Parameters

SAMPLING PARAMETERS AND DESCRIPTIONS

pH

Values of pH in surface water outside acceptable ranges can indicate human impacts such as agricultural runoff, mining, or infiltration of untreated wastewater. Low pH is acidic and can cause corrosion of pipes, as well as increased dissolved metals concentrations in surface water. High pH is alkaline and can cause scale buildup in fixtures, bad taste, and reduce the effectiveness of chlorine disinfection, as well as increased metal concentrations in stream sediments.

The Environmental Protection Agency’s Secondary Standard* for pH in drinking water is 6.5-8.5. pH concentrations above this level give the water a slippery feel and soda taste, and lead to deposits. pH concentrations below this level give the water a bitter metallic taste and leads to corrosion.

For the purposes of this study, the graphical range for pH is 4-10 standard units. Detection limits for pH are between 0 and 14 standard units. pH was measured in the field using a portable YSI multiprobe and was also determined in the lab using EPA method 150.1.

Acidity

Low pH values indicate that surface water is acidic. High acidity values in surface water may come from several sources, such as mining and acid precipitation. Acid precipitation may cause the dissolution of aluminum in soils with poor buffering capacity, which in turn causes acidity to increase in surface water when the soil enters the stream as runoff. As acidity increases, dissolved metal concentrations increase, which in turn may cause problems for aquatic life in streams and rivers.

For the purposes of this study, the graphical range for acidity is 0-1,000 mg/L as CaCO3. Detection limits for acidity are as low as 2 mg/L, with no upper value. Acidity was measured in the lab using EPA method 305.2.

Alkalinity

High pH values indicate that surface water is alkaline in nature and that the water has a greater neutralization capacity. Typically, a small to moderate amount of alkalinity in water is also important to have for the well-being of the organisms that live in the water body. However, too much alkalinity can be toxic to wildlife. High alkalinity can also cause impacts to humans, including scale buildup in fixtures, bad taste, and reduce the effectiveness of chlorine disinfection. Alkaline water may also impact irrigation if the alkalinity of the water is greater than the alkalinity of the surrounding soil.

For the purposes of this study, the graphical range for alkalinity is 0-1,000 mg/L as CaCO3. Detection limits for alkalinity are as low as 10.0 mg/L, with no upper value. Alkalinity was measured in the lab using EPA method SM-2320B.

Electrical Conductivity

Electrical conductivity is an indicator of dissolved metals. Some common metals that may be found in surface water include: iron, aluminum, calcium, magnesium, and others. High conductivity levels may be due to several different factors, including: untreated wastewater infiltration, mining, and agricultural runoff. High conductivity concentrations can be damaging to aquatic life because of increased salinity in the stream and possible smothering of the stream bottom.

The World Health Organization recommends electrical conductivity levels less than 250 µs/cm for drinking water.

For the purposes of this study, the graphical range for conductivity is 0-4,000 s/cm. Detection limits for conductivity are as low as 0 µs/cm, with an upper value of 9,999 µs/cm. Conductivity is measured in the lab using EPA method 120.1 and in the field with an YSI model 556 multiprobe.

Oxidation-Reduction Potential

ORP is the potential of a chemical species to acquire (reduction) or lose (oxidation) electrons. An oxidizing substance, such as chlorine, will have a positive ORP value, while a reducing agent, such as hydrogen sulfide, will have a negative ORP value. High or low ORP values could indicate the presence of large amounts of certain chemical species, such as chlorine or hydrogen sulfide, which may affect aquatic life.

For the purposes of this study, the graphical range for conductivity is -50-250 millivolts. There are no upper or lower detection limits for ORP. ORP is measured in the field with an YSI model 556 multiprobe.

Temperature

Temperature has a large impact on the biological activity of aquatic organisms. All aquatic organisms have a preferred temperature range. If the water temperature gets too far above or below this range, then the biological community becomes stressed and may have difficulty maintaining a stable population.

Temperature is also important because of its influence on water chemistry. The rate of chemical reactions generally increases at higher temperature, which in turn affects biological activity. Another important example of the effects of temperature on water chemistry is its impact on oxygen. Warm water holds less oxygen than cool water, so it may be saturated with oxygen but still not contain enough for survival of aquatic invertebrates or certain fish.

For the purposes of this study, the graphical range for temperature is -30-100 degrees Centigrade. There are no upper or lower detection limits for water temperature. Water temperature was measured in the field with an YSI model 556 multiprobe.

Total Dissolved Solids (TDS)

TDS is a general indicator of overall water quality. It is a measure of inorganic and organic materials dissolved in water. High levels of TDS in surface water may be due to several factors, including: sedimentation, mining, or storm water runoff. Increased TDS may impart a bad odor or taste to drinking water, as well as cause scaling of pipes and corrosion.

