What UV system?

[NutmegCT]

Merry Christmas to all! I'd appreciate your thoughts on my question about adding an undercounter UV system.

I have a 200 foot well, drilled in 1979. Latest water quality test result by Univ. of Connecticut shows E. coli not present; total coliform Present. Additional results:

Chloride 2.4 mg/L
Nitrite <.2
Nitrate <.2
Sulfate 16 mg/L

Mercury <.0005 mg/L
Iron <.04
Manganese <.04
Calcium 23 mg/L
Calcium Hardness 58 mg/L
Magnesium 1.4 mg/L
Sodium 9.8 mg/L
Total Hardness 63 mg/L

Alkalinity 64 mg/L
pH 8.1

color, apparent <2
Color, true <= apparent color
turbidity 0.21 NTU

Ammonia as N <.05 mg/L
odor, intensity 0

arsenic, barium, cadmium, chromium, copper, lead, ickel, selenium, silver, zinc all <.001; uranium 1.2 ug/L

I have a whole house .5 micron sediment filter, which I change every six months.

From the above results, I'd think I only need an undercounter UV system on my drinking water supply. But I'm sure no expert! I think my well provides excellent water, which flows at 1.5 gal/min. after going through the whole house sediment filter; sediment filter is at the point of entry into the house.

What are your thoughts on just adding an undercounter UV system at the kitchen sink?

Thanks.
Tom M.

 

[Reach4]

There is a good chance that the coliform was in the test sample only because you did not sterilize the faucet.

If you care about the coliform test results, care needs to be taken in sampling. http://www.ugra.org/pdfs/SamplingHandout.pdf is one description of a method to avoid contaminating the sample.

I would sanitize the well and plumbing when the weather is decent. https://terrylove.com/forums/index....izing-extra-attention-to-4-inch-casing.65845/ is my write-up.

I am not a pro.

 

[Sponsor]

 

[Mialynette2003]

Uv does not kill. It only scrambles the DNA so bacteria can not reproduce. It depends on the intensity of the light so if the quartz sleeve gets dirty, the intensity is less making it possible for the bacteria to live. Chlorine on the other hand kills and you can measure the residual in the water. As long as you have residual, you have added enough to kill all the bacteria. Food for thought.

 

[NutmegCT]

Thanks gentlemen. I'd read about the UV and DNA scrambling, but still don't really understand the implication.

If the DNA is scrambled, and the bacteria won't reproduce, doesn't that protect another organism from infection? (such as developing a bacterial infection). It would seem that if the bacteria is, in effect, "sterile", then a host organism (like me) wouldn't develop an infection (illness) from it.

I certainly know that chlorine would be a better path, but I know of no whole-house chlorinating systems that I can afford, especially with my old (1826) house with a wet basement, which can flood during hurricanes, heavy rains, or snow melt. An undersink UV system would be protected from those basement problems - and I assume would be a heck of a lot less expensive.

Thanks.
Tom M.

 

[Reach4]

If the DNA is scrambled, and the bacteria won't reproduce, doesn't that protect another organism from infection?

I think so. What about a good under-sink reverse osmosis filter? Bacterial cannot pass through those.

 

[ditttohead]

If bacteria is shown as present an approved reduction method should be used like UV. When an RO is sitting and not in use, osmosis occurs so many things can pass through the membrane. Personally I would go with a simple and inexpensive UV with a submicron absolute filter that is certfied for cyst...
Here are a few examples
https://view.publitas.com/impact-water-products/2018-catalog-final/page/270-271
https://view.publitas.com/impact-water-products/2018-catalog-final/page/222-223

 

[NutmegCT]

Thanks very much for the recommendations.

Is there a formula or table somewhere to help me figure the size (length, wattage, etc.) I'd need for my UV treatment need? Under sink installation, 1.5 gpm cold water flow, etc.?

I've already got a whole house 5 micron filter.

Thanks.
Tom M.

If bacteria is shown as present an approved reduction method should be used like UV. When an RO is sitting and not in use, osmosis occurs so many things can pass through the membrane. Personally I would go with a simple and inexpensive UV with a submicron absolute filter that is certfied for cyst...
Here are a few examples
https://view.publitas.com/impact-water-products/2018-catalog-final/page/270-271
https://view.publitas.com/impact-water-products/2018-catalog-final/page/222-223

 

[ditttohead]

Check out the catalog, it has a UV 101 page, fairly well written and informative for a single page article. I am in Texas and on my way to Central America for the week so I cant link you to the exact page, maybe someone else can.

UV... very complex and a single page does not do it justice. Actuallly, even a 4-8 hour seminar barely scrapes the surface but in general if you do a 1 GPM rated uv for 1 GPM for clean clear water, you will be ok. a larger system is needed for water of lower quality. Read UV 101, let me know if this helps.