To keep your well water clean and well operating at peak performance, regular water testing is a must. Private well owners are solely responsible for the quality of their drinking water. So, it is up to you, how and when to test your water.
- Initial Water Testing. Well water should be tested as soon as it is drilled. It should be tested if you are a new home owner and there are no records of the last time it was recorded. Or if you have recently purchased a home
- Annual Water Testing. It is wise to test the well’s water on an annual basis.
- Immediate Water Test. The well water should be immediately test if; a) there is a sudden change in taste, color, or odor. b) Someone in the home is pregnant or nursing. c) Failure in the septic system. d) After a flooding event. e) Someone in the home has a sudden, unexplained illness.
what contaminants should be tested
In Arizona, private well owners are responsible for the upkeep of their well and the quality of water it produces. While a loan provider or real estate company may require a water quality test, there are no federal or state laws that require a well owner to have their well tested. This means that Arizona well owners are solely responsible for testing their water, in order to protect the health of anyone who drinks it.
CONTAMINANTS IN your WELL WATER
Contaminants in well water may be present due to a variety of sources. Some may be present due to human sources, while others may occur naturally. Some contaminants, such as dissolved metals and nitrates, may be present due to both human and natural sources. It is important to remember that the presence of a contaminant in groundwater does not necessarily mean it will impact human health. The duration of exposure (i.e., how long you have been drinking and/ or cooking with the water), the concentration of the contaminant, your health, and many other “puzzle pieces” factor into whether a contaminant can make you ill.
Bacteria in Your Well Water
Coliform bacteria can be found naturally in the environment. They can also be present in the digestive systems of animals and humans. The bacteria themselves are unlikely to cause illness; instead, they are used to indicate the presence of other bacteria, viruses, or parasites that could make you ill. The specific presence of E. coli in well water is usually an indicator of fecal or sewage contamination, which can make you sick. It is important to discuss sampling and analyzing your well water for bacteria.
Nitrates in Your Well Water
Nitrates can occur naturally in groundwater and are usually found at levels that do not cause health problems. However, high levels of nitrates found in well water may be present due to contamination. This contamination may be from an over-application fertilizer, a leaking septic system (or one that is too close to the well), and animal waste. Nitrates can interfere with the body’s ability to properly distribute oxygen. This can be particularly concerning for infants or young children. “Blue Baby Syndrome” can occur when an infant ingests high concentration of nitrates, which can cause the skin to become discolored to a pale gray or blueish color). At high enough concentrations, nitrates can affect the nervous system or even cause death.
Arsenic in Your Well Water
Arsenic occurs naturally in the environment and can also be present in groundwater due to human activities. Arsenic is one of the most commonly occurring contaminants in Arizona’s groundwater and long-term exposure can cause skin problems and cancer. Many of the highest known concentrations of arsenic are located in the Southwestern portion of the Arizona.
Fluoride in Your Well Water
Fluoride is found in elevated concentrations across Arizona, particularly in some aquifers in the southern parts of the state. Though fluoride promotes healthy bones and teeth, too much fluoride in water can damage bones and cause tooth discoloration.
Radon in Your Well Water
Radon is an odorless, tasteless gas that cannot be seen or smelled. It forms when a radioactive metal, like radium, decays in rocks. The gas can dissolve into groundwater and could be present in drinking water from a private well. Radon gas can be released into the air when the water is used for domestic purposes. When inhaled, radon can increase the risk of lung cancer, and is the number one cause in non-smokers.
Salinity of Your Well Water
Many parts of Arizona’s groundwater sources have elevated levels of total dissolved solids that adversely affect household uses. Recommended water treatment options are also provided that may help manage well water quality.
INDICATIONS THAT A WELL NEEDS TREATMENT
Well owners may select water treatment options based on one, or more, of the four general symptoms shown in has a detailed contaminant-specific list of water quality issues with causes and suggested treatments. These symptoms affect water quality, are nuisances, and usually require some form of water treatment. But other more serious health-threatening contaminants may be present in well water such as arsenic, nitrate, and pesticides that cannot be seen, tasted or smelled.
TREATMENTS
To assist in the well water treatment selection, each with options depending on the quality of the water. The treatment sequence is important, and in most cases only one treatment step will be needed, but in others two or more steps may be needed and should be installed in order. For example, the water may first need to be filtered prior to chemical treatment. Aside from the symptoms described, it is important to test and measure the concentration of the contaminant to properly size the treatment option. After the installation of the system, a follow-up water test should be done to evaluate efficiency of contaminant removal. For example, arsenic treatment systems may remove only 80 percent of the contaminant, but the initial concentration may be such that you may need two systems in-line to assure safe water.
Particle and Microfiltration to Purify Well Water. Gravity-fed sand filters are capable of filtering soil particles and some types of pathogens when the filter is properly designed and maintained. ‘Natural’ filtration occurs as water infiltrates through the soils to the aquifer through a combination of physical, chemical, and biological processes within the environment. Well water filters may combine several layers of sand and coarser material to reproduce this natural process. Sand filters can be scaled to filter large volumes of well water but require periodic maintenance and monitoring to assure constant flows and water quality. Particle sand filters can also be effective in reducing the levels of bacteria and viruses in water.
