Potential for Nitrate Removal from Groundwater Supplies Using Biological Deintrification
Nitrate concentrations in groundwater supplies have been increasing over the years throughout many areas in the U. S. to the point of posing potential health dangers to a multitude of...
Water Diversion at Low-Level Waste Disposal Sites
Shallow depth to groundwater, surface drainage, and subsurface flow during storm events are major environmental concerns of low-level radioactive waste management operations in humid regions....
A Systems Approach for Wasteload Allocations
A methodology for determining an optimal periodic permit for a single discharger situation was developed which accounts for effluent variability, as well as the variability of the receiving...
Fate and Transport of Metals in a River System
A steady-state model was developed that describes the fate of metals in a shallow river system. Settling and resuspension of solids were defined through empirical equations relating a...
Simplified Methods to Predict the Fate of Metals in Rives
Heavy metal contamination of rivers is of increasing concern to society. To help predict the fate of metals in rivers, researchers have developed computer models to simulate speciation...
NCASI Enhancements of the QUAL-II Model
The mathematical water quality model QUAL-II has been modified to reflect advances in the understanding of algal, nutrient, and light interactions. Code changes were also made to incorporate...
Predicting Lake-Chain Quality with Augmentation
Steady-state mass-balance models of lake phosphorus are analyzed with regard to predicting augmentation (or dilution) effects. One form of these models employs a retention coefficient...
The Use of Activated Carbon as a Polishing Step for Treatment of Industrial Plating Wastewaters
An activated carbon adsorption process was utilized as a polishing step following the precipitation (hydroxide or sulfide) process. Zinc and cadmium were the metals studied. Since plating...
Industrial NPDES Toxicity Goals
Biological monitoring of NPDES (National Pollution Discharge Elimination System) effluents is becoming a reality in several EPA regions. While the advantages are genuine the loopholes...
Wetland Protection Regulations: A Technical Perspective
This paper summarizes the technical basis for the application of wetland protection regulatory schemes upon a number of typical environmental engineering and related projects. A number...
Age-Specific Cancer Risk Analysis for a Population Exposed to Contaminated Drinking Water
Recent developments in the methodology for estimating cancer risk for environmental contaminants exhibit promise for improved predictability of risk analyses based on EPA risk guidelines....
Impacts of Stormwater Runoff on Receiving Waters
A planning methodology to assess the impact of stormwater runoff on streams in Vermont is demonstrated. The methodology, which is based on a statistical representation of runoff and stream...
A Study of River Foaming and its Possible Causes
Foaming has been observed on uncontaminated upland streams draining watersheds having no human related development. Because water alone will not foam when agitated, the presence of these...
Significance of In-Stream Denitrification
In-stream denitrification rates were calculated using a simultaneous nitrogen and dissolved oxygen mass balancing technique. Anaerobic, laboratory, incubation of stream bottom samples...
Development of a Simplified Nitrogen Mass Balance Model in a Macroalgae Dominated System
A seasonably variable nitrogen uptake rate has been established for Ulva in Mumford Cove, Conn. This rate has been verified using three separate water quality analyses each of which assume...
PCB Contamination of a Mass. Harbor: Technical Challenges for a Remedial Solution
The highest priority uncontrolled site in Massachusetts, the New Bedford Harbor Superfund site, is contaminated with high concentrations of PCBs. The magnitude and nature of contamination,...
Quantifying the Exposure
Methods of categorizing and modeling of exposure will be presented. The use of modeling for the estimation of population exposure will also be examined and some errors inherent with such...
Microcomputer Methods for Toxicants in Ground Waters and Rivers
This paper describes a program written for the IBM personal computers to assess the fate of toxicants in ground waters and in rivers. The algorithms in the program were selected from a...
Arsenic Contamination of Private Potable Wells
The results of a series of water testing programs of private residential wells in Pepperell, Massachusetts showed that of 301 wells tested, approximately 12 percent exhibited arsenic levels...
Underground Oil Lens Management at John F. Kennedy International Airport
Observation wells plumbed using a water surface detector and standard topographic interpolation techniques were used to establish the hydraulic gradient of the groundwater and the presence...
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