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in creator/contributor: "Siegrist, Robert L."  
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[Task 1.] Biodenitrification of low nitrate solar pond waters using sequencing batch reactors. [Task 2.] Solidification/stabilization of high strength and biodenitrified heavy metal sludges with a Portland cement/flyash system

Description: Process wastewater and sludges were accumulated on site in solar evaporation ponds during operations at the Department of Energy's Rocky Flats Plant (DOE/RF). Because of the extensive use of nitric acid in the processing of actinide metals, the process wastewater has high concentrations of nitrate. Solar pond waters at DOE/RF contain 300-60,000 mg NO{sub 3}{sup {minus}}/L. Additionally, the pond waters contain varying concentrations of many other aqueous constituents, including heavy metals, al… more
Date: September 22, 1995
Creator: Figueroa, Linda; Cook, Nevis E.; Siegrist, Robert L.; Mosher, John; Terry, Seth & Canonico, S.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Stability of purgeable VOCs in water samples during pre-analytical holding: Part 1, Analysis by a commercial laboratory

Description: This study was undertaken to examine the hypothesis that prevalent and priority purgeable VOCs in properly preserved water samples are stable for at least 28 days. (VOCs are considered stable if concentrations do not change by more than 10%.) Surface water was spiked with 44 purgeable VOCs. Results showed that the measurement of 35 out of 44 purgeable VOCs in properly preserved water samples (4 C, 250 mg NaHSO{sub 4}, no headspace in 40 mL VOC vials with 0.010-in. Teflon-lined silicone septum c… more
Date: October 1, 1996
Creator: West, Olivia R.; Bayne, Charles K.; Siegrist, Robert L.; Holden, William L.; Scarborough, Shirley S. & Bottrell, David W.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Alkaline dechlorination of chlorinated volatile organic compounds

Description: The vast majority of contaminated sites in the United States and abroad are contaminated with chlorinated volatile organic compounds (VOCs) such as trichloroethylene (TCE), trichloroethane (TCA), and chloroform. These VOCs are mobile and persistent in the subsurface and present serious health risks at trace concentrations. The goal of this project was to develop a new chemical treatment system that can rapidly and effectively degrade chlorinated VOCs. The system is based on our preliminary find… more
Date: June 1, 1996
Creator: Gu, Baohua & Siegrist, Robert L.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

(Contaminated soil)

Description: The traveler attended the Third International Conference on Contaminated Soil, held in Karlsruhe, Germany. The Conference was a status conference for worldwide research and practice in contaminated soil assessment and environmental restoration, with more than 1500 attendees representing over 26 countries. The traveler made an oral presentation and presented a poster. At the Federal Institute for Water, Soil and Air Hygiene, the traveler met with Dr. Z. Filip, Director and Professor, and Dr. R. … more
Date: January 8, 1991
Creator: Siegrist, Robert L.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Measurement error potential and control when quantifying volatile hydrocarbon concentrations in soils

Description: Due to their widespread use throughout commerce and industry, volatile hydrocarbons such as toluene, trichloroethene and 1,1,1-trichloroethene routinely appear as principal pollutants in contaminated sites throughout the US and abroad. As a result, quantitative determination of soil system hydrocarbons is necessary to confirm the presence of contamination and its nature and extent; to assess site risks and the need for cleanup; to evaluate remedial technologies; and to verify the performance of… more
Date: January 1, 1990
Creator: Siegrist, Robert L.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Development and implementation of soil quality and cleanup criteria for contaminated sites

Description: A critical but vexing problem with contaminated land has always been assessing the significance of contamination and the degree of cleanup required for contaminated soils and sediments. Various approaches have evolved to address this difficult issue and debate continues over which is the most appropriate. With the growing number of contaminated sites, the majority of which are non-catastrophic, interest in criteria-based approaches has grown. While there are difficulties associated with the dev… more
Date: January 1, 1990
Creator: Siegrist, Robert L.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Stability of purgeable VOCs in water samples during pre-analytical holding. Part 2: Analyses by an EPA regional laboratory

Description: This study was undertaken to examine the hypothesis that prevalent and priority purgeable VOCs in properly preserved water samples are stable for at least 28 days. For the purposes of this study, VOCs were considered functionally stable if concentrations measured after 28 days did not change by more than 10% from the initial values. An extensive stability experiment was performed on freshly-collected surface water spiked with a suite of 44 purgeable VOCs. The spiked water was then distributed i… more
Date: March 1, 1997
Creator: West, Olivia R.; Bayne, Charles K.; Siegrist, Robert L.; Holden, William L. & Bottrell, David W.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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