Residential Testing - Interpreting Results

COLIFORMS/ECOLI

Any coliforms presence in drinking water is cause for action. Groundwater in a properly constructed well or spring should be free of coliforms bacteria. If coliforms are found in a well or spring, it generally means that surface water has somehow leaked into the water. This could happen if rain runoff or snow melt makes its way into the well or spring through cracks in ledge outcroppings, gravelly soil, or sandy soil. It could also be due to poor construction or cracks in the well or spring casing. Coliforms bacteria may enter the water supply if rain or snow runoff pools around the well or spring casing, if the well or spring cover is not airtight, or if the pipe leading to the house is not properly inserted and welded or grouted into the well or spring. In addition, insects, snakes, mice or other creatures getting into the well or spring can cause contamination.  If coliforms are present, Pace will continue the test and check for Ecoli.
The drinking water guidelines state drinking water should not contain more than 10 total coliforms bacteria per 100 mL of water.
Your test will results will either be A=Coliforms bacteria is absent or P=Coliforms bacteria is Present.

NITRATE

Nitrate in elevated levels is linked with two known health problems. Methemoglobinemia or “blue baby syndrome” is caused by an oxygen deficiency in the blood. This causes bluish skin tone in infants. In adults, nitrates can form chemicals called nitrosamines that have been linked to cancer. These may pose long-term health risks. Elevated nitrate levels in well water may also indicate other problems such as contamination from sources such as septic systems or fertilizers.
The maximum level for nitrate in water is 10.0 mg/L. However, when levels exceed 5 mg/L, the source of nitrate should be investigated.

PH

PH is a measure of acidity. Acidic water, along with low hardness (soft water), tends to be corrosive to your water pipes, potentially dissolving lead and copper. Basic water itself is not a problem, but may have a bitter taste. Alkalinity, which is a separate measurement, is your water’s capacity against drastic pH changes.
The scale is 0 – 14
0 to 5 is acidic (not desirable)
5.5 to 8.0 is average.
8.5 to 14 is basic (or alkaline)

SODIUM

Sodium is a necessary dietary element and occurs naturally in all water, but more so in areas where there is sea water, salt from septic systems and road de-icing salt may elevate levels in wells and indicate other water problems. Sodium has no set health hazard level, but those individuals on a low sodium diet should take into account the amount of sodium in their drinking water when determining overall sodium intake. High levels of sodium in drinking water may cause an unpleasant taste. For people with sodium restricted diets it may cause health problems by contributing to high blood pressure.
32 mg/L is considered average. Levels above 50 mg/L may affect performance. 250 mg/L is the maximum level for sodium in all drinking water.

IRON

Iron becomes a nuisance element. It will show its presence as rust stains on water fixtures and if chlorine bleach is used in the laundry, rust spots will appear on clothes. If this happens, use non-chlorine bleach with your clothes. Common iron removal methods include ion exchange and oxidation filtration.
Average Iron level is 0.2 mg/L. The maximum acceptable level is 0.3 mg/L. Higher levels produce a bad odor and taste.

MANGANESE

Manganese does not cause health problems at levels typically found in drinking water and it is an essential element for human metabolism. However, manganese can discolor water; stain clothing, sinks, toilets and bathtubs; and can cause undesirable tastes in drinking water.
The maximum level for manganese in water is 0.05

CHLORIDE

Chlorides do not cause health problems, but high chloride levels in drinking water may be a sign of other problems. Consuming too much chloride (Cl) has a detrimental effect on metabolism. The EPA standard has been set at the level at which the average person notices an unpleasant salty taste. Chloride contamination is associated with infiltration of road salt leaching into water supplies or backwash from a water softener and/or sea water.
14 mg/L is considered normal for well water. The maximum level for chlorides in well water is 250 mg/L

LEAD

Lead is a highly toxic metal that can cause serious health problems, especially for infants, children, and pregnant women. Nervous system, kidney, and red blood cell problems may be effects of exposure to high lead levels. In young children, lead may have harmful effects on nervous system and brain development. Lead has been used in making solder, fittings and fixtures found in household plumbing.
The maximum level for lead in water is 0.015 mg/L

HARDNESS

The contributors to hardness are calcium and magnesium. The presence of these elements in general is not a health hazard, but hardness elements tend to plate out on water pipes and heating coils in hot water tanks, and reduce the effectiveness of detergents. Hard water causes stains, leaves residues, or causes other physical problems in water-handling equipment.
Low (Soft) 0 – 75 mg/L
Moderate 76 – 150
Hard 151 – 250
Very Hard 251 +
Concentrations on the order of 1 part per million are considered optimum.