Closed system (pressurized) sand filters are used in swimming pools to remove lime scale residues, but these are typically not used for drinking water treatment. Cartridge-based filters offer a practical solution of well water filtration since these can be installed in line without exposing the water to air and remain under pressure. Surface or screen filters, such as alumina and ceramic filters, can be used for particle and microfiltration depending on their pore size. Depth filters have a thick filter medium mostly made from synthetic polymeric materials fibers spun in different patterns to produce different size openings. These filters can also be used for particle and micro filtration. When possible, filters should be located indoors to avoid extreme temperature changes and cleaned or replaced regularly to prevent the formation of unwanted biofilms that can quickly clog fiber filters. Micro filters are usually rated using an absolute size cut-off, usually 1 micron or less. They are used to filter out pathogens like Giardia and Cryptosporidium, bacteria, some types of viruses, and fine soil and plant matter particles. These filters are not recommended for outdoor use and require frequent back flushing to control membrane fouling. They should be used after particle filtration to prevent early clogging.
Carbon Water Filters to Purify Well Water. This popular method of home water treatment is a form of ultrafiltration. Activated carbon filters lower the levels of dissolved organic contaminants from water but the mechanism of removal is a combination of physical and chemical processes. Activated charcoal filters contain cylinders of finely ground and compacted, chemically treated coconut shell (or other hardwood) charcoal. Carbon filters are commonly used to reduce the levels of residual chlorine taste if you are on municipal water, but are efficient in reducing odors, pesticides, solvents, and emerging contaminants from well water.
Some activated carbon filters may also reduce the levels of radon gas and some metals like lead from water. Carbon filters will not remove or lower the levels of salts like sodium or calcium, nitrates, or chlorides from water. Activate carbon filters will not soften or disinfect water. Particle-free water should be passed through carbon filters to avoid reduced efficiency and clogging. These point-of-use filters may be used in faucet attachments or in under the sink filter adaptors with a separate faucet. When treating potable well water, these filters may lower already very low levels, or dampen a temporary surge of some contaminants. If well water has elevated levels of a contaminant consistently above drinking water standards, these filters must be sized professionally and tested regularly. It is important to replace these filters at manufacturer recommended intervals.
Reverse Osmosis to Purify Well Water. Reverse Osmosis filters can also reduce the levels of many types of organic contaminants. The core of the system consists of a semi-porous membrane that filters out many types of soluble constituents, depending on its manufacture. The Reverse Osmosis process is a complex combination of sieving (filtering by size exclusion) and chemical reactions that occurs at the surface of the membrane. Membranes are rated according to their ability to exclude or retain certain types of ions; thus, the filtering efficiencies vary with constituent and membrane type.
Some pollutants may be prevented from passing 50 percent of the time while others more than 95 percent. Because the filtering efficiencies of these membranes can also be affected by the overall water quality, testing should be done after the reverse osmosis treatment to establish system efficiency. This is particularly important when using reverse osmosis systems to treat constituents that are consistently above drinking water standards in well water. Although reverse osmosis systems can filter particles, bacteria and viruses, they are not recommended for particle filtration or water disinfection. As with all filter media, microbial biofilms can develop, which can plug and shorten the life of these membranes, especially when not used regularly.
Nano filtration to Purify Well Water. This process is similar to reverse osmosis but uses membranes that block calcium and magnesium and many other water constituents but allow salts (sodium and potassium) to pass through. The “softening” membranes are more energy efficient since they work at lower pressures to produce equal volumes of water to reverse osmosis units. The filtering capabilities of nano filtration systems may be similar to that of reverse osmosis. Further development of this process may eventually lead to consumer nano filtration units that integrate the benefits of reverse osmosis with those of water softeners.
Distillation to Purify Well Water. Steam distillation effectively removes inorganic contaminants including suspended matter, salts, metals, and arsenic from water. It also removes most non-volatile organic contaminants. Volatile constituents, such solvents, may not be removed unless the unit has a venting system or an activated carbon post filter. Distilled water is corrosive and has a flat to sweet taste. Steam distillation also kills pathogens, effectively disinfecting the water. The steam distillation process is energy intensive and tabletop consumer units can use as much electricity as a toaster that is left on 24/7. The daily energy consumption may vary (usually increases) with water salinity and gallons of water produced. Consumers that plan extended or exclusive use of distilled water in their diets should consult with their physician.
