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Private Well Water Treatment

If bacteria, parasites, and chemicals are in your well water, you can improve the quality of the water with treatment. To make sure your water is safe for drinking, testing is your first step.

When test results show that your drinking water contains contaminants at levels above the safe limit, an appropriate water-treatment system or use of a clean alternative source (e.g. bottled water) is recommended. Long term, a more cost-effective solution for homes on private well water may be filtration systems such as a point of use reverse osmosis (RO) system or an ion exchange system.

Talk to water treatment companies and learn the pros and cons of treatment systems. Choose one that best meets your water quality needs by removing or reducing the bacteria and chemicals found in your water. If you decide to purchase filtration systems, it is recommended that you purchase a unit that is NSF International (formerly the National Sanitation Foundation) Certified.

Household Water Treatment

There are many different treatment options for the treatment of well water. No single treatment type will protect against all problems. Many well owners use a home water treatment unit to:

  • Remove specific contaminants
  • Take extra precautions because a household member has a compromised immune system
  • Improve the taste of drinking water

Household water treatment systems include two categories: point-of-use and point-of-entry.

To determine the best treatment option, contact a water treatment systems professional.

Point of Entry Systems

Point-of-entry systems are typically installed at the water well and treat most of the water entering a residence.

Point of Use Systems

Point-of-use systems are systems that treat water in batches and deliver water to a tap, such as a kitchen or bathroom sink or an auxiliary faucet mounted next to a tap.

Environmental Protection Agency (EPA) Filtration Facts

  1. Get the water tested by a third-party water testing laboratory (not the person selling you the equipment).
  2. Educate yourself on the different types of water treatment.
  3. Additional questions to ask:
    1. What maintenance is necessary? (replacement filter cost, can I do it myself, etc.)
    2. Can I throw away used filters in the trash or does it require special disposal?
    3. How much water does it waste?
    4. Will I need to supplement my diet? Can I use a water softener if I have high blood pressure?
    5. What types of things will void my warranty? What does the warranty cover?
  4. Shop around. GET IT ALL IN WRITING! (check with the Better Business Bureau (BBB))
  5. After installation, test again.
A water filter is a device which removes impurities from water by means of a physical barrier, chemical, and/or biological process. Examples of filtration systems include: activated carbon filters (such as Britta), and reverse osmosis (RO) systems.
Distillation is a process in which impure water is boiled and the steam is collected and condensed in a separate container, leaving many of the solid contaminants behind. Some water constituents removed through the distillation process may be beneficial to health.
Disinfection is a physical or chemical process in which pathogenic microorganisms are deactivated or killed. Examples of chemical disinfectants are chlorine, chlorine dioxide, and ozone. Note that chemical disinfection methods may result in formation of new undesired chemicals called disinfection byproducts which can be removed through activated carbon filters. Examples of physical disinfectants include ultraviolet light, electronic radiation, and heat.

Point of-use (at the kitchen sink) reverse osmosis (RO) treatment units are used by some well users to reduce concentration of metals in their drinking water.

RO systems are fairly small and are usually placed under the kitchen sink (point-of-use). Properly installed, RO systems will remove many contaminants from drinking water, including arsenic, uranium and radium. There are different types, brands and dealers of RO systems. It is recommended that you purchase a unit that is "NSF Certified" for the contaminants such as metals found in your drinking water. After installing the RO system, use the water from the RO faucet for drinking water, cooking, and making coffee, tea, baby formula and ice.

Boiling your water will increase, not decrease, metals concentration.
New Mexico has adopted the Environmental Protection Agency's (EPA) national drinking water standard for arsenic of 10 micrograms per liter (mcg/L). You can remove the arsenic to a safe level through reverse osmosis units for all water you drink and cook with, including beverages and food. Drink water from a clean alternative source (e.g. bottled water) until a filtration unit is added.

If you decide to purchase a reverse osmosis system you may want to consult with NSF International (formerly the National Sanitation Foundation) or at toll-free at 1800 NSF MARK (800 673 6275) to help make a decision of which model to buy. Treatments Options for Aresnic
If test results show that your drinking water contains more than 30 micrograms per liter (mcg/L) of uranium, an appropriate water-treatment system or use of clean alternative source (e.g. bottled water) of drinking water is recommended.

Point-of-use (at the kitchen sink) reverse-osmosis (RO) treatment units can reduce uranium concentration in drinking water. Properly operated household RO units can remove up to about 90 percent of the uranium from the raw water. It is recommended that you purchase a unit that is NSF International Certified and is effective in filtering radium (Ra-226 and Ra-228). After installing the RO system, use the water from the RO faucet for drinking water, cooking, and making coffee, tea, baby formula and ice. Other treatment methods, such as distillation and an ion exchange can also reduce uranium concentrations.

Learn more about NSF certified water treatment devices and search for a device that can meet your water quality needs.

Perfluorinated compounds (PFCs) are a group of man-made chemicals, including per- and polyfluoroalkyl substances (PFAS), with high thermal and chemical stability, long-distance transportation ability, and potential for accumulation in the food chain and human body. These chemicals have been widely used for decades in consumer and industrial products to make them non-stick and water resistant. They are found in firefighting foams, protective or stain resistant coatings for fabrics and carpets, paper coatings, insecticide formulations, paints and cosmetics. PFCs/PFAS are ubiquitous, can persist in the environment and move through soil and contaminate groundwater.

