REMOVAL OF ARSENIC IN WATER
While there are serious health threats associated with ingestion of arsenic, there are effective and safe methods for removing arsenic in water. Arsenic in water occurs naturally and is a tasteless, odorless and colorless contaminant. Certain activities that could have left arsenic residuals include apple orchard spraying, coal ash disposal, and use of some pressure treated wood. Many Boxborough homeowners are quite surprised when getting their lab test results back and find they have arsenic in their well water. For detail on potential health affects, see the link at: http://www.who.int/mediacentre/factsheets/fs372/en/
Primary forms of Arsenic in water are Arsenic III and Arsenic V. Many arsenic removal media have low capacities for removing Arsenic III from the water, therefore converting it to Arsenic V (which is easier to remove) is a common approach. Determining the Arsenic III versus Arsenic V ratio in water is critical as this will allow the design and implementation of a water filtration system that will effectively remove it. There are methods to oxidize the Arsenic III and convert it to Arsenic V for ease of removal. While not all towns have detected arsenic in their well water, pockets have been found in Boxborough which elevates the importance of proper testing, follow-up, etc.
WATER TEST & ANALYSIS AND OTHER FACTORS
Having a complete laboratory water test and analysis, including parameters that can negatively impact arsenic removal media, is critical to a well designed, safe water treatment system that will remove the arsenic in water. pH can significantly affect Arsenic media performance along with other competing ions such as Iron, Manganese, Hardness, Vanadium, Sulfate, Phosphate, Silica, Total Dissolved Solids, Suspended Solids and Hydrogen Sulfide. For a full article on this topic which we’ve had published in Water Technology Magazine, go to our publications section and click on the Arsenic removal article at http://h2ocare.com/publications/.
WATER USAGE MONITORING
Determining water usage is also critical to designing an effective removal system that will have the proper capacity. Key information would include well pump size, well pump flow rate, size of the incoming water line, number of residents in the home, the number of bathrooms, space availability for equipment installation, electrical availability and water discharge location or restrictions, among others.
TRACKING WATER USE AFTER SYSTEM INSTALLATION IS IMPORTANT
A couple of key components for consideration when designing a system to remove arsenic in water include:
- Utilizing a meter to track flow rate and total gallons processed is critical to determine the home’s water demand.
- Gallons used readings also assist in uncovering any potential leaks in the home such as running toilets, which will unnecessarily prematurely deplete the arsenic media’s capacity.
LEAD/LAG TANK DESIGNED FOR ADDED SAFETY
Because Arsenic in water is a tasteless, colorless and odorless contaminant, it is particularly important to have two tanks in series in case the first tank is depleted prior to scheduled service with your water treatment company. Service should be scheduled at intervals determined by the water use tracking data accumulated. This combined with appropriate water testing intervals are added safeguards to prevent Arsenic from getting into the treated water entering the home.
To summarize, while finding Arsenic in water may first come as a shock, if you are contemplating buying a home that has Arsenic in the well, you can have a safe, effective system installed to eliminate this problem and provide safe drinking water.