ECMI Glossary of Water Related Terms
A B C D
E F G H
I J K L
M N O P
Q R S T
U V W X
Absorption is the process by which chemicals
in gaseous, liquid or solid phases are incorporated into and included within
another gas, liquid, or solid chemical. For example, sponges absorb water.
Acceptable daily intake (ADI) is the chemical
ingestion level determined by combining the maximum
No-Observed-Adverse-Effect-Level (NOAEL) with the addition of an uncertainty
(safety) factor. Chemicals with ADI levels usually are not considered or
suspected to be carcinogens. This classification results from toxicity data
collected during prolonged ingestion studies conducted on a number of animals.
Acidity -The base neutralizing capacity of a
water is known as acidity. Acids contribute to corrosiveness, influence chemical
reactions, and chemical/biological processes. Acidity is determined using a
titrametric or potentiometric method.
Acre-foot is the volume of water (325,851
gallons of water) required to cover one acre of land with 12 inches of water.
Adsorption is the adherence of gas molecules,
ions or solutions to the surface of solids. For example, odors from freezers and
refrigerators are adsorbed to baking soda.
Advection is the process by which chemicals
and heat are transported along with the bulk motion of flowing gas or liquid.
For example, nitrates move through soils and aquifer formations due
predominantly to the bulk motion or movement of water.
Alkalinity: The acid neutralizing capacity of
a water is known as alkalinity. For surface waters alkalinity has been called
"The Protector of the Stream", since the alkalinity of the water rests sudden
changes in the pH of the stream associated with the influx of acid deposition,
water containing organic acids, groundwater discharges or industrial wastes.
Most surface waters have alkalinity’s < 200 mg
CaCO3/L, but in limestone areas the alkalinity’s can be greater than 1000 mg
CaCO3/L. In some cases, pristine surface water have very low alkalinity’s and
therefore they would be adversely impacted by acid mine drainage and acid rain.
The alkalinity of precipitation can be from 1 to about 10 mg CaCO3/L. Typically
the best alkalinity for aquatic life is between 100 and 120 mg CaCO3/L.
Alkalinity is determined using a titrametric or potentiometric method.
Aluminum(Al): There is no published Maximum
Contaminant Level (MCL), but 0.2 mg/L is considered safe. Elevated aluminum is
believed to be associated with forms of dementia, such as: Alzheimer’s.
Ammonia (NH4): There is no MCL established
for ammonia. Ammonia is very toxic to fish and aquatic life. Ammonia
concentrations of 0.06 mg/L can cause gill damage in fish and 0.2 mg/L is lethal
to trout. Concentrations in excess of 0.1 mg/L suggest domestic or agricultural
sources of waste.
Anion is a negatively charged chemical.
Nitrate and chloride (Cl-) are examples of anions.
Anion exchange is the chemical process where
negative ions of one chemical are preferentially replaced by negative ions of
another chemical. In water treatment, the net effect is the removal of an
unwanted ion from a water supply. For example, some municipalities are
installing anion exchange systems to remove
nitrate from their water
Antimony (Sb): The maximum contaminant level
is 0.006 mg/L. Elevated levels of antimony can increase blood cholesterol and
decrease blood glucose.
Aquifer is the saturated underground
formation that will yield usable amounts of water to a well or spring. The
formation could be sand, gravel, limestone or sandstone. The water in an aquifer
is called groundwater. A saturated formation that will not yield water in usable
quantities is called an aquiclude. Most Pennsylvania aquifers may be
categorized into confined and unconfined aquifers.
Confined aquifer (artesian aquifer) is
the saturated formation between low permeability layers that restrict
movement of water vertically into or out of the saturated formation. Water
is confined under pressure similar to water in a pipeline. Drilling a well
into this type of aquifer is analogous to puncturing a pressurized pipeline.
In some areas confined aquifers produce water without pumps (flowing
artesian well). When pumping from confined aquifers, water levels often
change rapidly over large areas. However, water levels will generally
recover to normal when pumping ceases.
