Little Blue Valley Sewer District, Independence, Missouri

Little Blue Valley Sewer District, Independence, Missouri PDF Author: National Institute for Occupational Safety and Health
Publisher:
ISBN:
Category : Endotoxins
Languages : en
Pages : 36

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Little Blue Valley Sewer District, Independence, Missouri

Little Blue Valley Sewer District, Independence, Missouri PDF Author: National Institute for Occupational Safety and Health
Publisher:
ISBN:
Category : Endotoxins
Languages : en
Pages : 36

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Selected Water Resources Abstracts

Selected Water Resources Abstracts PDF Author:
Publisher:
ISBN:
Category : Water
Languages : en
Pages : 1140

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Clean Water Infrastructure and Wet Weather Flows Legislation

Clean Water Infrastructure and Wet Weather Flows Legislation PDF Author: United States. Congress. House. Committee on Transportation and Infrastructure. Subcommittee on Water Resources and Environment
Publisher:
ISBN:
Category : Science
Languages : en
Pages : 314

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Y2K, Will We Get There on Time?

Y2K, Will We Get There on Time? PDF Author: United States. Congress. House. Committee on Transportation and Infrastructure
Publisher:
ISBN:
Category : Transportation
Languages : en
Pages : 702

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Y2K + H20

Y2K + H20 PDF Author: United States. Congress. Senate. Special Committee on the Year 2000 Technology Problem
Publisher:
ISBN:
Category : Water quality management
Languages : en
Pages : 86

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Technical Approaches for Setting Site-Specific Nutrient Criteria

Technical Approaches for Setting Site-Specific Nutrient Criteria PDF Author: W. J. Warren-Hicks
Publisher: IWA Publishing
ISBN: 1843396394
Category : Science
Languages : en
Pages : 134

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Book Description
The purpose of this project was to develop a methodology for deriving site-specific nutrient criteria (SSNC) for surface waters, including streams and rivers, lakes and reservoirs, and coastal estuaries. The methodology was developed to extend the United States Environmental Protection Agency's regional nutrient criteria for localized conditions characterized by particular desired water quality requirements or designated uses. The proposed SSNC methodology provides local stakeholders with a recipe for estimating nutrient criteria consistent with site-specific water quality management goals and objectives. The SSNC methodology prescribes a three-tiered or sequential approach for defining concentrations of acceptable nutrients in relation to management goals and objectives. Each tier requires successively more site-specific data and information and also develops increasingly quantitative and technologically more detailed relationships between nutrients and stated water quality measurements (chlorophyll a, Secchi depth, dissolved oxygen). The SSNC process can be initiated at any tier, although most applications will likely progress from Tier 1. The derivation of Tier 1 SSNC relies extensively on existing data and regional nutrient criteria. Tier 2 adds additional, more site-specific data and estimates SSNC on the basis of statistical relationships between nutrients and the selected water quality parameters of interest. Tier 3 extends Tier 2 through the development of additional site-specific data and the application of site-specific, process-level water quality models to estimate the SSNC. Follow-up monitoring is a key component of all three tiers for assessing the effectiveness of the SSNC in achieving the desired water quality characteristics and making subsequent decisions about continued implementation or modification of the SSNC. Benefits: SSNC can serve as effective alternatives to regional criteria, which may fail to achieve or sustain locally desired water quality conditions. The proposed methodology prescribes an efficient and economical approach for achieving site-specific water quality objectives. The methodology develops SSNC on the basis of process-level understanding of relationships between nutrients and water quality objectives. The tiered approach permits a sequential, increasingly detailed and sophisticated analysis of relations between nutrients and desired water quality conditions. The results of the tiered SSNC methodology provide direct inputs to localized management and decision-making processes.

Pathogen Destruction Efficiency In High Temperature Digestion

Pathogen Destruction Efficiency In High Temperature Digestion PDF Author: Donald M. D. Gray (Gabb)
Publisher: IWA Publishing
ISBN: 1843396963
Category : Science
Languages : en
Pages : 196

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Book Description
The purpose of this research was to evaluate and compare various thermophilic anaerobic digestion processes for meeting U.S. EPA biosolids Class A pathogen standards. The project was split into three phases. Phase 1 screened three bench-scale thermophilic anaerobic process configurations at three different thermophilic temperatures based on their fecal coliform destruction efficiency. All three of the thermophilic process configurations tested were capable of achieving the Class A fecal coliform standard and were included in Phase 2. In Phase 2, bench-scale anaerobic digesters were fed primary sludge seeded with E.coli, helminth ova, poliovirus, and Salmonella to evaluate pathogen destruction. Two process configurations, the thermophilic single-stage and the two-stage mesophilic acid-phase/thermophilic methane-phase system, met Class A requirements at 50oC. In Phase 3, the single-stage thermophilic anaerobic digestion process was compared to the single-stage mesophilic process at full scale (1.5-MG digesters) based on fecal coliform and pathogen destruction, process performance, digested sludge dewaterability, and odor generation. Pathogen destruction and process performance comparisons of the various process configurations are presented for each phase of the study. Based on the fecal coliform data presented here, an empirical model was developed for quantitatively comparing multiple stage and single-stage thermophilic anaerobic digester performance. The model demonstrates that various combinations of thermophilic temperatures, staging, and residence times can achieve the Class A fecal coliform requirement. This study also suggests that anaerobic digesters operating in the lower thermophilic temperature range (approximately 50?C) are not only capable of achieving Class A requirements but may also produce digested sludges with less odor and lower volatile solids than digesters operating at higher thermophilic temperatures.

