New well & water softener advice

[MexicaliBill]

Hi-

We recently bought a lake cabin in Minnesota, and put in a new well in November, about 75 ft deep. The previous owners had used a shallow point well and used a 5 gallon dispenser for drinking water. We know we need some kind of water softener on our new well, but there are a bunch of other issues to take into consideration, and we're getting a little overwhelmed trying to sort through all the variables. In the meantime, we're still using the 5 gallon jugs for consumption.

1. Our water softener will have to go in the basement, under the stairs, where space is at a premium, so a smaller system is better.

2. There is no floor drain, so any regen/flush will need to travel up 5 feet, then horizontally 20 feet, before draining being tied into the stack. The plumber roughed in a 3/4" pex pipe (not connected on either end). We also have electric line roughed in for any electric needs.

3. Our cabin has a holding tank. Therefore, we want to minimize the use of waste water for any treatment. We normally also turn off the water and well pump when we're not here. Leaving the system on when we're not there to regen and overflow the holding tank would be very unpleasant.

4. Most of the time, it's just 2 of us. We've used the place enough to know that we use about 75 gallons per day total. That calculation is based on the 1500 gallon holding tank, and how often we need it pumped (every 3 - 4 weeks). There will occasionally be more people here for short periods (e.g., 8 people for a holiday weekend).

5. I've had the water tested by a local lab. Once in December for a bunch of stuff, and then again this month for bacteria and arsenic. Results:

Coliform: negative (December & April)
E. coli: negative (December)
Nitrate: < 0.5 ppm
Arsenic: 8.91 ug/l (December), 17 ug/l (April)
Sodium: 3.73 ppm
Calcium: 51 ppm
Magnesium: 12.4 ppm
pH: 7.73
Sulfate: 17 ppm
Conductivity: 0.368 mmhos/cm
TDS: 239 ppm
Hardness: 10.4 gpg
Iron: 0.44 ppm
Manganese: 0.181 ppm
Chloride: 5 ppm
Fluoride: Not Detected

6. After not using the new well at all for almost 3 months (January - March), when we turned it on this month, we noticed a sulfur smell in the water (hot and cold). Is this possibly a seasonal issue, or do I need to shock the well as part of spring maintenance, or do we need a system that can filter sulfur permanently? If the shocking fixes it, how long do I have to wait to see if it comes back before knowing whether it was a temporary problem or permanent? Do I need to take a sample to determine the level, and/or can we add something to our system later if it becomes a chronic issue?

I'd like to handle the arsenic just for the refrigerator line (I will use it for cooking too). I have a few opinions on what to do but I'd like to hear from those with far more than my zero experience with the type and brand and model of system to install. I tried calling one of the franchise dealers, who came by to sell me a $7,000 unit on the spot. The other franchise wanted me to rent a unit, because he said water changes all the time so I shouldn't buy one. I passed on both.

I really appreciate any advice on the best way to proceed.

Thanks,
Bill

 

[Reach4]

1. Our water softener will have to go in the basement, under the stairs, where space is at a premium, so a smaller system is better.

Space like floor space or height?

2. There is no floor drain, so any regen/flush will need to travel up 5 feet, then horizontally 20 feet, before draining being tied into the stack. The plumber roughed in a 3/4" pex pipe (not connected on either end). We also have electric line roughed in for any electric needs.

Up 5 and over 20. What keeps things from freezing? I think having the line drain in the freezing part after a backwash is good. That could call for a vacuum breaker indoors on the drain line, and the line sloping downhill after that.

3. Our cabin has a holding tank. Therefore, we want to minimize the use of waste water for any treatment. We normally also turn off the water and well pump when we're not here. Leaving the system on when we're not there to regen and overflow the holding tank would be very unpleasant.

I don't think that is a factor, unless you get an RO. Then you will need to figure out where that drains. It will drain slowly over a long period, rather than squirting out water all at once occationally.

One thing to consider is whether your pump can deliver 2.4 gpm for backwash of a softener. Your softener might need less, but if you can do 2.4 gpm from the pump during several minutes of backwash, you should be fine.

4. Most of the time, it's just 2 of us. We've used the place enough to know that we use about 75 gallons per day total. That calculation is based on the 1500 gallon holding tank, and how often we need it pumped (every 3 - 4 weeks). There will occasionally be more people here for short periods (e.g., 8 people for a holiday weekend).

You might trigger an early regen when you expect company.

5. I've had the water tested by a local lab. Once in December for a bunch of stuff, and then again this month for bacteria and arsenic. Results:

Arsenic will be ok for washing but you would avoid drinking. A softener will not remove arsenic. Iron and manganese will put a load on the softener. You will compensate. An RO unit will remove arsenic for the fridge and drinking.