Unconfined aquifer (water table aquifer)
is the saturated formation in which the upper surface fluctuates with
addition or subtraction of water. The upper surface of an unconfined aquifer
is called the water table. Water, contained in an unconfined aquifer, is
free to move laterally in response to differences in the water table
Arsenic (As): The MCL for arsenic is 0.05
mg/L. Arsenic is highly toxic and its prevalence is due to the natural
occurrence of this metal and past use of arsenic in pesticides. Arsenic
poisoning typically makes people feel tired and depressed and this poisoning is
also associated with weight loss, nausea, hair loss, and marked by white lines
across your toenails and fingernails. For freshwater the concentration should be
less than 0.05 mg/L.
Artificial recharge is the unnatural addition
of surface waters to groundwater. Recharge could result from reservoirs, storage
basins, leaky canals, direct injection of water into an aquifer, or by spreading
water over a large land surface.
Barium (Ba):The MCL is 2 mg/L. Barium can
increase blood pressure.
Beryllium (Be): The MCL is 0.004 mg/L and it
can cause intestinal lesions.
Baseflow is that part of streamflow derived
from groundwater flowing into a stream.
Biological Oxygen Demand (BOD) : BOD is
typically reported as 5 day BOD and ultimate BOD at 20 C and reported as
milligrams of oxygen consumed per liter (mg O/L). BOD 5 is used by regulatory
agencies for monitoring wastewater treatment facilities and monitoring surface
water quality. BOD is the biochemical oxygen demand of the water and it is
related to the concentration of the bacterial facilitated decomposable organic
material in the water. A sample with a 5 day BOD between 1 and 2 mg O/L
indicates a very clean water, 3.0 to 5.0 mg O/L indicates a moderately clean
water and > 5 mg O/L indicates a nearby pollution source. BOD is a laboratory
test that requires a oxygen sensing meter, incubator, nitrifying inhibitors, and
a source of bacteria.
Cadmium (Cd): The MCL for cadmium is 0.01
mg/L. Cadmium poisoning is associated with kidney disease and hypertension and
possibly mutations. For freshwater the concentration should be less than 0.0004
Calcium (Ca): No specific recommendation, but
high calcium is associated with hardness, total dissolved solids problems and
can cause aesthetic problems.
Capillary fringe is a zone of partially
saturated material just above the water table. The depth of the fringe depends
upon the size and distribution of the pore spaces within the geologic formation.
Cation is a positively charged chemical. For
example, calcium (Ca+2), and Magnesium (Mg+2) are cations.
Cation exchange is a process where positively
charged ions of one chemical are preferentially replaced by positive ions of
another chemical. For example, water softeners replace Ca+2, and Mg+2
ions with the sodium (Na+2) ion.
Chloride (Cl): It is one of the major anions
found in water and wastewater. The recommended maximum contaminant level is 250
mg/L, since the chloride ion imparts a salty taste to the water. If ions of
Calcium and Magnesium are present, the chloride ion may not impart a salty taste
until over 1000 mg/L. In addition to human and animal waste, sources of chloride
can include natural geological formations, road salt storage and applications,
oil / natural base drilling, and saltwater intrusions. High levels of chloride
can attack and weaken metallic piping and fixtures and inhibit the growth of
vegetation. Chloride ion is detected using a titrametric or potentiometric
Chlorine: Chlorine in one of a number of
forms is added to water to destroy or deactivate disease-causing microorganisms
and is the mostly widely used disinfectant in the United States. Elevated
chlorine levels can great aesthetic problems (strong taste and odor) and if
organic matter is present it can result in the creation of trihalomethanes,
which are potentially carcinogenic with target organs including the liver and
Chemical Oxygen Demand (COD): COD is used as
a measure of the oxygen equivalent of the organic matter content of the sample.
Only the organic matter that is susceptible to oxidation by strong chemical
oxidant. COD is typically used when there are industrial wastewater sources,
comparing biological to chemical oxidation in the selection of treatment process
and performances, or depending on the waste stream it can provide insight into
the concentration of reduced inorganic metal inorganic, such as ferrous iron,
sulfide, and manganese. Chromium (Cr): The MCL is 0.05 mg/L. The impact of
chromium is not clearly defined, but it is known to adversely impact aquatic
Conductivity:The theoretical definition of
conductivity is the "reciprocal of the resistance of a cube of a substance 1 cm
on a side at a specified temperature". Typically the units of measure are
microhms/cm (uohms/cm) or microsiemens/cm (uS/cm). Conductivity or specific
conductance is a measure of the ability of a fluid to carry a charge which is
directly related to the concentration of dissolved substances. As the total
dissolved substances in the water increases, the conductivity of the water also
increases. For More information see Total Dissolved Solids.
