Introduction-
All of the above contaminants create health related problems
(EPA
primary contaminants) and therefore should be tested
by a certified lab. We recommend treatment of all of these contaminants by P.O.U. (point of use) R.O. (reverse osmosis) systems. All of these contaminants, with the exception of Nitrates/Nitrites,
create health problems when ingested over long periods of time. Please see EPA primary contaminate list
for the health effects of these parameters.
Arsenic-
Arsenic that is found in ground water can be due to the use
of pesticides, rodent poisons, landfills or introduced naturally by the erosion of bedrock. Naturally occurring
arsenic exists above the present MCL (maximum contamination level) in 10% of the ground water wells in Maine. This
means that on average every 10th well will have arsenic above desirable levels. To
find out more about arsenic's health effects try reading these NIEHS news letter , Information on Asenic in Well Water ,
Arsenic Treatment
for Homeowners , or article from the Portland Press
Herald"State urges
wells be tested for arsenic"
Lead-
Lead is rarely found in ground water. It is almost always
introduced by the corrosion of lead in the water delivery system. This lead can be found in old solder, brass fixtures
and sometimes lead pipe or connections. It is sometimes controlled by removing the source (installing new pipes
or fixtures).
Nitrates/Nitrites-
Nitrates/Nitrites are usually elevated in areas of heavy
farming. The heavy use of fertilizers or animal waste can be the cause of this problem. These contaminants can
be removed by the use of anion resins but we do not recommend this method because there is no easy way for the
homeowner to continually monitor the performance of the system. If not properly designed or operated, an anion
system can actually bleed nitrates back into the water. This bleeding can cause concentrations of nitrates in the
treated water to be higher than that found in the raw water.
Radioactive Nuclides-
The initial screening for radioactive nuclides is called
a gross alpha test. The name comes from the fact that the test is determining the total (gross) amount of alpha
radioactivity. Radon is not detected in this test because it is a gas and the test only checks for the activity
of dissolved radioactive solids. In most cases, this activity is due to uranium or radium. If the gross alpha is
above recommended levels, testing for uranium and radium will be recommended by the lab. In the case of residential
treatment, the distinction between uranium or radium is not necessary because the treatment will be exactly the
same -R.O.
Treatment-
In a residential setting, all of the above contaminants should
be treated by a P.O.U. (point of use) R.O (reverse osmosis) system. The R.O. is chosen for two reasons -
- These parameters are only a problem if ingested and therefore
only enough water for drinking is necessary.
- R.O. systems provide for system performance checks on a
regular basis by the homeowner. We use smart faucets that have lights that tell the customer every time he draws
water if the system is operating properly. There is no other treatment technique that will allow this type of monitoring.
As with any time an R.O. is recommended, special attention should be given to the quality of the water that the
R.O. will be treating. All R.O. systems we install to treat these parameters will have some type of "smart
faucet" that will monitor the performance of the system. When an R.O. is installed percent reductions are
all that can be promised. For example, if the raw water concentration increases the product water concentration
will also increase. Provide for at least a 20% margin of safety for changes in raw water concentrations. The following
percent reduction can be obtained with Water
Factory SQC series provided a system pressure of
40-60psi can be maintained, the TDS is (<500ppm) and the storage tank is drained regularly. See the table of actual results from some of our installed systems.
|
Contaminant
|
Percent Reduction
|
| Arsenic |
>90%
|
| Gross Alpha |
>98%
|
| Nitrates |
>75%
|
|
