Alachlor Transport in Laboratory Soil Columns
Spraying of agricultural chemicals result in their travel downward through the unsaturated zone and adsorption to the surrounding soil. Infiltration from rainfall and irrigation solubilize...

Predicting Transport of Organics through Soil Columns using Distributed Mass-Transfer Rates
A numerical model to describe contaminant transport through soil columns, including distributed mass-transfer, is developed. Both a gamma distribution and a lognormal distribution are...

Santa Ana River Mainstem Project
The Santa Ana River Mainstem Project consists of seven major features including the construction of 550 ft. high earth and rockf ill dam; raising the embankment by 28 feet of Prado Dam,...

Delineating Subsurface Contamination Using Geostatistical and Non-Intrusive Geophysical Methodologies
Electromagnetic (EM) conductivity surveys are becoming a more practiced technique in screening for contamination of soil and groundwater. This non-intrusive geophysical approach detects...

Systems for Forecasting Flows and Their Uncertainty
Discussed are design issues of distributed systems for operational flow forecasting. Results of sensitivity analyses are presented which illustrate forecast flow dependence on model discretization...

Design Alternatives for Protection of the Santa Ana River Interceptor Sewer
The Santa Ana River Interceptor Sewer (SARIS) line buried within the floodplain of the Santa Aria River is being threatened by long term degradation of the river bed at the pipeline crossings,...

Small Inocula Can Effect In Situ Biodegradation
This is the first report of colonization of soil by small numbers of a genetically engineered microorganism. The study suggests that the addition of small inocula of D5 to contaminated...

Studies on the Erosion of a Compacted Soil
In the management of water there are certain applications in which compacted soil is used (i.e., dams, embankments, levees, spiliways, and channels). Engineers rely primarily on field...

CHEMFLO Modeling of Aquifer Bioremediation in Vadose Zone
This paper deals with bioremediation in the vadose zone with an emphasis on using numerical models as a tool to ensure that the concentration of nutrients is maintained at a required level....

Development of Remediation Technologies Simulators
This paper summarizes on.going efforts to develop software for simulating various in situ, subsurface remediation technologies to improve remediation selection, design, and operation....

European Progress on river Renaturalisation
Most restoration projects in Europe have been designed to maximise species richness with little regard for channel stability. To recreate a sustainable natural channel it is necessary...

Role of Vegetation in Hydraulics of Channel Restoration
Boundary layer theory is used to develop a backwater model for flows through vegetated waterways which can be employed to approximately estimate flow depth variation in channel restoration...

Dredging in the Southern Sacramento-San Joaquin Delta
The California Department of Water Resources and the United States Bureau of Reclamation are jointly conducting an environmental study and are proposing to release a draft Environmental...

Maryland SHA's Procedure for Assessing Existing Bridges for Scour Vulnerability and for Rating Unknown Foundations
The Maryland State Highway Administration developed a recommended screening procedure for rating existing bridges for Item 113, Scour Critical Bridges, in the National Bridge Inventory...

Economic Risk Analysis as a Research Directing Paradigm
Risk analysis could be used to direct a manageable, prioritized strategic plan for evaluating bridge scour research needs. Through risk analysis, the costs of research and the potential...

Utilizing Geomorphic Analogs for Design of Natural Stream Channels
Engineering guidelines for the design of stable rock armored channels are well established. However, few guidelines exist for designers involved with the reconstruction of channels with...

Selection of Sediment Transport Relations: Part I, Review of Sediment Transport Comparisons
There are a great number of sediment transport relations in existence in the world today. The engineer is often faced with the problem of choosing the most appropriate relation for the...

Selection of Sediment Transport Relations Part III: Numerical Ranking of Sediment Transport Relations
The emphasis of this paper is the methodology for the selection of sediment transport relations and is applicable for analysis of any sediment transport relation. However, to illustrate...

Reduction of Sediment Loads in DEC Streams
The U.S. Army Corps of Engineers, Demonstration Erosion Control (DEC) project is actively involved in the stabilization and restoration of many drastically disturbed incising streams in...

Distributed Hydrologic Modeling of Humid Regions
Distributed physically-based hydrologic modeling of humid watersheds with shallow soils is complicated by non-Hortonian runoff production mechanisms. This paper presents a numerical experimental...

 

 

 

 

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