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  • Cool Tool The Drinking Water Treatability Database
    new reference tool has you covered or at least soon will The recently revamped Drinking Water Treatability Database TDB is set to include more than 200 contaminants both regulated and unregulated with detailed information on what they are where they come from and how to get rid of them Currently the database covers 66 contaminants but its breadth is nonetheless impressive The site compiles information from thousands of sources providing general overviews properties and fate and transport characteristics for each pollutant Perhaps most pertinent and useful to operators and engineers is the information on efficacy of treatment i e which processes can handle which contaminants It allows compare and contrast decision making that was never so easily accessed There are two main sections or ways to navigate the site Find a Contaminant In this section you can find your un desired contaminant by name browse alphabetically or segment by classification chemical microbial or radiological Note that there are also Quick Links for further research regulatory requirements health impacts analytical methods historical monitoring data and a link to EPA s Integrated Risk Information System IRIS The Treatment Processes tab reveals the methods suitable for remediating the contaminant in question These are processes that are most commonly employed and those less commonly employed but known to be effective according to the EPA Find a Treatment Process To discover the range of contaminants that each process can treat it may be more useful to search by technology Twenty eight processes are currently covered shown below but the section will be expanded with time Here valuable process parameters such as dosing loading rates and contact times as well as water quality parameters such as temperature pH and turbidity can be explored There is much more to the TDB and much more yet to come

    Original URL path: http://www.wateronline.com/doc/cool-tool-the-drinking-water-treatability-database-0001 (2016-02-14)
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  • Zero Liquid Discharge Project Turns Treatment Byproduct Into Drinking Water
    four trains is offline for cleaning maintenance or repair The UF elements are cleaned through permeate backwash chemically enhanced backwash and clean in place CIP operations The chemically enhanced backwash uses sulfuric acid sodium hydroxide or sodium hypochlorite CIP operations use citric acid sodium hydroxide or sodium hypochlorite The UF system is housed in a pre engineered metal building designed to accommodate additional UF membranes and other components to allow for a future expansion of the ZLD process to 1 8 MGD After the softened water is filtered by the UF membranes the UF filtrate is conveyed to the UF filtrate and backwash tanks The filtrate from the UF filtrate and backwash tanks is disinfected using free chlorine before blending with the combined permeate and raw water bypass water directly upstream of the existing ground storage tank and converting to chloramines for final disinfection In addition to the main ZLD process stream two other process streams are associated with the concentrate ZLD process a solids stream and a recycle stream The system recovers over 99 3 percent of the concentrate This occurs by collecting the five recycle recovery streams and combining them in the equalization tank where they are recycled to the head of the ZLD process The recycle streams include solids laden softened water from the UF feed tank UF pretreatment strainer backwash UF neutralized chemically enhanced backwash water gravity sludge thickener supernatant and belt filter press filtrate The recovery and recirculation of the various streams within the concentrate ZLD process are imperative for successful implementation The ZLD system was designed to produce lime sludge with approximately 50 percent dry solids Sludge removed from the solids contact clarifiers is transferred to a gravity sludge thickener From there solids removed from the gravity sludge thickener are pumped to the solids handling and dewatering system via rotary lobe pumps Sludge is dewatered with two belt filter presses which allows 100 percent redundancy The dewatered solids are hauled from WTP No 2 by the city s contract hauler where they are mixed with recycled concrete for dust control and act as a binder in the production of a paver base Project Challenges Recycle Streams One of the project s biggest challenges was handling all the recycle streams needed to achieve 99 3 percent recovery Because of each stream s varying volume duration and frequency an equalization tank with a capacity of approximately 80 000 gallons was designed and sized to provide ample capacity for the flows In addition to providing the requisite storage for the recycle flows the equalization tank was also fitted with a mixing system that includes jet type mixing eductors and a pumping system to keep solids suspended in the tank Three recycle pumps for the equalization tank transfer the various recycle flows back to the head of the ZLD process directly upstream of the solids contact clarifiers where the flows are mixed with the influent concentrate Even with the equalization tank s fairly large capacity flow control of