Cone of depression is a depression in
groundwater levels around a well in response to groundwater withdrawal or
Contaminant is any unnatural biological,
chemical, physical, or radiological substance or matter contained in water. Tri-chloroethylene
(TCE) is a synthetic cleaning solvent sometimes found in groundwater near
Copper (Cu): The MCL is 1 mg/L. At 1 mg/L,
the water may taste bitter and is highly toxic and may disrupt the metabolic
processes, especially for children. For freshwater the concentration should be
less than 0.036 mg/L.
Deep percolation is the movement of water
below the maximum effective plant root zone.
Denitrifying Bacteria: In the process of
nitrification of wastewater, the two key bacteria of ecological importance are
nitrosomonas and nitrobacteria. These bacteria facilitate "catalyze" the
reactions. Nitrosomonas results in the removal of three pairs of electrons from
ammonia facilitating the formation of nitrite and nitrobacteria removes to
electrons from nitrite to form nitrate. The bacteria responsible for
denitrification are autotrophic and heterotrophic facultative anaerobes.
Monitoring for denitrifying bacteria is typically done to monitor the
performance of denitrification systems.
Diffusion is a process where heat or
chemicals are transported in response to differences in chemical concentration
or temperature. Movement is from high concentration (or temperature) to low
concentration (or temperature). This process could involve liquids, gases and
Discharge area is an area where groundwater
moves toward or is delivered to the soil surface. Groundwater can flow into
springs, or seeps; contribute baseflow to streams; or provide supplemental water
for plant use.
Dispersion is the process whereby a chemical,
contained in water, deviates from the path that would be expected due to bulk
flow. In the process the chemical is mixed with surrounding liquids, causing its
concentration to be reduced.
Distillation is a two-stage water treatment
method: 1) the liquid is boiled, producing water vapor; 2) the water vapor is
condensed, leaving most contaminants behind. Distillation can be used to remove
inorganic chemicals, some non-volatile organic chemicals, and bacteria.
Drawdown is a lowering of the groundwater
surface caused by withdrawal or pumping of water from a well. It is the
difference between the static water level and the pumping water level in a well
pumped at a constant flow rate.
Drainage is the process of transporting
surface water over a land area to a river, lake or ocean (surface drainage), or
removal of water from a soil using buried pipelines that are regularly spaced
and perforated (subsurface drainage).
Effluent is the discharge of a contaminant or
contaminants with water from animal production or industrial facilities or waste
water treatment plant.
Erosion is the process or series of processes
that removes soils, crop residues, and organic matter from the land surface in
runoff waters, or by wind. Water droplets begin the erosion process by detaching
soil particles. Runoff waters transport the detached particles to local and
regional streams or lakes. Soil erosion represents the single largest source of
nonpoint pollution in the United States.
Eutrophication is the process of surface
water nutrient enrichment causing a water body to fill with aquatic plants and
algae. The increase in plant life reduces the oxygen content of the water.
Eutrophic lakes often are undesirable for recreation and may not support normal
Evapotranspiration (ET) is the process of
changing soil water into water vapor through the combination of soil evaporation
and plant water use, or transpiration.
Field capacity is the amount of water a soil
contains after rapid drainage has ceased. It is the water content following a
period of gravity drainage without the addition of water.
Fecal coliform is a portion of the coliform
bacteria group originating in the intestinal tract of warm-blooded animals that
pass into the environment as feces. Fecal coliform often is used as an indicator
of the bacteriological safety of a domestic water supply.
bacterial densities will be determined using the membrane filtration technique.
The MF procedure uses an enriched lactose medium and an incubation temperature
of 44.5 + 0.2oC. Fecal coliform is bacteria typically found in the feces of warm
blooded mammals. Fecal coliform colonies produced by the M-FC medium are blue,
while non-coliform colonies are pale yellow, gray, or cream color. Since fecal
coliform is found in mammalian waste, it is recommended that fecal coliform be
absent from potable water.
Fecal Streptococcus:The fecal streptococcus
group consists of a number of species of the genus Streptococcus, such as: S.
faecalis, S. faecium, S. avium, S. bovis, S. equinus, and S. gallinarum.