Sensor Technology for Water Quality Monitoring

Sensor Technology for Water Quality Monitoring PDF Author: A. C. Cannons
Publisher: IWA Publishing
ISBN: 1843396777
Category : Science
Languages : en
Pages : 72

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Book Description
Two methods for the detection of important human pathogens, Cryptosporidium parvum and Helicobacter pylori, were investigated: a fiber optic biosensor, and real time PCR. The mechanism for specific detection in both methods is recognition of specific DNA sequences in the target organisms. The biosensor that was used, the Analyte 2000, was originally developed for the detection of chemicals. It utilizes a fiber optic wave guide that propagates an evanescent light wave of very specific wavelength. The light excites fluorescent molecules bound to the waveguide, but not in the bulk solution, which theoretically enhances signal while reducing background interference. Attempts to develop this system for the detection of DNA were not successful due to poor detection of the target molecules. An assay analogous to a sandwich immunoassay was designed for use on the Analyte 2000. Specific oligonucleotide probes were designed to bind to the waveguides via biotin-streptavidin interaction, and were used to capture the target DNA. Pure target DNA representing unique genes in the organisms were synthesized by PCR. Detection of captured DNA was then attempted using an oligonucleotide detection probe designed to bind to the target. Two detection systems were employed: an indirect signal amplification system based on biotin-tyramide deposition, or direct detection of fluorescent signal from Cy-5 molecules. In all experiments performed there was very little difference between the signal generated with or without the target molecules. Many experiments were conducted to attempt to identify reasons for the poor signal. Signal was only of any significance when target amplicons were internally labeled with Cy-5 by PCR. Real time PCR as a method to detect the pathogens was also investigated. Though the PCR technique itself is very rapid, DNA extraction and purification requires preparation time. Filtration of up to one liter of well water, followed by concentration and "cleaning" Helicobacter pylori cells by immunomagnetic separation, was used to detect H. pylori seeded in a water source. Following cell lysis, the extracted DNA could be used directly in conventional PCR targeting the 16S rRNA gene to detect less than 265 cells per liter of water. DNA purification was not required for this level of detection. Initial studies to amplify lysed cells by real time PCR indicated that an incorrect product was made. When purified DNA was used for real time PCR, the correct product was produced from DNA representing as few as 100 cells. This publication can be purchased and downloaded via Pay Per View on Water Intelligence Online - click on the Pay Per View icon below

Use of Novel Techniques to Quantify Phenotypes in Biological Treatment Process

Use of Novel Techniques to Quantify Phenotypes in Biological Treatment Process PDF Author: K. G. Robinson
Publisher: IWA Publishing
ISBN: 1843396971
Category : Science
Languages : en
Pages : 220

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Book Description
This research attempts to evaluate nitrification treatment performance in combined carbon/nitrogen municipal wastewater reactors using traditional physical/chemical methods and modern molecular techniques. Bench scale activated sludge reactors were operated at different SRTs under varying DO levels and temperatures over a 21-month period. Real-time PCR assays were used to determine cell concentrations of total bacterial 16S rDNA, a gross measure of biomass content, the amoA gene, a measure of ammonia-oxidizing bacteria (AOB), and the Nitrospira 16S rDNA gene, a measure of nitrite-oxidizing bacteria (NOB). As expected, gravimetric biomass and total bacterial 16S rDNA levels increased with increasing SRT. Ammonia oxidation rates and N. oligotropha-type AOB concentrations did not follow similar trends with respect to changes in SRT, temperature, and DO nor were they highly correlated. The concentration of available nitrite and SRT were positively correlated with Nitrospira cell densities, while DO concentration and temperature were negatively correlated with NOB levels. The percentage of the total population comprised of AOB and NOB obtained with the real-time PCR assays were compared to predicted values estimated from design equations using typical kinetic parameters. While the percentages of NOB measured using the real-time PCR assay corresponded very well with the predicted values, the measured percentages of AOB were much lower than those estimated from the design equations, suggesting that N. oligotropha-type AOB were not the dominant ammonia-oxidizing species in these reactors. This publication can be purchased and downloaded via Pay Per View on Water Intelligence Online - click on the Pay Per View icon below

Evaluation of Microbial Risk Assessment Techniques and Applications

Evaluation of Microbial Risk Assessment Techniques and Applications PDF Author: J. A. Soller
Publisher: IWA Publishing
ISBN: 184339684X
Category : Science
Languages : en
Pages : 176

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Book Description
This investigation reviewed and evaluated methodologies used for microbial risk assessment with respect to their applicability for reclaimed water applications. The investigation was comprised of five primary components: a comprehensive database of articles, reports and books describing microbial risk assessment methodologies was established and reviewed. Risk assessment techniques and models were identified for estimating the public health risk from exposure to microorganisms via reclaimed water applications. Two models were identified for further evaluation: a static (individual based) and a dynamic (population based). In the third component, the two models were evaluated to differentiate between the conditions under which models predict similar and substantially different estimations of risk. Through numerical simulation, exposure/pathogen combinations were identified when it may be appropriate to use the less complex, static model. Case study risk assessment scenarios demonstrated the model selection process for three realistic, yet hypothetical reclaimed water scenarios.The fourth component presents a constraint analysis for existing reuse regulations. The constraint analysis is carried out by documenting the existing reuse regulations. The constraint analysis is carried out by documenting the existing regs in three states for landscape irrigation and uses that comparison as a starting point to identify how microbial risk assessment may be useful within the context of existing and potential future water reuse regulations. The investigation concludes by identifying criteria for a computer interface that would allow regulatory and/or municipal agencies/utilities to take advantage of the analysis discussed in the report. This publication can also be purchased and downloaded via Pay Per View on Water Intelligence Online - click on the Pay Per View icon below