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OWNER'S MANUAL
Arsenic Facts
Arsenic (abbreviated AS) is a naturally occurring contaminate found in many ground waters. Arsenic is water that has no color, taste or oder. It must be measured by a lab test. Public water utilities must have their water tested for arsenic. You can get the results from your own water utility. If you have your own well, you can have the water tested. The local health department or the state environmental health agency can provide a list of certified labs. The cost is typically $15 to $30. Information about arsenic in water can be found on the internet at the US Environmental Protection Agency website: www.epa.gov/safewater/arsenic.html.
There are two forms of arsenic: pentavalent arsenic (also called As(V), As(+5), and arsenate) and trivalent arsenic (also called As(III), As(+3), and arsenite). In well water, arsenic may be pentavalent, trivalent, or a combina- tion of both. Special sampling procedures are needed for a lab to determine what type and how much of each type of arsenic is in the water. Check with the labs in your area to see if they can provide this type of service.
Reverse Osmosis (RO) water treatment systems do not remove trivalent ar- senic from water very well. RO systems are very effective at removing pen- tavalent arsenic. A free chlorine residual will rapidly convert trivalent arsenic to pentavalent arsenic. Other water treatment chemicals such as ozone and potassium permanganate will also change trivalent arsenic to pentavalent arsenic. A combined chlorine residual (also called chloramine) may not con- vert all the trivalent arsenic. If you get your water from a public water utility, contact the utility to find out if free chlorine or combined chlorine is used in the water system.
The Nimbus Sierra system is designed to remove pentavalent arsenic. It will not convert trivalent arsenic to pentavalent arsenic. The system was tested in a lab. Under those conditions, the system reduced 0.30 mg/L (ppm) pen- tavalent arsenic to 0.010 mg/L (ppm) (the USEPA standard for drinking water) or less. The performance of the system may be different at your installation. Have the treated water tested for arsenic to check if the system is working properly.
The RO component of the Nimbus Sierra system must be replaced yearly to ensure the system will continue to remove pentavalent arsenic. The compo- nent identification and location where you can purchase this component are listed in this installation manual.
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