The Environmental Protection Agency’s Secondary Standard for TDS of drinking water is 500 mg/L. TDS levels above this standard increase hardness, color the water, give it a salty taste, and lead to staining.

For the purposes of this study, the graphical range for TDS is 0-1000 mg/L. The lower detection limit for TDS is 10.0 mg/L and there is no upper detection limit. TDS was measured in the field with an YSI model 556 multiprobe and in the lab using Standard Method SM-2540C.

 

Total Suspended Solids (TSS)

TSS, or turbidity, is the measure of the suspended particles in the water column. High levels of turbidity can come from many sources, such as urban runoff, soil erosion, wastewater discharges, agriculture, and removal of riparian zones. Increased levels of turbidity may cause water to darken, which in turn leaves less light for aquatic plants to perform photosynthesis. This in turn decreases the amount of dissolved oxygen being added to the water, which can affect aquatic organisms that are higher on the food chain. Extreme levels of TSS can also clog fish gills.

The Environmental Protection Agency’s Primary Standard for turbidity of drinking water from conventional or direct filtration is 1 Nephelometric Turbidity Unit, and samples must test under 0.3 NTUs in at least 95 percent of the samples in any month. For drinking water using other filtration methods, the turbidity at no time can exceed 5 NTU’s. High turbidity levels are associated with higher levels of disease-causing microorganisms.

For the purposes of this study, the graphical range for TSS is 0-250 mg/L. The lower detection limit for TSS is 2.4 mg/L and there is no upper detection limit. TSS was measured in the lab using Standard Method SM-2540D.

Cations/Anions

Specific cations and anions will also be sampled as part of this project. Both dissolved and total concentrations will be determined for all species. Dissolved concentrations allow the researcher to infer more detailed water chemistry information, while total concentrations are used to promulgate and enforce water quality regulations.

Aluminum (Al)

Aluminum is the third most common element on Earth. In most forms, aluminum is not very soluble in water. However, low pH waters, such as those associated with mine drainage, may contain large amounts of dissolved aluminum due to dissolution of aluminum-containing minerals within the local geology. When aluminum precipitates within the water column, it is in the form of an aluminum hydroxide. Aluminum hydroxide may be very harmful to aquatic life due to smothering of the stream bed of the water body. Aluminum may also clog the gills of aquatic organisms if the concentration is high enough.

The Environmental Protection Agency’s Secondary Standard for Aluminum in drinking water is 0.05 to 0.2 mg/L. Aluminum concentrations above this level alter the color of the water.

For the purposes of this study, the graphical range for both dissolved and total aluminum is 0-20 mg/L. The lower detection limit for aluminum is 0.050 mg/L and there is no upper detection limit. Both total and dissolved aluminum is measured in the lab using EPA method 6010B.

Bromide (Br)

Bromide is a chemical element found in the halogen group. At room temperature, it is a reddish-brown liquid that is slightly soluble in water. Dissolved bromide comes from several sources, including surrounding geology, fluids used in gas well drilling, seawater infiltration, and industrial waste. Elevated levels of dissolved bromide may interfere with water treatment, as well as pose a possible increased cancer risk to humans and wildlife.

For the purposes of this study, the graphical range for both dissolved and total bromine is 0-5 mg/L. The lower detection limit for bromide is 0.020 mg/L and there is no upper detection limit. Both total and dissolved bromide is measured in the lab using EPA method 300.0.

Calcium (Ca)

Calcium is an element that is found naturally in water due to its abundance in the Earth’s crust. Large bodies of surface water, such as rivers, typically contain 1-2 mg/L of calcium. High levels of calcium in surface water mean that the water is hard, which helps aquatic life by buffering the pH of the water and protecting those organisms with gills from direct metal uptake. However, if calcium and hardness are too high, hardening of pipes and staining may occur.

For the purposes of this study, the graphical range for both dissolved and total calcium is 0-20 mg/L. The lower detection limit for calcium is 1.0 mg/L and there is no upper detection limit. Both total and dissolved calcium is measured in the lab using EPA method 6010B.

Chloride (Cl)

Chloride, a component of salt, is one of the common anions found in freshwater and thus chloride levels are directly related to conductivity.

Chlorides are common in many products associated with human activities. Chloride is a “mobile ion,” meaning it is not removed by chemical or biological processes in the soil and ground water. Increasing chloride levels or levels above expected natural background amounts can indicate impacts from human activities. Chloride is also a useful and reliable chemical indicator of river / groundwater fecal contamination, as chloride is a non-reactive solute and ubiquitous to sewage & potable water. Slight increases in chloride concentration can have a subtle impact on aquatic ecosystems, but most fish and other large aquatic organisms are not directly affected until concentrations reach 1,000 mg/l or more.

The Environmental Protection Agency’s Secondary Standard for Chloride in drinking water is 250 mg/L. Chloride concentrations above this level give the water a salty taste.

