[Mr Peanut]

Hello,

This seems like the best sub-forum for this.

Lately I have been helping out with a local watershed management group. Among other things, we have been helping residents to get their well water tested. The question frequently comes up: "What do we do if we have high results for something?" Clearly, the answer is to identify the source and, if possible, correct it or relocate the well. However, this is an agri-intensive area and some things like high nitrate levels are simply part of the aquifer. Treatment by RO or ion exchange is the only option.

The Provincial lab rats, the vendors, and even the manufacturers call these systems "filters". In fact they call everything a filter (from water softeners to UV lights). My dictionary disagrees.

Give me some more ammunition.

Thanks

[clustro]

I am confused. What is your actual question?

What the definition of a "filter" is?

http://dictionary.reference.com/browse/filter

#3 would suggest any device meant for separating the wheat from the chaff would be a "filter", even an advanced oxidation process/UV light assembly.

[Mr Peanut]

I am looking for a reference to use (a reference with a convincing pedigree) that specifically states that softeners, ion exchange systems, RO, etc are not, strictly speaking,  filters (that is, that they should not be referred to as filters). I understand what a filter is. I need a convincing reference. Surprisingly, I have not found anything with Google. Typically, I find that State Environmental Agencies, the EPA, and academic institutions provide useful clarifications on similar issues where there is confusion.

Its not just a rant. When the Provincial Government says to a homeowner with  elevated nitrate in their well water: "you need a filter, call a water treatment company", they do it. The vender comes over and says the filter is going to cost $1600. They hold off and then go to the hardware store and ask "do you sell filters". The store says "yup we got 'em" and sells them a $30 cotton wound filter. It happens frequently.

Why is a industry-specific, respected reference needed? Because, as I said, the entire chain of information (the Provincial laboratory, the vendor, and the manufacturers) are using the term filter here.

[P]

What about getting them to specify what TYPE of filter they require?  The word (as you know all to well) covers a hell of a lot of different types of kit ranging from cotton wool buds, TLC through to SEC chromatographs and ion exchange 'filters' etc... Some of which cost more then others.  I personally don't see the problem with the term 'filter'.  The problem is the under informed not understanding that a filter can be more than just a bit of cotton wool or a sieve. I reckon it's your job to educate them.  Can you give them a lecture entitled "Industrial Filtering systems and their Diversity"  or something? 

[Mr Peanut]

Thanks,

Yes, public information is the key. I am finishing an eight page narrative for residents on several aspects of water quality for private wells. One section is on treatment strategies. The paragraph on nitrate treatment is provided below. Because we have an entire sector (government, manufacturers, etc.) using the term filter for everything I have adopted the philosophy that changing the use of an entrenched term is not a productive task. Originally, in an earlier draft, I made a stronger statement than the one that appears in the narrative below. I stated that the term filter was misused. Whenever I make a statement that counters convention I require myself to cite a reliable reference. Not being able to find one, I softened the language.


portion of current draft:

3.3 Dealing With Problems
If testing shows a drinking water well is contaminated then certain questions follow. The questions depend on the contaminants found. Is it a shallow well? Where is the well located? What activities are going on around the well (septic system, agriculture, etc)? Frequently problems can be corrected by well maintenance. Sometimes they cannot. When the problems cannot be corrected, the water can often be treated before use. It is always best to remove the contamination source or relocate the well rather than treat the water. Once again, because it is very important, treatment should only be done when corrective measures fail or are impractical. Why? Because treatment systems require ongoing maintenance. If they are not regularly serviced they not only can fail to do their job, they can cause more harm than good.
When it is a nearby septic system causing the problem, the problem can usually be corrected. Many other causes are harder to correct because they impact the entire aquifer. If the well is a shallow well then the problem may be solved by upgrading to a modern deep well. The whole process can be overwhelming for the resident. Our role as watershed managers is to help with interpreting problems and to recommend solutions.
Nitrate
When corrective measures fail, there are two primary ways to treat elevated nitrates in the water: reverse osmosis and ion exchange (each has its advantages and shortcomings). There are whole house systems and “under the sink” units. The whole house system is by far the best approach. The reverse osmosis systems should be available for under $1200 installed. Standard Water softeners, boiling the water, and simple filters will not remove nitrates. Standard water softeners remove calcium, magnesium, iron and manganese. There are some more expensive softeners that have additional capabilities for nitrate removal. Boiling kills bacteria. Strictly speaking, filters remove particles, but treatment systems are often called filters, even by manufacturers. So, when you hear the term filter be sure to get a detailed specification for the particular system being discussed. All treatment systems require regular maintenance. If they are not maintained they will be ineffective and, perhaps, dangerous.