Modeling Two-Dimensional Subsurface Flow, Fate and Transport of Microbes and Chemicals
A two-dimensional model to simulate the subsurface flow, microbial growth-degradation, and transport and biodegradation of chemicals in groundwater environments (2DFATMIC) is developed....

In-Situ Bioremediation Using a Recirculation Well
An existing model (Semprini and McCarty, 1991; 1992) of in-situ bioremediation using methanotrophic bacteria for degradation of volatile organic compounds was modified to simulate use...

Primary Metals and Criteria for Water use in the Columbia River, British Columbia
We assessed primarily concentrations of lead, cadmium, copper, zinc and water hardness in the Columbia River between Birchbank and Waneta. Water quality in this reach of the river is affected...

Electro-Osmotic Removal of Nitrates from Soils
Nitrate migration to ground and surface waters is a serious U.S. contamination threat. Electro-osmosis may be a more effective means for soil reclamation than leaching or chemical treatment....

Subsurface Drip Irrigation Can Reduce Pollution
Several researchers have indicated that precise subsurface drip (SSD) application of irrigation water can be effectively used to reduce pollution of the aquifer when irrigating with reclaimed...

Lead is a Four-Letter Word
New regulations and strict enforcement make it difficult and expensive to remove lead-laden coatings from steel structures. Lead-based primers and paints are not considered hazardous as...

Overmining Causes Undermining(It's a Mad Mad River)
Instream aggregate mining has caused significant problems and expense to California bridges. Riverbed degradation on the order of 3-5 m (9-15 ft) beneath waterway crossings within actively...

Chemical Resistance of Thermosetting Resins Used for Cured-in-Place Pipe
This paper summarizes the chemistry, short term physical properties, and long term chemical resistance for representative epoxy vinyl ester, epoxy, and polyester resins that are currently...

Getting Ahead of Snow and Ice
Winter maintenance is not the same anymore. New weather forecasting technologies are permitting snow and ice fighters to better predict when unsafe winter weather conditions will occur....

Snow and Ice Control in Japan and United States
Both Japan and the United States experience severe winter conditions that require major resources and large expenditures for maintaining highways. The maritime climate that prevails in...

Interactive Digital Image Feature Analysis as Applied to Cement and Concrete Microstructural Investigations
A novel procedure involves interactive chemical image analysis of separable features in the backscattered image. In this procedure a backscatter image is acquired by the image analysis...

Treatment of Calcareous Expansive Clays
The geology, climatic condition and the environment of extreme disintegration, strong hydration and restrained leaching have a large influence on the formation of expansive clays in the...

The Copper-Clad Library
The design vocabulary for the new Phoenix Central Library includes saddlebags, power bellies, tensegrity and corrugated siding. The saddlebags are copper-clad, steel-framed core structures...

Whose Risk Is It, Anyway?
Near the now-closed Smuggler Mine in Aspen, Colo. toxic lead sits beneath the grass of area residents' yards. A major portion of soil in the area has lead above the EPA action...

Review of NPP Concrete Degradation Factors and Assessment Methods
Degradation of concrete in nuclear power plant (NPP) structures can be an age-related phenomena. Several research programs have been initiated by the U.S. Nuclear Regulatory Commission...

VOCs: The New Effluent
The Clean Air Act of 1990, in addition to many state and local regulations, has officials of publicly-owned treatment works (POTWs) shifting their focus, and funds, to air toxic emissions...

Densification/Creep Behavior of Experimental Glass-Ceramic Waste Forms for Immobilization of High-Level Calcined Waste at the Idaho Chemical Processing Plant
A mixture of simulated high-level calcined waste (HLW) and Frit additives was hot isostatically pressed (HIPed) to a dense glass-ceramic waste form. A densification mapping software was...

Random Initial Heterogeneity and Degradation in Brittle Materials
The question of implementation of the initial state of the material is addressed. The problem is tackled by assuming random initial values for a relevant variable, within a prespecified...

The Small Mars Rover
Mars rover is one of the principal technical means intended for studying the surface of Mars. The first Mars rover was delivered to the Mars surface in 1971 and was designed for studying...

Chemical Analysis in Space Exploration: A Lunar-based Chemical Analysis Laboratory (LBCAL)
Many questions need to be answered before humans can be supported for extended periods in space - an environment inimical to terrestrial life. While some questions of a physiological nature...

 

 

 

 

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