Can copper sulphate be removed from water supply?
I have copper sulfate in my water supply confirmed by the supplier which they say is coming from my copper piping. I have a filter on my kitchen faucet so I can use the water for drinking etc. I am planning on replacing all the piping that I can reach with PVC. The house is a 50 year old rancher so I can reach everything but the short vertical runs to the kitchen and baths. The water heater is 20 plus years old so I will replace that as well. Before I do all that work I was wondering if there is an easier solution? Is there a product that I could use to flush out the piping – like bleach like you use when treating a new well? If so, how would it be done? Will replacing most of the pipe while leaving the short vertical copper pieces eliminate the problem (I suspect most of the problem would be in the horizontal runs)? I will also have to deal with the house electrical grounding system – everything uses the cold water supply line for grounding. Any opinion would be appreciated.
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There is a long joke regarding a dog that won't stop digging in the garden. The owners bring the dog to the vet, and the vet does what he can. It slows the dog down, but he keeps digging in the garden. The owners bring the dog back to the vet, and ask if there is anything else he could try. The vet looks the dog over and says "Well, I guess we could try amputating his hind legs too".
I am not an expert, but I would suggest that you research the problem more before you start replacing your copper pipes. It would probably work, but seems like a rather drastic solution. Copper has been used safely for water supplies for a very long time. Copper sulfate doesn't just "leach out" from pipes over time. If it's there (and not in the incoming water supply) it's being produced because something else is wrong with your system.
Replacing the sacrificial anode on the water heater and checking that the grounding is done correctly seem like good places to start. Some other possibilities are discussed in these links:
http://www.plbg.com/forum/read.php?1,248244
http://www.finishing.com/304/79.shtml
Phillip,
If you do replace your copper tubing with a different material, I recommend that you choose Pex. You suggested using PVC, but I don't think that PVC is legal for water supply pipes. (Perhaps you meant CPVC.)
Pex is preferable to CPVC, in my opinion.
Phillip,
From what you wrote, it's not clear to me that you have a problem. You didn't write excatly how much copper is in your water that was sampled. EPA has determined that copper levels up to 1.3 ppm (or mg/liter) is considered safe. Also, water samples need to be collected carefully and the water should run for 30 seconds before a sample is collected. Don't let the water sample container come in contact with the faucet. Take the sample from a frequently used faucet such as the kitchen or bathroom. A single sample may not be a good indicator of the quality of your water.
In addition, if your copper pipes have been corroding badly for the past 50 years you would have had serious problems with staining of fixtures and leaking copper water lines. And you would be worried about the amount of dissolved copper in your water, not specifically copper sulfate. There can be lots of sulfate in your water without causing any problems.
This link has good info on copper in drinking water:
http://water.epa.gov/drink/contaminants/basicinformation/copper.cfm