Chemical Filters to Purify Well Water. Well water that is too acidic or contains abnormal levels of iron, manganese, and sulfides, can be treated with an alkaline filter to raise the water pH. After the pH is adjusted, the water is passed through a manganese (green sand medium) filter to precipitate iron and manganese and to convert sulfides to sulfate. Well water low in oxygen needs aeration to facilitate the oxidation and precipitation of iron and manganese. Aeration consists of bubbling air from the bottom of the water storage tank. Strong chemicals (oxidants such as hypochlorite) can be used to complete the oxidation process. This type of treatment is often used to remove dissolved hydrogen sulfide gas, the rotten-egg odor, from well water. Another source of hydrogen sulfide gas is a water heater with an electric anode made of magnesium.
The magnesium reacts with the sulfate in the water. If you detect the rotten egg odor from the hot- but not the cold-water faucets, the source is likely the water heater. To reduce gas production, a licensed plumber can replace the magnesium anode with a zinc anode, but the change may void the warranty. Well water that has high levels or iron, manganese, sulfides should be tested to determine the filter types and sizes required to treat the desired volume of household water. Balancing the required water pH changes and oxygen demand for the removal of iron and manganese from water can be difficult and usually requires professional assistance.
Iron Filter to Purify Well Water. Iron filters may offer a simpler alternative to the more complex RO systems when used to lower arsenic levels in well water. Since some iron minerals readily absorb arsenic from water, these filters are usually composed of tightly packed iron, or iron coated particles (beads), as shown in Figure 9.11. These filters are installed in-line and do not use electricity or extra water. Iron filters do not lower the levels of salts (TDS) or soften water. However, besides arsenic, they may also trap fluoride and selenium.
Chlorination of Well Water. Chlorine-based chemicals are commonly used to disinfect potable water by public water utilities. These chemicals destroy, or inactivate, most waterborne pathogens with some exceptions (some viruses and parasites). The most common chemicals are chlorine and chlorine dioxide gases, which are too dangerous for home use. However, liquids and solids that contain sodium or calcium hypochlorite can be used for household disinfection. UV light (see next section) can also be used to disinfect well water. Water chlorination systems can be continuous using chlorine pumps, suction devices, and solid feed units and batch disinfection. Continuous feed systems are automatic and flow-dependent with auto-shut off.
Chemical disinfection often produces toxic disinfection by-products when chlorine-based chemicals react with residual organic matter present in all water sources including groundwater. Continuous chlorination systems should be professionally sized and installed since they usually require a holding tank to allow for sufficient contact time to disinfect the water, and a booster pump. As with other forms of chemical treatment, water should be particle-free before disinfection, including chlorination. Since excessive levels of disinfection by-products in drinking water can be harmful to your health, chlorine disinfected water should be tested and, if needed, filtered through an activated carbon system to reduce the levels of these chemicals.
UV Radiation to Purify Well Water. Ultraviolet (UV) light may be used to disinfect particle-free, clear water on a continuous flow mode using follow-through glass tubes with an enclosed UV light source. UV is damaging to living organisms and viruses that contain RNA and DNA material, stopping their ability to reproduce or infect other cells. Therefore, waterborne organisms like bacteria, viruses, and even some parasites may be quickly inactivated (killed) when exposed to a concentrated source of UV light. UV light disinfection systems are simple and relatively maintenance-free but their efficiencies depend on the design and UV light source type and power, the water flow rate, and the amounts and types of pathogens and other microorganisms present in the water source.
UV light disinfection systems are rated by the NSF as Class A for more aggressive treatment of clear, but contaminated water (not wastewater). UV light Class B systems may be used to further lower contaminants in safe drinking water. Both systems require particle-free water. UV light disinfection does not change the taste of water or produce any known disinfection by-products. Unlike chlorination, it does not provide any residual disinfection protection to the disinfected water. If the well water is contaminated, pre and post water testing for waterborne pathogens should be done determine the disinfecting power of the UV light system.
Emergency Methods to Purify Well Water. In emergency situations water may be boiled vigorously for at least two minutes to kill all organisms. Household chemicals, such as bleach or iodine, may be used to disinfect water under emergency. For more details and guidelines for the use of bleach, and other chemicals, to disinfect water under emergency situations, visit EPA website: https://www.epa.gov/ground-water-and-drinking-water/emergency-disinfection-drinking-water.
ACCREDITED well water TESTING COMPANIES
Several companies in Arizona have been accredited and certified to test well water. You can search for these certified well water testing laboratories by clicking HERE.
SCHEDULE PHYSICAL INSPECTIONS OF THE WELL
Regularly inspect your wellhead for damage to the casing or well cap. Repair any damage immediately to reduce the potential for contamination. Store all chemicals at least 100 feet from your well. Keep heavy equipment and vehicles off your lawn and away from your well to avoid damage to buried water lines. Other than grass, do not let plants grow near your well as plant roots can cause damage to your well casing.
If you need help from an experienced Arizona water law attorney, then contact the Dunaway Law Group at 480-702-1608 or message us HERE.
The information provided is informational only, does not constitute legal advice, and will not create an attorney-client or attorney-prospective client relationship. Additionally, the Dunaway Law Group, PLC limits its practice to the states of Arizona and New York.