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Water-On-Wheels (WOW) Mobile Emergency Water Treatment System Cart - User Manual
Daniels, K., A. Hall, R. Dever, J. Goodrich, AND J. Hall. Water-On-Wheels (WOW) Mobile Emergency Water Treatment System Cart - User Manual. U.S. Department of Homeland Security, Washington, DC, EPA/600/R-20/178, 2020.
Following a natural disaster, communities need access to clean water not only for drinking but also for cooking, cleaning, and medical triage. If the water system is contaminated, water treatment will be needed. Similarly, mitigation and recovery following a man-made incident or an accident could require water treatment.Not all the water being treated needs to be drinking water quality. In some longer-term recovery efforts, contaminated stormwater or wash water from building decontamination activities only need to be treated to levels safe for disposal to the wastewater treatment plants or back to the environment. Mobile treatment of the highly contaminated water can significantly reduce the volume of water to be transported, and reduce the liability and cost of transporting and disposing of a hazardous waste. Most emergency water treatment systems are large and expensive tractor-trailer mounted systems. They can be complicated to operate and maintain (high pressures and concentrated wastes) given their use of reverse osmosis water treatment technology. An emergency water treatment system could be designed and built so the sequence of treatments can be configured on-site to treat a broad spectrum of contaminants without using unnecessary and costly unit processes, and without producing large amounts of contaminated waste. The broad spectrum of potential contaminants includes chemical, biological and radionuclide contaminants. Rather than a treatment system, bottled water is typically the first responder’s choice when responding to an incident. However, long-term dependence on bottled water creates a large solid waste disposal problem and, often times, large vehicles transporting bottled water are unable to get to affected locations because of road debris and damage. In large or extended recoveries, bottled water use for bathing, sanitation, and other non-potable purposes is impractical. However, bottled water could be used in conjunction with an inexpensive and versatile mobile emergency water treatment system providing water for non-potable water applications such as toilet flushing. Based on these considerations, through a cooperative research agreement, a list of capabilities needed for a mobile emergency water system was developed and a fully functional device was fabricated and challenged. This document provides a User Manual for the set-up, operation, cleaning, and storage of the WOW Cart.
Treatment Train: •Up to 10 gallons per minute •Pre-filtration to reduce turbidity and improve disinfection •Two media filtration/adsorption tanks for targeted chemical or radiological contaminant removal (e.g. Granular Activated Carbon or Ion Exchange) •UV LED for additional microbial inactivation •On-site chlorine gas and bleach generation for disinfection •Ability to add or subtract treatment processes in the field Ability to re-circulate treated water to increase disinfection Power Supplies: •Dual Fuel Generator (propane, diesel) •110v AC •12v DC deep cell marine battery w/solar pane lrecharge Mobility: •Weighs less than 500 pounds •Fits in back of pick-up truck •2-person transport Learning from both the field challenge and Hurricane Maria experience, the final version of the WOW Cart was challenged at the Test & Evaluation Facility with secondary wastewater and subsequently tested again at the Water Security Test Bed against lagoon water contaminated with diesel fuel and Escherichia coli. The WOW Cart successfully removed 4 to 6 logs of E. coli and total coliforms, respectively, to non-detection levels from the contaminated lagoon simultaneously with diesel fuel components. Diesel fuel components were removed to below detection levels, which made the water safe to drink. Results did reveal that extremely dirty water (turbidity >120 NTU) could foul the chemical water treatment process prematurely and prevent adequate supplies of treated water from being available.