality Studies in the Upper Yazoo Project Area, Mississippi |
NOV 91 |
186 pages |
| Authors:
Judith C. Pennington; Barry W. Bunch; Carlos E. Ruiz; Dennis L. Brandon; Thomas C. Sturgis; ARMY ENGINEER WATERWAYS EXPERIMENT STATION VICKSBURG MS ENVIRONMENTAL LAB
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| Potential effects of flood control structures on water quality in the Upper Yazoo Project (UYP) area is of concern. This study was designed to provide information in the following five subject areas: general water quality in the Yazoo River, general water quality in Bear Creek, effects of channelization in a selected reach of the Yazoo River, pesticide contamination in sediments of the UYP area, and baseline data on water quality ... |
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