FLOURIDE

Fluorides in water can be detrimental or beneficial depending upon the concentration. If the water contains over 1.5 parts per million of fluorides, use of this water during the period of tooth formation causes a condition known as “endemic dental fluorosis”, a dark brown stain on the teeth. It is therefore necessary to remove fluorides present in such high concentrations. Recent work has shown that low concentrations of fluoride taken during tooth formation can minimize tooth decay.
Concentrations on the order of 1 part per million are considered optimum.

ARSENIC

Arsenic occurs naturally in rocks, soil, air, water, plants and animals. It can enter well water through the ground or as a run off to surface water sources. Arsenic can be further released into well water through natural activities such as erosion of rocks and forest fires, or through human actions. Approximately 90 percent of industrial arsenic in the U.S. is currently used as a wood preservative, but arsenic is also used in paints, dyes, metals, drugs, soaps and semi-conductors. High arsenic levels can also come from certain fertilizers and animal feeding operations. Industry practices such as copper smelting, mining and coal burning also contribute to arsenic in our environment.

Human exposure to arsenic can cause both short and long term health effects. Short or acute effects can occur within hours or days of exposure. Long or chronic effects occur over many years. Long term exposure to arsenic has been linked to cancer of the bladder, lungs, skin, kidneys, nasal passages, liver and prostate. Short term exposure to high doses of arsenic can cause other adverse health effects,Potential links between arsenic and cardiovascular disease, diabetes and other cancers are being studied, but the evidence to date is not conclusive.
The maximum level for arsenic in water is 0.010 milligrams per liter (mg/L).

ODOR

Well water will sometimes develop an odor in the water, which is evidence of a problem.
The maximum level for odor in well water is 3 O.U.
Your test results will either be ND = Not Detected or D = Detected

TURBIDITY

Turbidity is a measure of the cloudiness of water. It is used to indicate water quality and filtration effectiveness (e.g., whether disease-causing organisms are present). Higher turbidity levels are often associated with higher levels of disease-causing microorganisms such as viruses, parasites and some bacteria. These organisms can cause symptoms such as nausea, cramps, diarrhea, and associated headaches. They may also cause plugged piping or fouled water treatment equipment.
Turbidity levels should be less than 5 NTU’s (turbidity units) for clear, acceptable water.

AMMONIA

Ammonia is a colorless, pungent gaseous compound of hydrogen and nitrogen that is highly soluble in water. It is a biologically active compound found in most waters as a normal biological degradation product of nitrogenous organic matter (protein). It also may find its way to ground and surface waters through discharge of industrial process wastes containing ammonia and fertilizers. Ammonia has been used in municipal treatment systems for over 70 years to prolong the effectiveness of disinfection chlorine added to drinking water. The addition of ammonia enhances the formation of chloramines (which may create objectionable tastes), and it reduces the formation of chlorination by products which may be carcinogenic.
There is no EPA mandated Maximum Contaminant Level (MCL) for ammonia.

VOLATILE ORGANIC COMPOUNDS

No (VOCs) should be detected in well water, PERIOD. The presence of VOCs may be indicative of a well contaminated by petroleum products, industrial solvents or chemical byproducts. The presence of these compounds is potentially a health risk which can cause long-term adverse health effects.

VOCs are emitted as gases from certain solids or liquids. They are a group of commonly used chemicals (numbered in the thousands) that evaporate, or volatilize, when exposed to air. Since they dissolve many other substances, VOC’s are widely used as cleaning and liquefying agents in fuels, degreasers, solvents, polishes, cosmetics, drugs, and dry cleaning solutions. Concentrations of many VOCs are consistently higher indoors (up to ten times higher) than outdoors.

