arsenic removal private well

[andysail]

Open to input for arsenic removal on private well. Have a water softener and everything else tested ok. Originally lab tested result was 20 ug/l for the arsenic. A under sink arsenic filter was put in place with a media filter specific for arsenic removal. Unfortunately after testing water a month after use, it was only reduced to 16 ug/l. The under sink unit is rated for 15K gal, and a unit about 4" diameter x 20" tall. I haven't been drinking the water or cooking with it. Was hoping to get it level well below the epa level of 10 ug/l. I've been looking at other whole house backwash systems but best to get the tried and true advice up front if possible. I checked out a few other posts on here also.. thanks in advance...

 

[andysail]

This is the pitch for the under sink filter:
Our filters utilize MetSorb material to efficiently eliminate heavy metals like arsenic III & V, lead, mercury, cadmium, and other contaminants. Plus, their exceptional adsorbent capacity extends replacement

 

[Sponsor]

 

[Bannerman]

An under sink media filter will have only limited effectiveness due to the long contact time required with the limited quantity of media.

How much iron is in your well water?

Because Arsenic has a tendency to bind to and precipitate out with iron oxide, water treatment which oxidizes and filters out the oxidized iron, will typically also reduce arsenic to safe levels. This type of treatment should be located prior to a softener.

Consider an under sink Reverse Osmosis system to supply water for drinking & cooking. While RO has an ability to effectively eliminate Arsenic V and a wide range of other contaminants, it will typically remove only 40-75% of Arsenic III. For an RO unit to remove Arsenic III, will first require the Arsenic III to be oxidized to cause it to be converted to AS V.

There are other methods to remove arsenic including arsenic specific Anion ion exchange media placed into a backwashing filter tank, similar in style and size as a water softener.

 

[DrBoom]

We have a whole house metsorb tank that has been very effective with no detectable arsenic passing the tank. In our case, there are a pair of metsorb tanks and we test between them. When there is detectable arsenic, they replace the media in the "used up" tank and swap the positions. That took about a decade the first time we needed to replace the media.
In our case, we also have a sediment filter first, the arsenic tanks and then a granulated activated carbon tank before hitting the UV filter to squash any bacteria that makes it through.
This was not inexpensive. I don't know what it cost to install the system since that was done before we bought the house but, replacing the metsorb media in 1 tank and the GAC media was nearly $2k in parts and labor. I imagine that the cost for doing a point of use system would be much less.

 

[andysail]

An under sink media filter will have only limited effectiveness due to the long contact time required with the limited quantity of media.

How much iron is in your well water?

Because Arsenic has a tendency to bind to and precipitate out with iron oxide, water treatment which oxidizes and filters out the oxidized iron, will typically also reduce arsenic to safe levels. This type of treatment should be located prior to a softener.

Consider an under sink Reverse Osmosis system to supply water for drinking & cooking. While RO has an ability to effectively eliminate Arsenic V and a wide range of other contaminants, it will typically remove only 40-75% of Arsenic III. For an RO unit to remove Arsenic III, will first require the Arsenic III to be oxidized to cause it to be converted to AS V.

There are other methods to remove arsenic including arsenic specific Anion ion exchange media placed into a backwashing filter tank, similar in style and size as a water softener.

My iron level was low enough I was told the softener would handle the minimal amount. I had a AG lab do the tests originally so I could see them but didn't do any heavy metals til recently. I also wasn't drinking the water prior because the maganese was very high and fortunately the water softener reduced it drastically to almost no detection. Everything else is great except the the arsenic. I did read different type of arsenic removal methods can also be specific to type lll VS type V. The under sink was a inexpensive shot, more so for the fridge water supply. Thank you for the info.

 

[andysail]

We have a whole house metsorb tank that has been very effective with no detectable arsenic passing the tank. In our case, there are a pair of metsorb tanks and we test between them. When there is detectable arsenic, they replace the media in the "used up" tank and swap the positions. That took about a decade the first time we needed to replace the media.
In our case, we also have a sediment filter first, the arsenic tanks and then a granulated activated carbon tank before hitting the UV filter to squash any bacteria that makes it through.
This was not inexpensive. I don't know what it cost to install the system since that was done before we bought the house but, replacing the metsorb media in 1 tank and the GAC media was nearly $2k in parts and labor. I imagine that the cost for doing a point of use system would be mu

 

[andysail]

Unfortunately the arsenic level I have will require a whole house system and because of cost I am trying to do it properly the first time. The under sink unit I tried with metsorb was around seventy five bucks, and will help with fridge etc.. thank you for reply

 

[andysail]

With my 1 bedroom 1 person residence,
after lots of research and reading last few weeks I've found that there are many variables dependent on the water lab test results and the treatment in most part can/will vary differently for each individual. If you are going to do this treatment for arsenic types be prepared to read a lot and understand the multiple steps that may need to be done first, it's all dependent on what you've already done and your various water test results..
I ended up ordering a 10x54 tank with a fleck 5600Stx filter controller.
I researched various sites and opinions on utilizing a gravel bed or not with the decision to. I ended up purchasing organic poultry grit #2 quartzite for my gravel bed and plan to prewash it outside and soak in bleach water a bit and rinse. Should use a respirator mask for any stray silica dust etc.. approximately 15lb needed for my size tank and person ($8.99 50lb) at a farm n barn store...don't use the aquarium stuff as it's potentially coated with resin of sorts etc non organic...
Decided to go with Metsorb HMRG resin as its a adsorb, for arsenic type III and V, with one better than the other along with other various metals and some pfos. (Not cheap). Calculated 1.5 cu ft. For my size tank, 1.5 min to 3 min stand time.. treatment specs references for Arsenic 60 ug/l and below.
To soon to tell what the results will be as I expect to have everything together in a week when I can take the time to put things together and put in place..gives me time for the constructive criticism to come in...

 

[andysail]

We have a whole house metsorb tank that has been very effective with no detectable arsenic passing the tank. In our case, there are a pair of metsorb tanks and we test between them. When there is detectable arsenic, they replace the media in the "used up" tank and swap the positions. That took about a decade the first time we needed to replace the media.
In our case, we also have a sediment filter first, the arsenic tanks and then a granulated activated carbon tank before hitting the UV filter to squash any bacteria that makes it through.
This was not inexpensive. I don't know what it cost to install the system since that was done before we bought the house but, replacing the metsorb media in 1 tank and the GAC media was nearly $2k in parts and labor. I imagine that the cost for doing a point of use system would be much less.

Hello, I appreciate the info and did a lot of reading and discovering information to all the individual aspects that play a part in arsenic. With what I had in place already and low iron I ended up putting together another larger metsorb HMRG backwash filter tank unit for about $1600.. wondering if you have dialed in the backwash cycle or how many days, 14 seems to be the norm. Or maybe your system doesn't utilize backwash and is simply a downflow filter system without a controller. If you ever want to attempt the media replacement I found a place in Arizona that manufacturers filters and sells the Metsorb that was considerable less compared elsewhere.. I'm waiting for five dollars in parts as my new controller was missing them but anxious to see how well my unit responds or works. Do you know what your arsenic levels are pre filter, the metsorb hmrg is rated for 60 ug/l or lower.. thanks