E. coli, onion rust and potable water
In reference to “WQA on HPC with MAC upsets reader” (Letters, WC&P, July 2000), for many decades, the absence of E. coli in water presumed freedom of warm-blooded animal waste and associated pathogenic organisms.
However, the absence of E. coli does not mean the water is safe to use or potable. Pseudomonas is one of the widest spread microorganisms in the ground, water and air. At one time “Onion Rust” [Puccinia allii] was sprayed into air ducts to determine airflow. Orange-colored colonies indicated volume and flow throughout the system. This practice was continued until hospitals found individuals died of Onion Rust.
Total bacteria tests should be less than 10-50 colony-forming units per milliliter (cfu/ml) for the water to be potable. Test too-numerous-to-count (TNTC) results are unacceptable.
Activated carbon is normally used to remove taste and odors (chlorine). The removal of chlorine will allow bacteria to grow and reproduce. Many municipalities are operating at higher pH levels. At pH levels above 7.5 or 8.0, chlorination is less effective, particularly over 9.0. The water pH should not exceed 7.0 for good disinfection with chlorine.
With 9- or 12-inch activated charcoal backwashed carbon filters which are backwashed at least two or three times a week, can have TNTC organic growth level within three months. I recommend changing cartridge filters at least once a month. The growth cycle is a matter of temperature and time. Volume and load have little effect on life expectancy of activated charcoal. As long as the charcoal is physically present, it will eliminate chlorine. Charcoal will selectively remove organic compounds. Short chain organics like phenols will replace larger chain organics that it is removing. When the charcoal is changed, the system downstream of the filter should be disinfected.
If you have any questions, please do not hesitate to call me.
Victor H. Fiscus, Sales & Service
AAqua Associates Ltd.
Bethel Park, Pa.
Fast and loose with chlorine
I read with some concern a letter in your October 2000 publication “Chlorine taste in your drinking water?” Some of my concern is because the letter references an article I produced in your June 2000 issue (“Chlorine: History and Role in the Great Debate for Water Disinfection,” p. 74).
If Mr. Grage read my work, he did not understand what it was trying to say. Statements like “the complete elimination of deadly diseases such as cholera, typhoid and others is now taken for granted thanks to the effectiveness of chlorinated waters” are reckless with the facts. If we have achieved such a milestone, it defies my research on the subject.
“What goes into the ground today, you’ll drink tomorrow” is most certainly true of organo-chlorines but not of most microorganisms. Statements like “chlorine produces bacteria free water” and others mentioned play loose and fast with the truth. Playing fast and loose with the truth is as potentially dangerous as the combined effects of tequila and handguns.
In my article, I clearly exclaim the benefits of chlorine as a water disinfectant. I explore in some detail the cost benefits as well. But I state quite clearly that even though chlorination is the cheapest and easiest method of disinfection, it’s not available in many areas around the globe and misapplied in many areas where it is available. More than 5,000 people died in South America in the 1990s because of waterborne disease [cholera] that would hardly stand with any use of the word “elimination.”
Wm. S. Siegmund, CWS-V
Pure Water Works Inc.
Traverse City, Mich.
USGS arsenic map flawed?
I happened to see your article in WC&P (M. Bayati & M. Stouffer, “Impact of Proposed New Arsenic Standards on POU Carbon Filtration,” July 2000, p. 84) concerning arsenic. Unfortunately, my copy is a very poor quality fax from someone else.
However, I would like to point out some possible problems with the map [used] from the U.S. Geological Survey (USGS) Arsenic in Groundwater FS-063-00 publication. It would appear the map in your article shows one county in Florida—Putnam—with high arsenic. At least, it appears to stand out in the faxed copy of your article.
There were no wells sampled in Putnam County, according to the USGS web data. The USGS is looking into my email comments of June 20, regarding incorrect data being used in their survey. Thus, with the spatial averaging the USGS utilized to produce its map, it would appear they may have lumped counties with and without data in the eastern portion of the United States.
Without a listing from the USGS of the individual county rankings, I think the USGS map is just a “pretty picture.” In any case, it cannot be relied on to furnish accurate information until the USGS fully reviews and documents its methods in producing the map.
St. Johns River