Sediment Pollution: Solving "Rill" Problems Using RECPs
Sediment pollution causes an estimated $16 billion in environmental damage annually. Sediment is the most common pollutant in rivers, streams, lakes, and reservoirs, causing such negative effects as temperature...

Monitoring and Quantifying Rate-Limited Mass Transfer Using Geoelectrical Measurements
Non-Fickian solute-transport behavior has been observed at research and aquifer remediationsites in diverse geologic settings. Anomalous behavior such as concentration rebound, long breakthrough...

Power Shift
Engineers designing a Manhattan skyscraper with offices in the lower floors and residences in the upper found that they had to employ several unusual methods to accommodate client needs....

Weighing Anchors
Modern anchorage systems offer design engineers and contractors unprecedented choice in load transfer mechanisms. Some anchors are highly specialized, while others are appropriate for...

Optimization of the Aquifer Remediation Costs and Design with Pulsed Pumping
(No paper) Pump-and-treat is a common technique for the remediation of contaminated aquifers. However, slow kinetic mass transfer at sites contaminated with organic compounds may reduce...

Impacts of CSO Swirl Concentrator on Dissolved Oxygen Concentrations in the Anacostia River
Purpose: To assess impacts of the CSO control, two continuous monitoring stations were located upstream and downstream from the CSO outfall. The monitors recorded dissolved oxygen (DO),...

Design-Build & Co.: A Brave New World
There are many inherent risks in overseas work. These are made greater by current project delivery methods, such as design/build operate transfer, and build own operate transfer. The author...

Optimal Geometric Shape of a Surface Aeration Tank
This paper presents the results of a laboratory investigation on three cross-sectional shapes?square, rectangular and circular of surface aeration tanks, without any baffles, to find out...

Upper Chehalis River Pollutant Capacity and Load Allocations
Dry season water quality was evaluated in the Upper Chehalis River in western Washington state, focusing on low dissolved oxygen (DO), and using the Total Maximum Daily Load (TMDL) process....

Plans for Testing and Evaluating the New Autoventing Turbines at TVA's Norris Hydro Project
As part of TVA's Hydro Modernization Program, the two 59-year old Francis turbines at Norris Dam have been upgraded with new units. In conjunction with TVA's...

The Importance of Water Depth for Sparger Performance
As part of TVA Hydro Modernization Program, the two 59-year old Francis turbines at Norris Dam have been upgraded with new units. In conjunction with TVA's Reservoir Releases...

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...

An Experimental Study on the Use of Constructed Wetlands for Stormwater Management
The purpose of this study is to compare the pollutant removal effectiveness of selected wetland vegetation such as cattails, reeds, and bulrushes by using laboratory bucket wetlands. Pollutants...

Lake Number: A Long-Term Lake Water Quality Predictor
A seasonal maximum Lake number was found to be a good predictor for volume averaged water temperatures, maximum water temperatures near lake bottom, seasonal stratification characteristics,...

Modeling of Surface Water Pumps in TVA Reservoirs
This paper describes the numerical simulation of surface water pump perforniance at Cherokee and Douglas Dams. The modeling objective was to determine the surface water pump initial velocities...

Simulation of Dissolved Oxygen in Sacramento-San Joaquin Delta
A one-dimensional model has been developed to simulate water quality in a complex multi-channel estuarine system. The model utilizes a Lagrangian reference frame for transport computations....

An Object-Oriented Approach to PC Finite-Element Solutions
A methodology for developing a finite-element program with a variety of applications within civil engineering is presented. Application include simple structural analysis, groundwater...

Clarifier Enhancements Yield Excellent Performance
The critical role of final clarifiers in meeting effluent permit requirements in indisputable. Poor performance of the final clarification step may adversely affect effluent quality. Experience...

A Coupled Mass Transfer and Surface Complexation Model for Uranium (VI) Removal from Wastewaters
A remediation technique has been developed for removing uranium (VI) from complex contaminated groundwater using flake chitin as a biosorbent in batch and continuous flow configurations....

Optimization Studies of Anaerobic Expanded Bed Reactor Pretreatment of Domestic Wastewater
In recent years the advent of the anaerobic expanded bed reactor (AEBR) has made possible the treatment of wastewaters of comparatively lower strength than have traditionally been treated...

 

 

 

 

Return to search