Water Quality - The chemical, physical, and
biological characteristics of water with respect to
Solution - A gas, liquid, or solid dispersed
its suitability for a particular purpose. The same
homogeneously in a gas, liquid, or solid.
water may be of good quality for one purpose or
use and bad for another, depending on its
Temperature - (1) The thermal state of a substance
characteristics and the requirements for the
with respect to its ability to communicate heat to
its environment. (2) The measure of the thermal
state on the arbitrarily chosen numerical scale,
Water Table - The upper surface of a zone of
usually centigrade or Fahrenheit.
saturation (in ground water) where the aquifer is
not confined by an overlying impermeable
Total Dissolved Solids - All of the dissolved solids
in a water. TDS is measured on a sample of water
that has passed through a very fine mesh filter to
Well - An artificial excavation that derives water
remove suspended solids. The water passing
from the interstices of the rocks or soil which it
through the filter is evaporated, and the residue
represents the dissolved solids.
Treated Water - Water that has undergone
processing such as sedimentation, filtration,
softening, or disinfection and is ready for con-
sumption. Included is purchased potable water
which is retreated (chlorinated or fluoridated).
Does not imply potability until inspected by
PVNTMED personnel and approved by the
Turbidity - (1) A condition in water caused by the
presence of suspended matter resulting in the
scattering and absorption of light rays. (2) A
measure of fine suspended matter in liquids. (3)
An analytical quantity usually reported in arbitrary
turbidity units determined by measurements of
Turbidity Units - Turbidity units are a measure of
the cloudiness of water. If measured by a
nephelometric (deflected light) instrumental pro-
cedure, turbidity units are expressed in
nephelometric turbidity units (NTU) or simply TU.
Those turbidity units obtained by visual methods
are expressed in Jackson turbidity units (JTU)
which are a measure of the cloudiness of water.
They are used to indicate the clarity of water.
There is no real connection between NTUs and
JTUs. The Jackson Turbidimeter is a visual
method and the nephelometer is an instrumental
method based on deflected light.
Virus - The smallest (10 to 300 millimicrons in
diameter) form capable of producing infection and
diseases in humans or other large species. The
true viruses are insensitive to antibiotics. They
multiply only in living cells where they are
assembled as complex macromolecules using the
cells' biochemical systems. They do not multiply
by division as do intracellular bacteria.