Fecal Streptococci are typically found in the gastrointestinal tract of warm
blooded animals. Due to the variation in survival rates the ratio of FC/FS
should not be used as a means of differentiating human and animal sources of
bacterial contamination. Fecal streptococcus colonies produced by the KF-Streptococcus
broth are red. For potable water, the fecal streptococcus should be absent.
Gaining stream (effluent stream) is a stream
or portion of a stream where flow increases because of discharge from
Grains per gallon is a unit of measurement
often used to describe water hardness. One grain per gallon is approximately
equal to 17 ppm of various cations.
Groundwater (sometimes written as two words)
is water that occupies voids, cracks, or other spaces between particles of clay,
silt, sand, gravel or rock within the saturated formation.
Groundwater mining is the removal of
groundwater from an aquifer in excess of the rate of natural or artificial
recharge. Continued groundwater mining reduces the groundwater supply until it
is no longer an economical source of water.
Groundwater recharge is the process where
water enters the soil and eventually reaches the saturated zone. Recharge varies
from place to place due to the amount of rainfall, infiltration, and surface
Hardness: The hardness of a water is a
measure of the concentration of the multivalent cations (positively charged
particles) in the water, but primarily it is equivalent to the calcium and
magnesium concentration of the water. Hardness is typically reported as mg /L as
CaCO3 (calcium carbonate), but it may also be reported as grains per gallon (1
gpg (US) = 17.12 mg CaCO3/L ). Hardness Classification: Soft: 0 to 17 mg
CaCO3/L; Slightly Hard: 17 to 60 mg/L; Moderately Hard 60 to 120 mg/L; Hard 120
to 180 mg/L; and Very Hard > 180 mg/L. For more information visit the
Health advisory level (HAL) is a
non-regulatory health-based chemical concentration in drinking water that
results in no adverse health risks when a given amount of water is ingested over
exposure periods ranging from one day to a lifetime.
Heterotrophic plate count is a procedure for estimating the number of live
heterotrophic bacteria in the water. Colonies may form in pairs, colonies,
clusters or single cells, which can be termed as "colony-forming units". The
colonies are relatively small/compact and do not encroach on each other. This
procedure can accommodate volumes of sample or diluted < 1.0 ml. Test is
typically performed in high purity water, pilot treatment facility performance
evaluations, and pilot scale testing.
Hydraulic conductivity is a term used to
describe the ease with which water moves through soil or a saturated geologic
material. Hydraulic conductivity is influenced by the type of material
comprising the formation (sand, gravel, rock, limestone, sandstone, clay), the
slope of the water table, the type of fluid, and the degree to which existing
pores are interconnected.
Hydraulic gradient is the slope of the water
surface in an aquifer. The hydraulic gradient indicates the direction
groundwater will flow. Water always flows from higher water table elevations to
lower water table elevations. All other factors being equal, flow is greater
when the hydraulic gradient is steeper.
Hydrologic cycle describes the constant
movement of water above, on, and below the earth's surface. Processes such as
precipitation, evaporation, condensation, infiltration and runoff comprise the
cycle. Within the cycle, water changes forms in response to the Earth's climatic
Infiltration is the downward entry of water
into the soil. The infiltration rate is a function of surface wetness soil
texture, surface residue cover, irrigation application or precipitation rate,
surface topography and other factors.
Iron (Fe):The MCL is 0.3 mg/L. Iron is a
secondary drinking water standard and primarily regulated because of the
aesthetic problems associated with elevated iron concentrations.
No Available Definitions
No Available Definitions
Leaching is the removal of dissolved
chemicals from soil by the movement of a liquid (like water).
Lead (Pb):The MCL is 0.05 mg/L. Symptoms of
lead poisoning start as: abdominal pains, constipation, fatigue, depressed
appetite and decrease endurance, but long-term exposure may led to nerve and
kidney damage and anemia.
Losing stream (influent stream) is a stream
or portion of a stream that discharges water into the groundwater.
Low permeability layers include soil,
sediment or other geologic material that inhibit water movement. These layers
may serve as a base material, or confining beds for an aquifer. This may be
caused by a fragipan or silt clay horizon in the soil.
Magnesium (Mg): No specific recommendation,
but high calcium is associated with hardness, total dissolved solids problems
and can cause aesthetic problems.
Manganese (Mn):The MCL is 0.05 mg/L.
Manganese is primarily regulated because of the aesthetic problems associated
with elevated levels of manganese, i.e., a secondary drinking water standard.