The lower detection limit for chloride is 0.062 mg/L and there is no upper detection limit. Calcium is measured in the lab using EPA method 300.

Iron (Fe)

Iron is the most abundant metal in the Earth’s core. It is found in a large range of compounds in either a +2 or +3 oxidation state. It is also very important to humans and other organisms, as it is partially responsible for transporting oxygen through the bloodstream. Iron is easily dissolved in water and can be found naturally occurring in water bodies. High levels of precipitated iron oxides may cause smothering of stream bottoms and plugging of organism’s gills.

The Environmental Protection Agency’s Secondary Standard for Iron in drinking water is 0.3 mg/L. Iron concentrations above this level give the water a rusty color, metallic taste, sediment, and leads to reddish or orange staining.

For the purposes of this study, the graphical range for both dissolved and total iron is 0-20 mg/L. The lower detection limit for iron is 0.070 mg/L and there is no upper detection limit. Both total and dissolved iron is measured in the lab using EPA method 6010B.

Magnesium (Mg)

Magnesium is found in large concentrations in both the Earth’s crust and the human body. It is highly soluble in water, and is the third most abundant element in sea water. Concentrations of magnesium in freshwater vary according to surrounding geology. Along with calcium, magnesium concentrations are used to determine water hardness. High concentrations of magnesium cause similar problems to high concentrations of calcium, including staining and hardening of pipes and fixtures.

For the purposes of this study, the graphical range for both dissolved and total magnesium is 0-20 mg/L. The lower detection limit for magnesium is 0.20 mg/L and there is no upper detection limit. Both total and dissolved magnesium is measured in the lab using EPA method 6010B.

Manganese (Mn)

Manganese is commonly found in soil in its oxide form (pyrolusite). It is used in the steel making process, and is also an essential nutrient for most organisms. High concentrations of manganese in humans can cause many different health problems, including Parkinson’s disease and bronchitis. Manganese is also soluble in water, with large concentrations causing health problems in aquatic life. Manganese can also bioaccumulate through the food chain, causing top predators to have unhealthy levels of manganese in their bodies.

The Environmental Protection Agency’s Secondary Standard for Manganese in drinking water is 0.05 mg/L. Manganese concentrations above this level give the water a black to brown color, black staining and a bitter metallic taste.

For the purposes of this study, the graphical range for both dissolved and total manganese is 0-20 mg/L. The lower detection limit for manganese is 0.0050 mg/L and there is no upper detection limit. Both total and dissolved manganese is measured in the lab using EPA method 6010B.

Sodium (Na)

Sodium is a very common element found in rocks and soils. It is needed for all life forms to aid in the transmission of nerve impulses. It is also highly soluble in water and will react violently with water to form lye and hydrogen gas. Sodium is found naturally in freshwater bodies. Concentrations of sodium vary greatly, and are dependent on the surrounding soil and geology. Too much sodium can raise the pH level of a water body to the point where it is too high for certain species of aquatic life to survive.

For the purposes of this study, the graphical range for both dissolved and total sodium is 0-5 mg/L. The lower detection limit for sodium is 1.0 mg/L and there is no upper detection limit. Both total and dissolved sodium is measured in the lab using EPA method 6010B.

Sulfate (SO4-2)

Sulfate is a salt consisting of one sulfur atom and four oxygen atoms with an oxidation number of -2. Sulfate is naturally occurring in almost all water bodies. It usually comes from oxidation of sulfite ores, dissolution of sulfate minerals, shale, and industrial wastes. High concentrations of dissolved sulfate may give water an unpleasant taste and may be corrosive to plumbing. It may also have health effects including nausea and diarrhea.

The Environmental Protection Agency’s Secondary Standard for Sulfate in drinking water is 250 mg/L. Sulfate concentrations above this level give the water a salty taste.

For the purposes of this study, the graphical range for both dissolved and total sulfate is 0-200 mg/L. The lower detection limit for sulfate is 0.062 mg/L, and there is no upper detection limit. Both total and dissolved sulfate is measured in the lab using EPA method 300.0.

Sulfur (S)

Sulfur is a non-metal that is a yellow solid at room temperature. Sulfur is found in many different minerals and is extracted by melting the surrounding rock and collecting the molten sulfur. It may also be produced from hydrogen sulfide. It is a required nutrient for life on Earth and it is an essential building block of cells. It is insoluble in water. However, high concentrations of sulfur-containing compounds, such as sulfate, may be found in water due to human activities, such as mining.

For the purposes of this study, the graphical range for both dissolved and total sulfur is 0-20 mg/L. The lower detection limit for sulfur is 0.05 mg/L, and there is no upper detection limit. Both total and dissolved sulfur is measured in the lab using EPA method 200.7.

*Secondary Standards are non-mandatory water quality standards for 15 contaminants that do not pose a risk to public health.