    Original URL path: http://www.wateronline.com/doc/zero-liquid-discharge-project-turns-treatment-byproduct-into-drinking-water-0001 (2016-02-14)
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  • Keep Austin Sustainable The Unique Case Of Water Treatment Plant No 4
    allowed by the permit from the U S Army Corps of Engineers and the water quality restrictions mandated by the Lower Colorado River Authority the project explored an alternative method to the original design To find an economical and feasible alternative method the CMAR and design team collaborated on constructability of the foundation during the design process In addition the CMAR used a unique approach to value engineering asking contract bidders for additional value engineering ideas Through this process the project eliminated all dredging by employing a drilled or driven pile foundation to support the intake in lieu of the original design Another benefit of substituting prefabricated steel frames used by the driven pile method for the original reinforced concrete frames to support the intake was that it cut by 90 percent the amount of time divers had to be in 150 feet of water in Lake Travis Addressing Environmental Concerns The design and construction of WTP4 including its tunneling components needed to address several environmental factors In fact the initial water treatment plant was set to break ground in 1984 until economic and environmental concerns delayed construction Once the current site of WTP4 was deemed acceptable from economic and environmental standpoints the city of Austin was able to move forward with its plans Completed filter building at WTP4 More than 12 potential sites were evaluated prior to finding this site as having the least negative effect on the environment Criteria included the impact on migrating birds karst invertebrates and vegetation as well as considerations for drainage grading requirements elevation and pumping requirements and alignment of the tunnels built to distribute water from the site Before breaking ground on the project Austin Water Utility and the city of Austin s Watershed Protection Department developed an environmental commissioning plan to guide the project in minimizing environmental impact and protecting the nearby environmental resources sensitive species and their habitat The plan outlined a process that integrates environmental review and oversight of the project to meet the environmental goals beyond typical federal state and local regulatory requirements The process specifically included an ongoing audit with recurring meetings reviews oversight inspection permitting and other tasks The process required a collaboration with the city s project team environmental commissioning team and all contractors working closely together on design and construction methods For the JTM tunnel a key challenge was passing under the Balcones Canyonlands Preserve a system of habitat preserves created to protect eight federally listed endangered species six karst invertebrates and two bird species and a threatened salamander known as the Jollyville Plateau salamander The tunnel was to be built in the Glen Rose formation which was made up of three limestone units Edwards Walnut and Glen Rose The environmental commissioning plan and project team collaboration resulted in a balanced decision making process for vetting the project design Through this process it was decided to shift the JTM tunnel s access shafts to the perimeter of the Balcones Canyonlands Preserve to avoid disturbing that

    Original URL path: http://www.wateronline.com/doc/keep-austin-sustainable-the-unique-case-of-water-treatment-plant-no-0001 (2016-02-14)
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  • Thinking About NDMA (N‐Nitrosodimethylamine) In Drinking Water
    were developed following best practices for risk communication as employed by the Centers for Disease Control and Prevention CDC What follows is WRF s core message sheet covering NDMA N Nitrosodimethylamine The United States has some of the safest public water supplies in the world Our drinking water is treated and monitored to assure that the water being delivered is safe for consumption While our water is safe drinking water quality and management is understandably complicated Small traces of naturally occurring or human made substances can sometimes find their way into the tap water One such substance is N nitrosodimethylamine or NDMA What is NDMA NDMA is an organic chemical that can mix with water and is defined as both toxic and carcinogenic NDMA is sometimes formed when water is disinfected with chloramines Where does NDMA come from NDMA can occur in water air and soil as a result of chemical reactions with naturally occurring substances NDMA also is produced when chloramines a disinfectant react with compounds in water and thus it is an unintended disinfection byproduct at some water treatment plants that ends up in the drinking water It is also found in foods such as beer smoked and cured meats cheese and in cosmetics rocket fuel solvents and lubricants What are the concerns about NDMA in drinking water According to the World Health Organization NDMA has been occasionally measured in drinking water but typically at low concentrations that are unlikely to affect our health i The amount of NDMA in some food such as beer cheese and hotdogs is found in far greater concentrations than in drinking water The primary health concern related to NDMA exposure is its potential to cause cancer NDMA is also considered to have moderate to high toxicity especially to the liver People with liver or renal disease and alcoholics have been identified as potentially more sensitive populations ii There are no established federal standards for acceptable levels of NDMA in drinking water What solutions exist for removing or reducing NDMA from water NDMA can be detected in water using a variety of methods The most common method for removing NDMA is ultraviolet UV light and biological degradation In addition water is sometimes treated to remove the chemicals that may form NDMA called NDMA precursors iii Source of information This information is based on detailed technical information prepared by Dr Shane Snyder Dr Snyder is a Professor of Chemical Environmental Engineering and holds joint appointments in the College of Agriculture and School of Public Health at the University of Arizona He also co directs the Arizona Laboratory for Emerging Contaminants ALEC and the Water Energy Sustainable Technology WEST Center For nearly 20 years Dr Snyder s research has focused on the identification fate and health relevance of emerging water pollutants Dr Snyder has been invited to brief the Congress of the United States on three occasions on emerging issues in water quality He has served on several US EPA expert panels and is currently