Elevated manganese levels can disrupt the nervous system and regeneration of
hemoglobin. For freshwater the concentration should be less than 1.5 mg/L.
Maximum contaminant levels (MCLs) are legally
enforceable drinking water standards required by the Safe Drinking Water Act.
Standards set by the Environmental Protection Agency establish the maximum
permissible concentration of selected contaminants in public water supplies.
Contaminants are included on the list if they pose a public health risk. For
example, 10 ppm is the MCL for nitrate-nitrogen (NO³-N).
Maximum contaminant level goals (MCLGs) are
public drinking water standards that serve as nonenforceable goals for selected
contaminants contained in drinking water that pose no health risk to people over
a lifetime of exposure. A MCLG is a suggested level set by EPA as a guideline
for water utilities.
Mecury (Hg): The MCL is 0.002 mg/L for
organic mercury. Mercury has been associated with kidney disease. For freshwater
the concentration should be less than 0.00005 mg/L.
Methemoglobinemia or blue baby syndrome is
the condition that limits the oxygen-carrying capacity of red blood cells. The
condition occurs when bacteria in the digestive tract convert nitrate to
nitrite. Nitrite reacts with hemoglobin in the blood, producing methemoglobin
which cannot carry oxygen. The resulting oxygen starvation causes a bluish
discoloration of the body. The condition is largely confined to infants less
than 9 months old. Excessive amounts of nitrates may be ingested with water or
food. Often foods, such as fresh vegetables, are a major source of nitrates.
Nickel (Ni): MCL has not been established,
but for freshwater the concentration should be less than 0.1 mg/L. Element
detected using flame atomic absorption, no specific standard for nickel. Nickel
may cause dermatitis and nasal irritation.
Non-point source (NPS) pollution is the
source of surface or groundwater pollution originating from diffuse areas
without well-defined sources. The most common examples of NPS are chemicals that
enter surface water during runoff events from crop land and turfgrass, and soil
erosion from cultivated cropland and construction sites.
Ozone - A form of oxygen, O3. A powerful
oxidizing agent that is considered a pollutant in the lower troposphere but an
essential chemical in the stratosphere where it protects the earth from
high-energy ultraviolet radiation from the sun.
Ozone Disinfection - (see
Part-per-million (ppm) is a measure of
concentration of a dissolved material in terms of a mass ratio (milligrams per
kilogram, mg/kg). One part of a contaminant is present for each million parts of
water. For water analysis, parts per million often is presented as a mass per
unit volume (milligrams per liter, mg/l). There are one million milligrams of
water in one liter.
Perched water tables occur when a low
permeability material, located above the water table, blocks or intercepts the
downward flow of water from the land surface. Water mounds up above the
impermeable material, creating another saturated zone with a water table.
Permeability is the property of porous
materials indicating the ease with which liquids or gases will be transmitted
through a soil or other porous material. Permeabilities are not affected by
changing the type of liquid.
pH is a numerical measure of the acidity or
alkalinity of water. The pH scale ranges from 1 (acidic) to 14 (alkaline). A pH
of 7 is neutral.The technical definition of pH is that it is a measure of the
activity of the hydrogen ion (H+) and is reported as the reciprocal of the
logarithm of the hydrogen ion activity. Therefore, a water with a pH of 7 has
10-7 moles per liter of hydrogen ions; whereas, a pH of 6 is 10-6 moles per
liter. The pH scale ranges from 0 to 14. For more information please visit the
Phosphate (PO4): There is no MCL for
phosphate. In surface waters, phosphate is typically a limiting plant nutrient.
The recommend maximum concentration in rivers and streams is a concentration of
0.1 mg/L of total phosphate.
Point-of-entry (POE) treatment is the
treatment of all water entering a house, farmstead or other facility, regardless
of its intended use. Anion exchange is an example of POE treatment to remove
Point-of-use (POU) treatment is treatment of
water at the point it is used. A common example would be water treatment at the
kitchen sink for drinking and cooking uses. Reverse osmosis, distillation and
ozone are examples of POU treatment methods.
Point source (PS) pollution is the source of
surface or groundwater pollution that originates from a well-defined source.
Examples include: industrial effluent; large animal containment facilities; city
waste water treatment discharges; or chemical spills. Point sources commonly are
associated with pipeline discharges of some type.