6. After not using the new well at all for almost 3 months (January - March), when we turned it on this month, we noticed a sulfur smell in the water (hot and cold). Is this possibly a seasonal issue, or do I need to shock the well as part of spring maintenance, or do we need a system that can filter sulfur permanently? If the shocking fixes it, how long do I have to wait to see if it comes back before knowing whether it was a temporary problem or permanent? Do I need to take a sample to determine the level, and/or can we add something to our system later if it becomes a chronic issue?

https://terrylove.com/forums/index....izing-extra-attention-to-4-inch-casing.65845/ is my sanitizing writeup, but it is not written with a sandpoint in mind. I am not sure how you would recirculate. I could imagine a method. You probably have a plug you could remove to pour water in as a flooding volume.

So anyway, I expect a more thorough sanitizing with reduced pH and flooding volume will make the good effects last longer. But I cannot predict how long. I would be thinking every spring as a guess.

 

[Sponsor]

 

[Bannerman]

I suspect the holding tank is for grey water and sewage discharge.

I think the drain line distance is within the basement or crawl space, leading from the intended softener location to the drain stack which exits to the waste holding tank.

I anticipate the electrical installation mentioned is an outlet for the softener.

An under-sink RO filteration system would be the best choice for purified water, assuming there is sufficient water pressure. The amount of RO waste water will be drastically reduced when a permeate pump is also utilized.

 

[MexicaliBill]

Thanks for all the responses. A couple of points to clarify:

1. I'm tight on space to place the unit in every direction (width, height, and depth), but height is the most limiting under the stairs. I'll figure out how to make it work, but, all things being equal, smaller physical unit is better.

2. I do not have a sandpoint. That was the old well. We put in a new, drilled well in November, so I can shock it using a normal process.

3. The holding tank gets all wastewater, including whatever comes from the future softener, RO sytem, etc. I thought RO's used about 3 gallons of waste for every 1 gallon made. Those 3 gallons would go right into the holding tank, which is not ideal. I was hoping for a non-RO method for the arsenic, if possible, but if RO is the best option for POU, that's what we'll do.

4. Although we are not here in the winter, we do leave the heat on, so we aren't blowing out pipes, etc., and it shouldn't freezer. It's a walk-out basement, if that matters.

5. I'm not sure what pump you are talking about. Is that for the RO system? I was hoping regular line pressure would be enough for regen on the softener. If I need a lift station pump, we can add one, but was hoping to avoid that.

 

[Reach4]

1. I'm tight on space to place the unit in every direction (width, height, and depth), but height is the most limiting under the stairs. I'll figure out how to make it work, but, all things being equal, smaller physical unit is better.

Give a dimension for your height limit.

2. I do not have a sandpoint. That was the old well. We put in a new, drilled well in November, so I can shock it using a normal process.

Nice.

3. The holding tank gets all wastewater, including whatever comes from the future softener, RO sytem, etc. I thought RO's used about 3 gallons of waste for every 1 gallon made. Those 3 gallons would go right into the holding tank, which is not ideal.

With a booster pump, you could get closer to 1:1 I think. But if it is not freezing outside, that drain water can just go outside. The plants will like it fine.

There are also "zero waste" RO systems. Those put the drain water into the hot water, for washing etc.

5. I'm not sure what pump you are talking about. Is that for the RO system? I was hoping regular line pressure would be enough for regen on the softener. If I need a lift station pump, we can add one, but was hoping to avoid that.

There are two types of pump for RO. A permeate pump, and electric pump.

 

[Bannerman]

There are now newer RO membranes that do not need as much drain flow to flush contaminants from the RO membrane. Membranes such as Pentair GRO have the ability to reduce wastewater requirements as low as 1:1.

The storage tank maximum pressure for most RO systems is limited to approx 60% of the feed water pressure. The wastewater vs RO water produced will be lowest when there is minimal back pressure on the membrane which is when RO water in storage is least and the pressure is lowest. As more RO water is added to the tank, the tank pressure will rise which will reduce the membrane's output. This is true for either conventional or GRO membranes.

A Permeate pump is a non-electric pump that is driven by the energy in the wastewater. It is placed between the RO membrane and the storage tank to pump water exiting the membrane into the storage tank, thereby reducing back pressure on the membrane. This will allow an increase in water production efficiency which will reduce the quantity of wastewater while also increasing the quality of RO water produced. Further benefits are, the storage tank will fill more quickly and the pressure may be increased to 90%+ of the feedwater pressure, which could be of benefit when using a fridge ice & water dispenser.

