off the equipment on the washrack. It is your
responsibility to check with the person in charge of the
washrack to be sure this waste water is treated and not
discharged into the storm system. Provisions must be
made for pretreating or separating oil products and
cleaning solvents used at the washrack.
Pollution results from many activities, both
mankinds and natures. Water becomes polluted when
wastes from activities flow into a lake or stream in such
quantities that the natural ability of the water to cleanse
itself is lessened or completely destroyed.
Wastes are dumped into our waters daily. The
following list contains wastes and their sources:
. Sewage and other wastes come from cities and
industries and from pleasure boats, commercial ships,
. Nutrients (principally phosphates and nitrates)
leach from sewage, industrial waste, and land runoff.
. Complex chemicals are found in household
detergents, pesticides, herbicides, and wastes from
. Oil comes from ships ashore, offshore drilling
rigs, and shoreline industrial facilities.
l Crankcase oils are improperly disposed of by
auto service stations and home auto mechanics.
l Silt, sand, and debris come from city streets,
urban construction, highway construction, farm surface
erosion, and dredging from channel clearings.
. Salts flow from winter streets, field irrigation,
and industrial processes.
l Heater water from power projects, industrial
processes, and reservoir impoundments find their way
into our waters.
. Disease-causing bacteria comes mainly from
. Radioactive wastes come from a variety of
sources. These sources include the mining and
processing of radioactive ores, materials used in power
plants, industrial, medical, and other research, and
fallout during nuclear weapons testing.
l Mercury and other heavy metals frequently
escape from industrial plants.
. Drainage waste comes from animal feedlots and
meat processing plants.
These wastes have placed a serious strain on our
waste treatment systems, as well as on our waterways.
Some types of waste are difficult to remove. Other types
respond to conventional treatment, but there are not
enough treatment facilities to keep them out of our
waters. Solving the pollution problem is not easy, but it
must be solved if we are to have an adequate supply of
safe, clean water for future use.
OIL SPILLS ON WATER. An oil slick on the
surface of the water blocks the flow of oxygen from the
atmosphere into the water. This is harmful to fish and
other aquatic life. If the fish do not die from the oil
coating on their gills or from eating the oil or oil-laden
food, their flesh is tainted and they are no longer fit for
human consumption. Besides harming aquatic life,
drinking water can become contaminated by oil.
Drinking water from wells and surface storage facilities
is treated with chemicals to rid the water of harmful
bacteria. However, no amount of treatment can rid a
system of contamination from waste oil products. The
system must be abandoned.
Booming of spills has proved to be effective in
containing spills of liquids on relatively calm and
Because of ecological
considerations, booming has become an important
means of containing oil spills, even though more
effective equipment is now available.
Following confinement of oil spills on water,
various methods of removing the confined liquid have
been used. One method is the use of absorbents, such as
straw, plastics, sawdust, and peat moss. The absorbents
are spread on the surface of the spill and then collected
and burned on shore. Skimming devices operate on a
different principle and must include pumps and
separators. Power boats with skimmers on the bow
scoop up the oil and water and send them through an oil
separator and rollers to which only the oil adheres. The
oil is then removed by scraping or compression.
HARMFUL EFFECTS OF POLLUTED
WATERS. Several basic biological, chemical, and
physical processes affect the quality of water. Organic
wastes (natural products, such as food, paper, and
human waste) decompose by bacterial action. Bacteria
attack wastes dumped into rivers and lakes, using up
oxygen in the process. Fish and other aquatic life need
oxygen. If the waste loads are so great that large amounts
of oxygen are spent in their decomposition, certain types
of fish can no longer live in that body of water. A