The EPA develops health advisories (HAs), which are not for regulation, to give information about compounds that can cause harmful human health effects and can occur in drinking water. An HA includes the level of the compound that is considered safe in water, taking into account exposure to food. To provide residents, including the most sensitive people, such as pregnant women, with a margin of protection from exposure to specific perfluorinated compounds (PFOA and PFOS) in drinking water, EPA established health advisory levels for both PFOA and PFOS at 70 parts per trillion (ppt) or nanograms per liter (ng/L). When PFAS are found in drinking water, the combined concentrations should be compared with the health advisory level. To say it another way, 70 drops of PFOA and PFOS in an Olympic-size swimming pool (660,000 gallons of water) is equal to the health advisory. This means even these small amounts of PFAS may be harmful. When levels of PFAS in water are higher than the EPA health advisory level, action should be taken to protect humans from eating or drinking the compounds. These actions could be taken by a water company changing how sources of water are blended or by the consumer using treated or bottled water. A health advisory value is not a clear line between levels that cause health effects and those that do not.

People served by a community water system (or municipal water supply) should contact their local water authority with questions about PFCs in their drinking water.

People who have private wells should get their water tested. Learn more about testing private well water. If tests show PFAS exceeding the health advisory, people should use other sources of drinking water. This is especially important for women who are pregnant, planning to become pregnant, or breastfeeding, as well as bottle-fed infants. Other sources of drinking water include water treated under the sink by a properly designed and maintained filtration system or bottled water. People who have private wells with any level of PFAS (from 1 ng/L to 69 ng/L) should consider, just to be as safe as possible, using other sources of drinking water.

Certain household filtration systems can remove these compounds from drinking water. If you decide to purchase a filtration system, hire a company that has experience in successfully removing toxic chemicals in private domestic well water. The system should be installed by a licensed plumber, and you should purchase a maintenance service contract for the system. Boiling does not remove perfluorinated compounds.

A list of water treatment options for removal of perfluorooctanoic acid (PFOA) and perflurooctane sulfonate (PFOS) can be found in the table below. Learn more about possible techniques and methods for the removal of PFAS in groundwater. One treatment that works for households is reverse osmosis, which can be installed under your sink. For information on water treatment companies or water treatment professionals in New Mexico, or if a water treatment professional has questions call 1-888-878-8992 or (505) 827-0006 or email

Maintaining a safe distance from sources of contamination (when feasible), routine maintenance, and routine water testing will help protect your private well water quality.
The healthiest thing you can do is lower exposure to these compounds. If exposure is from drinking water from a private well, there are treatment options designed to help reduce exposure by removing PFAS from the water.

There are some considerations when choosing a treatment system for PFCs/PFAS:

  • Boiling your water will not remove perfluorinated compounds from drinking water.
  • Reverse osmosis systems (if installed and maintained properly) can be more than 90 percent effective at removing a range of PFAS compounds (see table below for a list of water treatment options for removal of PFOA and PFOS). This treatment system does generate some waste water, therefore, a point-of-use system (under the sink) is recommended as the amount of waste water produced will be less than with a whole house system. Further, this type of water treatment system can generate a waste containing high concentrations of removed chemicals present in the water supply. Therefore, proper or safe disposal of such waste should be considered and planned for.
  • The treatment option should be certified (to meet the American National Standards Institute (ANSI) standards) to reduce the contaminant of concern below the EPA health advisory level. Find certified treatment options through NSF International (1 800 673 8010) or the Water Quality Association (630-505-0160).

    Treatment Type Notes Application PFOA Removal Rates PFOS Removal Rates
    Membrane Filtration (Reverse Osmosis (RO) and Nanofiltration) Multi-contaminant removal. Waste/by-products must be managed. Mineral addition may be necessary. Households (RO), Groundwater, Surface Water, Public Water Systems >90% >90%
    Granular Activated Carbon(GAC) GAC is the most common treatment method for PFAS removal. Presence of other organic compounds may reduce effectiveness. Households, Groundwater, Surface Water, Public Water Systems >90% >90%
    Powdered Activated Carbon(PAC) High concentrations of PAC are necessary. Required high concentrations may make this an infeasible option for water treatment. Waste residuals may create a challenge for disposal of waste products. Households, Groundwater, Surface Water, Public Water Systems >90% >90%
    Anion Exchange Single-use systems require replacement and proper disposal. Regenerable systems produce brine that must be disposed of responsibly; such systems are automated, have small footprints and high regeneration efficiencies. Competition with naturally occurring minerals can impact effectiveness. Groundwater, Surface Water 10-90% >90%
    Advanced Oxidation (UV/H2O2; UV/S2O8) Low removal rate. Can destroy pollutants to produce less complex compounds. Other organic contaminants will reduce efficiency. Groundwater, Surface Water <10% <10-50%

    Note: adapted from: National Ground Water Association (NGWA) document: Groundwater and PFAS: State of Knowledge and Practice (member available document). Table Source: Cheremisinoff , N. P. 2016. Overview of Water Treatment Technology Options in: Perfluorinated Chemicals (PFCs): Contaminants of Concern. Scrivener Publishing. Beverly, MA. ISBN 978-1-19-36353-8.

  • If you decide to purchase a filtration system, hire a company that has experience in successfully removing toxic chemicals in private domestic well water. The treatment system should be installed by a plumber licensed by the Construction Industries Division of the N.M. Department of Regulation and Licensing, and you should purchase a maintenance service contract for the system.

Learn more about perfluorinated compounds (PFCs/PFAS) and your health.
Floods, earthquakes and other disasters can damage or contaminate wells. If your well water has been contaminated or you suspect that it may be contaminated, do not drink the water. You need to properly disinfect or treat the water and have it tested before drinking/using the water. Drink clean water from another source until you are sure the water from your well is safe to drink again. What to do before a flood
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Content updated: Thu, 1 Nov 2018 07:44:19 MDT