    Original URL path: http://www.wateronline.com/doc/thinking-about-ndma-n-nitrosodimethylamine-in-drinking-water-0001 (2016-02-14)
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  • Thinking About Medicines And Personal Care Products In Drinking Water
    on the body i Examples of medicines and personal care products detected in water include antimicrobial materials found in toothpastes and hand soaps fragrances prescription medicines bug sprays and sunscreen Concentrations of these substances detected in water are typically very small ii and are currently not regulated at the federal level in the United States How do medicines and personal care products enter the water system Examples as to how these substances enter wastewater include excretion after ingestion disposal of unused medicines in sinks or toilets or personal care products washed from our hair and skin Depending on the type of treatment some of these can remain even after the wastewater is treated Medicines also may be present in run off water from livestock operations dairies poultry farms and aquaculture facilities and may be present in discharges from pharmaceutical manufacturing facilities and hospitals iii The treated wastewater and the runoff can enter streams or groundwater that are a source of drinking water supply Of course minute amounts of these substances also enter rivers and streams that are used as a source of drinking water when people who are using products such as sunscreens and skin creams swim or bathe in the water What are the concerns about medicines and personal care products in water A great deal is known about the physiological effects of medicines for target populations in light of the rigorous process by which they are developed and approved The degree to which a person might be exposed through drinking water would be very small in comparison to the dose one would normally expect to receive by taking medicine or applying personal care products directly to the body In other words if a person wanted a therapeutic dose of a medicine such as to cure headache pain you would need to drink on the order of 100 000 000 glasses of water to obtain a therapeutic dose At this time no definitive links have been established between medicines and personal care product exposure through drinking water and risks to human health iv and there is no established federal regulation Nevertheless research and investigations continue by the government and water treatment agencies in the interest of safety What treatment approaches exist for medicines and personal care products in water Medicines and personal care products can be removed or reduced through advanced treatment technologies However regulatory bodies have not found any evidence to support requiring additional or specialized treatment to remove them from drinking water v Proper disposal of unused medications land use management to prevent runoff into streams and rivers and other activities to protect our sources of drinking water will help Source of Information This information is based on detailed technical information prepared by Dr Shane Snyder Dr Snyder is a Professor of Chemical Environmental Engineering and holds joint appointments in the College of Agriculture and School of Public Health at the University of Arizona He also co directs the Arizona Laboratory for Emerging Contaminants ALEC and the

    Original URL path: http://www.wateronline.com/doc/thinking-about-medicines-and-personal-care-products-in-drinking-water-0001 (2016-02-14)
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  • Thinking About Chromium in Drinking Water
    is a naturally occurring metal common in the earth s crust There are multiple forms of chromium i and one form called chromium 3 is actually a required nutrient for human health in the right amount ii Chromium in some forms can be toxic at certain doses such as chromium 6 which is also known as hexavalent chromium Where does chromium in drinking water come from Naturally occurring levels of chromium in water could come from rocks plants or soil iii and are usually at levels well below the federal standard for drinking water However human activities such as industrial processes can lead to higher levels of chromium in drinking water iv Chromium 6 compounds are used widely in industrial applications like steel production textile dye production wood preserving and leather tanning Why is chromium in drinking water a concern Concern has been raised about the potential hazards related to ingestion of chromium 6 in drinking water because of a 2008 animal study that suggested chromium 6 may be a human carcinogen if ingested It is a known human carcinogen when inhaled the Environmental Protection Agency EPA the federal regulatory agency for safe drinking water is currently investigating whether it is also a human carcinogen when ingested This investigation will aid in determining whether a new drinking water standard is needed for chromium 6 versus the existing regulation for total chromium v Federal drinking water standards currently limit hexavalent chromium in drinking water by limiting the total amount of chromium that can be in water What solutions exist for chromium Chromium is easily detected in water even in extremely low concentrations 0 000 000 001 Treatment technologies exist to reduce or remove chromium from drinking water water providers manage hexavalent chromium levels by controlling total chromium levels vivii Many but not all home water filters can remove chromium when operated and maintained correctly viii Bottled water also must meet the Food and Drug Administration FDA standard for chromium The EPA has provided guidance to public water systems for monitoring chromium so that they can assess existing water treatment s effectiveness Source of information This information is based on detailed technical information prepared by Dr Shane Snyder Dr Snyder is a Professor of Chemical Environmental Engineering and holds joint appointments in the College of Agriculture and School of Public Health at the University of Arizona He also co directs the Arizona Laboratory for Emerging Contaminants ALEC and the Water Energy Sustainable Technology WEST Center For nearly 20 years Dr Snyder s research has focused on the identification fate and health relevance of emerging water pollutants Dr Snyder has been invited to brief the Congress of the United States on three occasions on emerging issues in water quality He has served on several US EPA expert panels and is currently a member of the EPA s Science Advisory Board drinking water committee He was recently appointed to the World Health Organization s Drinking Water Advisory Panel i US EPA 2013a Basic Information

