Arsenic in Public Water Supplies


The Quansor Monitor for Use at Community Water Systems (CWS)[1]

According to the Environmental Working Group, 113 million Americans consume some level of arsenic in their drinking water[2].  About 85% of American drinking water is processed by community water systems.  There are 60,000 CWS in the US that treat for arsenic[3].

There are three uses of the monitor:

1. Determine arsenic concentrations in the source water prior to processing at the CWS

There are 1.5 million USGS water gauges is the US, positioned upstream from CWS, industrial sites and other nodes in the water use cycle.  They monitor for pH, temperature and are not specific for contaminants.  A Quansor arsenic monitor can be included with the USGS gauge.  The USGS will share costs with the CWS.

 2. Determine the optimal sorbent for use in removing arsenic

For a CWS, a column of arsenic sorbent will cost about $35,000.  One issue is how to determine the optimal sorbent.  That is done by comparing manufacturers’ recommendations together with recommendations of environmental consultants who perform field testing to evaluate competing sorbents, using lab analyses to provide the measurements.

The Quansor approach is to automate the evaluation process, passing the local challenge water across five (5) competing sorbents, with a real-time monitor at the outlet of each column.

The evaluator will (a) determine which sorbents work best for challenge waters in a selected area and (b) use an on-line program to provide an economic analysis for each.  The customer will have access to an objective analysis of what treatment option is best.

This device will be leased by Quansor to environmental engineering firms who provide services to community water systems (CWS) or to localities that have arsenic in local wells.  The device will be connected to the Internet.  Quansor will (a) build a data base that will determine which sorbents work best in varying water parameters and (b) provide results of an optimization model that will specify which sorbents are the most economic for each community.  Quansor will be impartial.

 graph

 

3.  Optimize the efficiency and effectiveness of the arsenic-removing treatment system

A third monitor use is to position one at the outlet of the CWS water treatment process to determine when the sorbent in the treatment column needs replacement. The sorbents cost $35,000 to replace.

From the Arsenic Water Technology Partnership at Sandia National Labs,

“Currently, such determinations rely on inaccurate estimates of arsenic capacity based on secondary indicators such as cumulative flow or model predictions.  Direct measurement of arsenic concentration in the effluent will allow more efficient use of the columns and lead to substantial cost savings.”[4]

The Overall Benefit

A Quansor website will display the economic choices on the Internet for all communities as the data becomes available.  The website will contain interesting graphics that will take the mystery out of complex water issues.[5]

The upshot of all this is that the public will be the winners; the treatment cost for cleaning up arsenic will be minimized whether at the community level or at home.  Some treatment companies will not be pleased to lose out to more efficient competitors but the more efficient will benefit and that’s all to the public good.

This is discussed in terms of arsenic, a huge problem in the US.  This problem once corrected would be a major improvement in American life.  The same procedure can be employed to correct the other contaminant issues.

 

FIELD TESTING

Arsenic monitors will be field tested at CWS in Maine and New Hampshire.  Quansor will probably lease the arsenic monitors to the CWS [for $300/month] following the industry practice set by YSI, a water instrument company that sells pH and TDS monitors.

 

 


[1] CWS is an EPA designation.  CWS is the same as the “public water supply” or the “public water utility”

 

[2] Per the Environmental Working Group, http://www.ewg.org/tap-water/, 113 million Americans are served some level of arsenic in their drinking water.

[3] There are 113 million Americans with arsenic in their tap water which is 37% of the US population of 305 million.  Per the EPA, there are 170,000 community water

systems (CWS) in the US serving 85% of the households.  Thus, there are about 63,000 CWS that treat for arsenic (170,000 x 0.37).

 

[4] Letter to the Water Environment Research Foundation, Subject: Paul L. Busch Award Endorsement Letter” dated May 22, 2008 from Malcolm Siegel, PhD, Project

Manager for the Arsenic Water Technology Partnership (AWTP) at Sandia National Laboratories.

 

[5] Quansor’s software services are provided by Wendell Wilson Consulting, Richmond, KY.  They provide the website for the Discovery Channel and another scientific

channel.  They do excellent work.