VOC’s are found at airports and service stations; machine, printing and paint shops; electronics and chemical plants; dry cleaning establishments; pesticides, building materials, furnishings and in household products. Paints, varnishes, and wax all contain organic solvents, as do many cleaning, disinfecting, cosmetic, degreasing, and hobby products.

When VOC’s are spilled or dumped, a portion will evaporate, but some usually soaks into the ground. In soil, the VOC’s can be carried deeper with percolating rainwater or melting snow. If they reach the water table, they can persist for years because the cool, dark, low-bacteria environment does not promote decomposition. If the VOC’s in the groundwater migrate to nearby wells, they can end up in your drinking water.
VOC contamination in your well water is a very serious heath concern.

PFAS – Per- and polyfluoroalkyl substances

Per- and polyfluoroalkyl substances (PFAS) are a group of man-made chemicals that includes PFOA, PFOS, GenX, and many other chemicals. PFAS have been manufactured and used in a variety of industries around the globe, including in the United States since the 1940s. PFOA and PFOS have been the most extensively produced and studied of these chemicals. Both chemicals are very persistent in the environment and in the human body – meaning they don’t break down and they can accumulate over time. There is evidence that exposure to PFAS can lead to adverse human health effects.

PFAS can be found in:

• Food packaged in PFAS-containing materials, processed with equipment that used PFAS, or grown in PFAS-contaminated soil or water.
• Commercial household products, including stain- and water-repellent fabrics, nonstick products (e.g., Teflon), polishes, waxes, paints, cleaning products, and fire-fighting foams (a major source of groundwater contamination at airports and military bases where firefighting training occurs).
• Workplace, including production facilities or industries (e.g., chrome plating, electronics manufacturing or oil recovery) that use PFAS.
• Drinking water, typically localized and associated with a specific facility (e.g., manufacturer, landfill, wastewater treatment plant, firefighter training facility).
• Living organisms, including fish, animals and humans, where PFAS have the ability to build up and persist over time.

Why are PFAS important?
PFAS are found in a wide range of consumer products that people use daily such as cookware, pizza boxes and stain repellants. Most people have been exposed to PFAS. PFAS can accumulate and stay in the human body for long periods of time. There is evidence that exposure to PFAS can lead to adverse health outcomes in humans. The most-studied PFAS chemicals are PFOA and PFOS. Studies indicate that PFOA and PFOS can cause reproductive and developmental, liver and kidney, and immunological effects in laboratory animals. Both chemicals have caused tumors in animals. The most consistent findings are increased cholesterol levels among exposed populations, with more limited findings related to:

• low infant birth weights
• effects on the immune system
• cancer (for PFOA)
• thyroid hormone disruption (for PFOS)

How are people exposed to PFAS?
There are a variety of ways that people can be exposed to these chemicals and at different levels of exposure. For example, people can be exposed to low levels of PFAS through food, which can become contaminated through:

• Contaminated soil and water used to grow the food
• Food packaging containing PFAS
• Equipment that used PFAS during food processing

People can also be exposed to PFAS chemicals if they are released during normal use, biodegradation, or disposal of consumer products that contain PFAS.  People may be exposed to PFAS used in commercially-treated products to make them stain- and water-repellent or nonstick. These goods include carpets, leather and apparel, textiles, paper and packaging materials, and non-stick cookware.

Drinking water can be a source of exposure in communities where these chemicals have contaminated water supplies. Such contamination is typically localized and associated with a specific facility, for example, an industrial facility where PFAS were produced or used to manufacture other products, or an oil refinery, airfield or other location at which PFAS were used for firefighting. 
PFOA, PFOS, and GenX have been found in a number of drinking water systems due to localized contamination.  You can view more information about exposures to PFAS through drinking water on our Drinking Water Health Advisories for PFOA and PFOS page.
EPA has established the health advisory levels at 70 parts per trillion. 

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