    Original URL path: http://www.wateronline.com/doc/thinking-about-chromium-in-drinking-water-0001 (2016-02-14)
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  • North Carolina Treatment Plant Eliminates Taste And Odor Issues With Ozonation
    and Metering Asset Management Consumer Outreach Funding Labor Resiliency SCADA Automation Source Water All Source Water Contamination Desalination Water Scarcity Water Reuse Regulations and Legislation Providers YSI a Xylem brand Hach Company Schneider Electric Neptune Technology Group Inc Evoqua Water Technologies Veolia Water Solutions Technologies ABB Measurement Products Aclara Jacobi Carbons Endress Hauser Inc KROHNE Inc Kaeser Compressors Inc Emerson Process Management Rosemount Analytical Degremont Technologies Brentwood Industries View All Providers Case Study March 9 2015 North Carolina Treatment Plant Eliminates Taste And Odor Issues With Ozonation Source WEDECO A Xylem Brand Enactment of the Long Term 2 Enhanced Surface Water Treatment Rule and the Stage 2 Disinfectant Disinfection Byproduct Rule D DBPR will require both large and small drinking water utilities to reduce total organic carbon TOC Cryptosporidium and disinfection byproducts DBPs in the treated drinking water distributed to the public Ozonation has helped prepare a North Carolina Water Treatment Plant WTP to comply with these federal drinking water regulations and overcome long standing taste and odor problems of its raw water drawn from the B Everett Jordan Lake a nearly 14 000 acre flood control reservoir Read the full case study to learn how WEDECO A Xylem Brand

    Original URL path: http://www.wateronline.com/doc/north-carolina-treatment-plant-eliminates-taste-and-odor-issues-with-ozonation-0001 (2016-02-14)
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  • Disinfection Performance Testing Of High-Efficiency Ultraviolet Water Treatment Chamber
    Technologies ABB Measurement Products Aclara Jacobi Carbons Endress Hauser Inc KROHNE Inc Kaeser Compressors Inc Emerson Process Management Rosemount Analytical Degremont Technologies Brentwood Industries View All Providers White Paper April 16 2014 Disinfection Performance Testing Of High Efficiency Ultraviolet Water Treatment Chamber Source NeoTech Aqua Solutions Inc By J R Cooper Ph D and Gwynne Cavender NeoTech Aqua Solutions Inc When introducing a disinfection product which incorporates new technology it is essential that the methods and testing used to quantify the performance of those systems follow protocols which are technically sound and which are accepted by the scientific and technical community within the industry These protocols must be applied precisely and rigorously in order to ensure accurate repeatable results The data generated from experiments following these protocols must be carefully analyzed using proper statistical approaches These analyses must account for variances due to changes in the product s performance as it ages tolerances of measurement equipment and the natural uncertainties associated with the dose response characteristics of microorganisms All of these items must be properly addressed for the rating of the product to be accurately determined This paper describes the methodology used to verify the rated performance of NeoTech Aqua s D series of ultraviolet reactors for water purification Also included is a description of the protocol which was followed for testing the units a description of the equipment used for testing the results obtained during the water disinfection characterization tests and a description of the method for determining the rating of the reactors from the data collected The information in the sections below details how the experiments and analysis of the results performed address the requirements for an accurate product rating This is the second in a series of three white papers describing the design and performance of the

    Original URL path: http://www.wateronline.com/doc/disinfection-performance-testing-of-high-efficiency-ultraviolet-water-treatment-chamber-0001 (2016-02-14)
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