Pollutant is any unwanted chemical or change
in physical property that renders a water supply unfit for its intended use.
Porosity is the ratio of the volume of open
spaces or voids to the total volume of a porous material. For example, a sand
and gravel deposit may have 20 percent porosity. Porosity determines the amount
of water that can be stored in a saturated formation. A saturated formation 100
feet thick with a porosity of 20 percent could store an equivalent water depth
of approximately 20 feet.
Potable water supply is a source of water
that can be used for human consumption.
Precipitation is the process where water
vapor condenses in the atmosphere to form water droplets that fall to the earth
as rain, sleet, snow or hail. Nebraska's long-term annual precipitation varies
from 16 inches in the west to 34 inches in the southeast. Annual deviations can
be greater than 30 percent.
Pumping water level is the water level in a
well when the pump is operating and water is being removed.
No Available Definitions
Recharge area is the area where water
predominantly flows downward through the unsaturated formation (zone) to become
Reference dose (RfD) is the maximum daily
exposure to a chemical that is judged to be without risk of adverse systemic
health effects over a person's lifetime. It formerly was called the Acceptable
Reverse osmosis (RO) is a water treatment
method used to remove dissolved inorganic chemicals and suspended particulate
matter from a water supply. Water, under pressure, is forced through a
semipermeable membrane that removes molecules larger than the pores of the
membrane. Large molecules are flushed into waste waters. Smaller molecules are
removed by an activated carbon filter.
Runoff is precipitation or irrigation water
that does not infiltrate but flows over the land surface toward a surface drain,
eventually making its way to a river, lake or an ocean.
Saturated formation (zone) is the portion of
a soil profile or geologic formation where all voids, spaces or cracks are
filled with water. No air is present. There may be multiple water-bearing
formations within a saturated formation. These water-bearing formations often
are separated by layers of clay or other impermeable layers.
Saturated thickness (zone) is the total
thickness of a saturated formation.
Seepage is the movement of water into or
through a porous material. Seepage occurs from canals, ditches, and other water
storage facilities. It sometimes is used to describe water escaping from
municipal landfill sites.
Selenium (Se):The MCL is 0.05 mg/L. Selenium
is associated with hair or fingernail loss, numbness of fingers and toes, and
circulatory problems. For freshwater the concentration should be less than 1.5
chlorination is the addition of chlorine for disinfecting a water supply
system including the well, and all distribution pipelines. Shock chlorination is
recommended when coliform bacteria are detected, or after system repairs.
Treated water, with a concentration of at least 200 ppm, is pumped throughout
the distribution system and allowed to set for at least 24 hours before flushing
with untreated water.
Silver (Ag):The MCL is 0.10 mg/L. Silver is
associated with causing discoloration of the skin. For freshwater the
concentration should be less than 0.0003 mg/L.
Sodium (Na):No MCL has been set. For
individuals on low sodium diets a general recommendation of 20 mg/L is used.
Specific capacity expresses the productivity
of a well. Specific capacity is obtained by dividing the well discharge rate by
the well drawdown while pumping.
Specific yield is the ratio of the volume of
water that will drain from a unit volume of aquifer by gravity flow.
Spring is the point of natural groundwater
discharge to a soil surface, river, or lake.
Static water level is the water level in a
well located in an unconfined aquifer when the pump is not operating. The static
water level is the surface of the water-bearing formation and typically is
synonymous with the water table.
Strontium (Sr):No MCL has been set, but the
element is analyzed using nitrous oxide -acetylene flame. The primary concern is
the presence of a radioactive form, known as Strontium-90.
Sulfate (SO4):The drinking water limit is 250
mg/L. Sulfate (SO4-2) is widely distributed in natural waters, but is typically
less than a few mg/L. In Northeastern Pennsylvania, the primary sources of
sulfate in surface waters and groundwater include: acid mine drainage, acid
deposition, and mineral oxidation. Standard set because of taste and aesthetic
problems and sulfates laxative effects.
Sulfite (SO3):May occur in boilers and boiler
feedwaters treated with sulfite to control dissolved oxygen levels, natural
waters containing industrial waste and in wastewater treatment plant effluents
using sulfur dioxide to dechlorinate the effluent.
