Researchers examine the feasibility of treating hexavalent chromium — the carcinogen made famous by the movie “Erin Brockovich” — with strong base anion exchange (SBA-IX).
Providing large cities with drinking water is never an easy task. Outdated systems can cause problems such as leakages or contaminations.
Levels of a widely used class of industrial chemicals linked with cancer and other health problems — polyfluoroalkyl and perfluoroalkyl substances (PFASs) — exceed federally recommended safety levels in public drinking-water supplies for 6 million people in the United States, according to a new study led by researchers from the Harvard T.H. Chan School of Public Health and the Harvard John A. Paulson School of Engineering and Applied Sciences (SEAS).
Originally built to treat 10 million gallons per day (MGD), the Quail Creek Water Treatment Plant in Washington County, Utah, now has an operational capacity of 60 MGD and a design capacity of 80 MGD.
A chemical company which specializes in Clean-In-Place (CIP) systems, contacted Mazzei to discuss the use of ozone as an alternative to peracetic acid sanitation or heat sterilization at their customers’ plants.
California’s inland communities have been hit hard by four years of drought, lower groundwater levels, and reduced allocations from the State Water Project.
With people flocking to the trendy Texas metropolis, Austin needed a new treatment plant to sustain its growth — but a “sensitive” touch was required to complete the project while protecting the environment.
The Ecomuseum Zoo is home to the most impressive ambassadors of Quebec’s wildlife. All residents of the Ecomuseum Zoo are there for a special reason: orphaned, injured or born under professional human care, each of them could not return to the wild. Hence, they have found a forever home at the zoo.
When the City of Midlothian, Texas, was ready to expand their water treatment plant to accommodate a growing population, they carefully considered and investigated their water disinfection options.
With 100 years of service history, Austin Water has seen enormous change in its 540 square miles of service area. Planning for the next 100 years has city and utility planners considering a diversity of sources, system resilience, and sustainability while being mindful of conservation goals. In the city’s newest water treatment plant, WTP4, Austin Water was able to combine those planning elements into a state‐of‐the‐art treatment plant. The plant, which is located on Lake Travis, is capable of treating 50 million gallons a day (MGD) with the ability to expand to 300 MGD.
Hendersonville Utility District (HUD) serves one of the most populous suburbs of Nashville, Tennessee.
In the 1990s, the City of Wichita, KS, developed a water supply plan that included creating a sustainable water supply through the year 2050. The key component of the plan is recharging the large aquifer that lies under the region with 100 MGD of water from the Little Arkansas River.
First settled in 1836, the City of Berea, Ohio gained acclaim as being the source for dimensioned stone formed from locally quarried sandstone, notably grindstones. The grindstones were shipped to Cleveland by oxcart and, as demand grew, later by a purpose-built railroad to the Big Four Railroad across the Midwest. Now many of the former quarry pits are better known as Baldwin Lake, Wallace Lake and Coe Lake.
The Mazzei Sidestream Venturi Injection – Pipeline Flash Reactor System provides a feasible alternative for dissolution of ozone at the Clark County Water Reclamation District (CCWRD) in Las Vegas, because it allowed for flexibility in basin design to meet geographic site constraints.
The removal of contaminants from public drinking water systems in the US is mandated by the Environmental Protection Agency’s (EPA) National Primary Drinking Water Regulations. These are legally enforceable standards that protect public health by limiting the levels of contaminants in drinking water. Similar regulations are managed by agencies worldwide to protect their citizens from drinking water contamination.
There are a plethora of drinking water contaminant removal technologies that public and private water systems use to comply with the EPA’s drinking water regulations. These include reverse osmosis, membrane, nanofiltration, ultrafiltration, chlorine disinfection, UV disinfection and Ozone-based disinfection practices.
The EPA’s list of drinking water contaminants is organized into six types of contaminants and lists each contaminant along with its Maximum Contaminant Level (MCL), some of the potential health effects from long-term exposure above the MCL and the probable source of the drinking water contaminant.
The six types of contaminants are microorganisms, disinfectants, disinfection byproducts, inorganic chemicals, organic chemicals and radionuclides.
Examples of microbiological, organic contaminants are Cryptosporidium and Giardia lamblia. Both of these microorganic pathogens are found in human or animal fecal waste and cause gastrointestinal illness, such as diarrhea and vomiting.
A common disinfectant used in municipal drinking water treatment to disinfect microorganisms is chlorine. The EPA’s primary drinking water regulations require drinking water treatment plants to maintain a maximum disinfectant residual level (MDRL) for chlorine of 4.0 milligrams per liter (mg/L). Some of the detrimental health effects of chlorine above the MCL are eye irritation and stomach discomfort.
Similarly, byproducts from the chlorine-based disinfection methods used by public water systems to remove contaminants can be contaminants in their own right if not removed from the drinking water prior to it being released into the distribution system. Examples of disinfection byproducts include bromate, chlorite and total trihalomethanes (TTHMs). Not removed from drinking water, these disinfection byproducts can increase risk of cancer and cause central nervous system issues.
Chemical contamination of drinking water can be caused by inorganic chemicals such as arsenic, barium lead, mercury and cadmium or organic chemicals such as benzene, dichloroethane and other carbon-derived compounds. These chemicals get into source water through a variety of natural and industrial processes. Arsenic for example is present in source water through the erosion of natural deposits. Many of the chemical contaminants are derived from industrial wastewater such as discharges from petroleum refineries, steel or pulp mills or the corrosion of asbestos cement water mains or galvanized pipes.
Radium and uranium are examples of radionuclides. Radium 226 and Radium 228 must be removed to a level of 5 picocuries/liter (PCI/L) and Uranium to a level of 30 micrograms/liter (30 ug/L).