Although a GRO membrane may be used with a permeate pump, the wastewater flow will usually need to be increased since the lowest flow rate is usually too low to operate the pump properly. A conventional membrane will require greater waste flow, but the use of a permeate pump will reduce the run time needed each day, thereby further reducing the amount of wastewater for every day of use.

Here is an animation which shows how a permeate pump operates: https://www.permeate-pump.com/ERP1000ben.htm

 

[MexicaliBill]

I have about 65" of height under the stairs if I put it where I don't want it, and 40" if I put it in my preferred location. Depth and width about 30".

I cannot drain RO water to anything but the holding tank. We're way too close to the lake, even if I could find a way to pump the water out somewhere, which would be pretty challenging.

Are all these RO systems you are talking about whole house? Is it to deal with the sulfur and/or arsenic, vs. a regular softener? Can I use a result softener with an iron filter (like a Katalox) for POE and an in-line arsenic filter for the POU fridge?

 

[Bannerman]

The RO system recommended would be an under-sink unit plumbed to a separate faucet normally located in the kitchen as well as the feed to the fridge. The drain flow is not toxic but does contain the dissolved solids that were removed from the water, which are likely much of the same dissolved solids that are found in the lake.

My municipal well water also contains arsenic so all water utilized for drinking and cooking and also for filling our clothes iron and ultrasonic humidifier is obtained from our RO unit. Because I located our RO unit in the basement laundry room directly below our kitchen, I installed an additional faucet beside the laundry room sink.

 

[Reach4]

I have about 65" of height under the stairs if I put it where I don't want it, and 40" if I put it in my preferred location. Depth and width about 30".

The brine tank can be many feet away if that helps.

A 12 x 29 tank could hold about 1.1 cubic ft of resin. A 5600sxt valve would add about 9 inches of height. I think that would do it for you. I am not sure how you slide that if you want to move it. https://view.publitas.com/impact-water-products/2018-catalog-final/page/138

A 15x17x36 high brine tank would be a possibility, but there are shorter ones, such as 11x11x36. You want to be able to lift the lid to pour salt. Maybe put that on some short rollers? https://view.publitas.com/impact-water-products/2018-catalog-final/page/132

Are all these RO systems you are talking about whole house? Is it to deal with the sulfur and/or arsenic, vs. a regular softener? Can I use a result softener with an iron filter (like a Katalox) for POE and an in-line arsenic filter for the POU fridge?

No, No, huh?
We were talking about an RO under the sink.

 

[ditttohead]

A few minor comments.

As bannerman mentioned, permeate pumps are great but they tend to have problems with ultra efficient settings. We simply have not had great luck with them when we are trying to do 1:1 designs. Many companies still order them from us that way but we prefer to go 2:1, that tends to be the sweet spot for it working very well.

GRO and other ultra high efficiency membranes have worked far better than we ever thought they would. The market for these have grown massively as our customers truly love the lower waste these units offer without too much sacrifice in performance. We have tested the GRO membrane at far more efficient settings. Our in house testing protocol calls for a .25:1 waste ratio for 3 months on city water that has been dechlorinated, 5 micron pre-filter, 15 GPG hardness, approximately 200-250 TDS incoming, with dozens of employees using the water. We continuously monitor water quality and production rate and so far a couple of the membrane manufacturers have passed our testing.

Your arsenic exceeds the EPA MCL of 10 ppb. Arsenic has some skin absorption potential but your levels are very low. For obvious reasons I must recommend removing it from the whole house... but if it were my house, I probably would not spend the money/maintenance to remove this low of a level.

Modern high end softeners can be programmed to use very little water. This is easily achieved but some minor tweaking may need to be done to ensure the system works properly, not difficult. Our standard settings basically work great in 99% of applications, and they use a little more water than they need to. Since water is a renewable resource and plentiful in many areas, this is not a problem. In your situation, setting the softener for extreme water efficiency probably is worth the trade off.

Do you have 40" of height or possibly 42"? Double check, this is a huge difference as we can do a lot with a couple extra inches. 18x26 brine tanks are very popular for height restricted locations.

If the unit is going to be installed in a location that can suffer water damage, be sure to install a leak detector and shut off device.

 

[MexicaliBill]

The stairs come down at an angle, so the height also depends on the width. But, I can put it to the left of the water heater if necessary, under the pressure tank. That's 46.5" of height.

 

[ditttohead]

12x35 is an awesome tank size, slightly under minimum recommended bed depths but the physics still play out quite acceptably. I sent you a PM.