Turbidity, metals, TDS -- What are my options?

[BrownCow]

Hi. Am building house. Well water. Well is ready to go, flushed and disinfected and ready to go online. Had water tested and here are the parts of the report that have me scratching my head as how to proceed:

Aluminum: 1.3 mg/l
Iron: .99 mg/l
Total dissolved solids: 550
Turbidity Units: 42

Hardness is shown as 15 MCL which converts to .88 gpg
PH 7.6
Sodium 210 mg/l

What would be the best filter solution? Are there any of the above that I should not worry much about? Since this is new construction, I have the option of a whole-house system if that would be the best way to go. Location is very remote.

Thanks for any help with this.

[Andy CWS]

At less than 1 grain per gallon and less than 0.2ppm iron, and a pH of 7.6, your water is actually pretty good!!! I am kind of curious how you can have naturally soft water and still have neutral pH. Do you live on the East Coast?

550 ppm TDS is quite high considering the low hardness and iron; perhaps sodium? How deep is your well? How long after chlorination was the water tested (how many gallons had passed?)?

Your water is extremely turbide, though. This can be caused by tannins, colloidal particles, or chemical intrusions. USEPA sets 1 NTU as the maximum limit, so you have a long way to go.

First determine what is causing the cloudiness of the water before a solution can be recommended. Possible an ultrafiltration membrane may be suggested.


Andy Christensen, CWS-II

[BrownCow]

Thanks for quick reply. I'm glad I'm not the only one scratching my head.

Well is 640 feet deep, water at 189 ft., through sandstone and grey shale, low production 3-5 gal/min, at approx 6500 ft. elevation, in mountains of central New Mexico. The driller went so deep after reaching water at 189 ft. to get the best production possible. I'm thinking it may just be a muddy aquifer? Most water in these parts is alkaline.

Not sure how many gallons passed since chlorination. I had the builder run out the well after the chlorination. Told him to run it out a couple of hours, but don't know exactly. Maybe I should run it out again for a few hours?

Water will be pumped from well to 1500 gal storage tank, then to house. Would ultrafiltration membrane be whole house? Between storage tank and house? Or at inlet to house? Would solids settle while in storage tank?

Thanks again for any suggestions.

[Andy CWS]

You're welcome.

Letting the water run would be the easiest and cheapest solution. That failing, a filtering system would be next.

There is a chance that solids would settle in the storage tank. Does the tank have a drain at the bottom? Is the tank gravity or atmospheric?

If it is atmospheric then you would have booster pump following it. If it is gravity tank, then it would be at a higher elevation than the house, barn, etc.

I don't think your problem is monumental, but getting all the details may save a lot of headaches.

Andy Christensen, CWS-II

[BrownCow]

Hi,

Storage tank is atmospheric, about 20 feet or so from house, pressure pump and tank in house. I'm pretty sure it has a drain at the bottom, but will have to ask builder to check (I'm not living very close to the house site right now).

Sounds like the first step would be to run out the well again. For how long? All day? I know 600 feet is a lot of water to run out a hose.

Thanks again.

[Andy CWS]

Letting it run all day should not hurt anything. You will need to make sure nothing will be flooded, of course.

Let me know how it goes,

Andy Christensen, CWS-II

[BrownCow]

Thanks. Will keep you posted. It may take some time for it to get done, then retested, but I'll be back!

[Gary Slusser]

With .99 ppm of iron, that's enough to cause rust stains and to use equipment to remove it.

You don't say how deep the pump is in the well. If it is not down to say 10-50' off the bottom, you'll have all the water under the pump's inlet as stagnant water with chlorine in it.

So you need to run the well off more but not out of water. You would turn on a hose and let it run for hours watching it for a reduced flow or dirty water that gets dirtier rather than cleaner.

The TDS and such, other than the sodium, are not health related or much of a problem. Meaning those things may not cause enough of a problem to buy equipment to reduce or remove them.

You shouldn't buy much of anything until you use this water for awhile because new wells have a tendency to change the water quality after using them for awhile.

A disposable cartridge filter is not going to reduce or remove the clear water ferrous iron.

[BrownCow]

Thanks, Gary.

If/when I do need a filter, possibly for the iron, will it be difficult to install after the plumbing system is complete? I ask because if I knew I needed something now, I could get the plumber to install it as he finishes the system. Otherwise, I'll have to try to get him to come back out months from now, which might be a problem, given the remote location.

What sort of filters might be suggested, just to give me an idea?

Thanks

[Gary Slusser]

With an atmospheric storage tank, the ferrous iron will convert in the storage tank to ferric iron, rust. Then the tank will be cleaned and drained some, 50-100 gallons once in awhile to rid the rust that will usually sink to the bottom of the tank.

Your concern should be bacteria etc. growing in that tank.

The only type filter you could use would be a disposable cartridge type which you should not use between the pump and the storage tank.

A filter is not going to disinfect the water and a UV light won't work unless you pretreat the water. So chlorination, hydrogen peroxide or ozone would be used. Although I don't like chlorine, especially in a solution feeder with a large retention tank type system, I use it in a no moving parts, non electric erosion pellet chlorinator followed by a 12" x 65" special mixing tank that is equivalent to a 120 gal retention tank, followed by a special carbon in a downflow backwashed filter that will clarify the water (it removes the rust/dirt) and remove the chlorine taste and odor.

Any equipment will go in the plumbing after the storage tank. So all that is needed is to cut the water line and plumb the line from the tank to the equipment and then back to the side of the pipe that goes to the house. That usually is/can be done after the plumber is finished installing the house plumbing as long as there is space available for the equipment. The space is usually along the wall about 6', less if no softener is used and then out from the wall about 24" with about 6' of head room. Or outside by the storage tank and if outside, you should have some type of roof over the equipment if possible but it's ok without a roof.

[BrownCow]

A little confusion here.

The storage tank is poly, not metal.,

The line from storage tank to garage is buried, then into garage freeze-proof utility closet to pressure tank. Booster pump also is in the garage. Space in the garage is very limited.

Why should I worry about bacteria in the storage tank? Where we are now, with gravity-fed metal storage tanks, we don't worry about bacteria.

[Gary Slusser]

Ferrous iron is soluble, meaning it is dissolved in the water. When it is oxidized by air/oxygen, it converts to ferric iron which is rust particles.

So it does not matter whether if the tank material is plastic or galvanized.

If you don't have space for equipment..... what do you plan to do then?

Air contains bacteria, and then there are flying and crawling insects, mold and spores etc. can usually get into atmospheric tanks and what happens to stagnant water over time?

[BrownCow]

It's a closed tank, closed system. So I still don't see where I have to worry about bacteria. We've never had a problem with any of our storage tanks/water systems -- all closed tanks, buried water lines, submersible pumps.

Periodically draining the rust out of the bottom of the tank will be easy enough.

[Gary Slusser]

All I know is that all atmospheric tanks must allow air in and out as water is added and taken out of the tank.

[Andy CWS]

Because atmospheric tanks allow air to pass, there is always a chance that organisms (big and small) can enter into the water and breed.

A sanitation/disinfection system should be incorporated into your water treatment to prevent your water from becoming unpotable. Some are more effective than others and cost and maintenance will always be a factor in selecting the most suitable for your needs.

Andy Christensen, CWS-II