Thallium (TI): The MCL is 0.002 mg/L, but a
MCL Goal is 0.0005. Thallium is associated with hair loss, changes in the blood,
and kidney, digestive, and liver problems.
Tin (Sn):No MCL has been established for tin.
Total Kjeldahl Nitrogen (TKN): There is no
MCl for total kjeldahl nitrogen. This parameter is used to measure the total
amount of organic nitrogen and is typically used for surface water and
groundwater investigations associated with domestic or agricultural
Transmissivity is the capacity of an aquifer
to transmit water. It is dependent on the water-transmitting characteristics of
the saturated formation (hydraulic conductivity) and the saturated thickness.
For example, sand and gravel formations typically have greater hydraulic
conductivities than sandstone formations. The sand and gravel will have a
greater transmissivity if both formations are the same thickness.
Total dissolved solids (TDS) is a water
quality parameter defining the concentration of dissolved organic and inorganic
chemicals in water. After suspended solids are filtered from water and water is
evaporated, dissolved solids are the remaining residue. Dissolved solids
commonly found in Nebraska water are calcium, magnesium, sodium, potassium,
bicarbonate, sulfate, chloride and silica. Total dissolved solid concentrations
depend on the geologic material water passes through in the saturated and
unsaturated zone, and the quality of the infiltrating water. Total dissolved
solid contents range from less that 100 ppm in the Small streams to greater than
1,000 ppm near the Susquehanna River in northeast Pennsylvania.
Turbidity: Turdidity is a measure of the
cloudiness or opaqueness of the water and is measured in nephelometric turbidity
units (ntu). The turbidity is influenced by the amount and nature of suspended
organic and inorganic material in water. Typically, the higher the concentration
of the suspended material the greater the turbidity. The value of 1 ntu is
recommend for drinking water, since higher turbidities could cause aesthetic
problems or inhibit the ability of a system to disinfect the water. The source
of turbidity could be fine sand, silt, and clay (i.e., soil separates); organic
material, particles of iron and manganese or other metal oxides, rust from
corroding piping, or carbonate precipitates. Turbidity measurements are
typically not made on surfacewater sources - see Total suspended solids.
Total Solids: The total amount of solids in
the sample, which includes: dissolved, suspended, and volatile.
Total Suspended Solids: A fixed volume of
sample is filtered through a preweighed and washed glass fiber filter. The
filter is then rinsed and dried at 103 to 105 C. The change in the weight of the
filter represents the weight of suspended material. This test is typically done
for surfacewater supplies and wastewater treatment plants. For drinking water,
turbidity is parameter that is typically monitored.
Total Dissolved Solids: Is determined by
filtering a measured volume of sample through a standard glass fiber filter. The
filtrate (i.e., filtered liquid) is then evaporated to dryness at a constant
temperature of 180 C. High total dissolved solids may effect the aesthetic
quality of the water, interfere with washing clothes and corroding plumbing
fixtures. For aesthetic reasons, a limit of 500 mg dissolved solids/L is
typically recommended for potable water supplies.
Total Volatile Solids: The residue for
previous testing is then ignited at a temperature of 500 C. The change in the
weight represents the amount of suspended or dissolved solids that are organic
in nature or volatilized. The parameter is typically used in wastewater
treatment plants because it provides an estimate of the organic matter content
within the waste stream.
Unsaturated formation (vadose zone) is the
soil or other geologic material usually located between the land surface and a
saturated formation where the voids, spaces or cracks are filled with a
combination of air and water.
Vanadium (V):Currently there is no specific
MCL for vanadium. Vanadium may cause respiratory problems and inhibition of Na
and K in ATP production.
Watersheds are regional basins drained by or
contributing water to a particular point, stream, river, lake or ocean.
Watersheds range in size from a few acres to large areas of the country.
Water table is the upper level of a saturated
formation where the water is at atmospheric pressure. The water table is the
upper surface of an unconfined aquifer.
No Available Definitions
Yeast and Molds: Yeast and molds are fungi. A
fungus is a colorless (i.e., lacking chlorophyll) plant with practically no
differentiation of cell structure. Yeast are small single-celled forms that
reproduce by budding or spore formation. Molds produce spores for both asexual
and sexual reproduction. Yeast and mold analysis is typically done on air-borne
samples and surface wipes.
Zinc (Zn): The MCL is 5 mg/L, because of
problems with the aesthetic quality due to the taste of zinc.