Deep Well Injection of Industrial Wastes
JOHN C. MANNING, President
HydroDevelopment, Inc.
Bakersfield, California
INTRODUCTION
Pollution of the natural environment by waste products has become one of
the major problems facing our modem industrial society. Human and industrial
wastes have been disposed of traditionally by dumping on the ground or by discharge to streams, lakes, or to the ocean. As quantities of wastes have increased
along with growing population and more advanced technology, the natural environment sometimes has been overloaded with waste products. The result is
pollution. And the only way to abate the pollution is to reduce the quantities of
wastes being discharged or to find new ways or new places to dispose of waste
products. With increasing attention being given to pollution abatement in recent
years, a number of innovations in waste disposal have been put into practice.
One of the most promising of these is the process of waste disposal by deep-well
injection.
At present there are more than 100 operating injection wells in the United
States. For general information on these wells the reader is referred to a report
by Dr. Don L. Warner entitled "Deep Wells for Industrial Waste Injection in the
United States: Summary of Data"; Federal Water Pollution Control Administration, Cincinnati, Ohio, Water Pollution Control Research Series Publication No.
WP-20-10, November, 1967. This publication also contains an excellent bibliography on deep well injection of industrial wastes.
In the process of waste disposal by injection, liquid wastes are pumped down
deep wells into porous rock formations far below the ground surface (see Figure
1). Here the waste mingles with natural formation waters (usually brines) and is
sealed forever from returning to the environment of life at the earth's surface.
Where natural conditions favor its use, this method has proven to be an efficient
and practical means for disposing of relatively small to moderate quantities of
poisonous or dangerous waste products. Before an injection disposal system can
be installed, however, a detailed geologic and hydrologic study must be made of
the proposed site.
FEASIBILITY STUDY
Although most industrial regions of the United States are situated on geologic
terrains that provide suitable subsurface sites for injection disposal, this is by no
means universally true. And before the injection method is selected at a particular location, a feasibility study must be made to determine the existence of
sursurface rock reservoirs capable of taking and holding the injected waste.
In order to carry out waste disposal by deep-well injection, the following
subsurface conditions are needed at the disposal site (Figure 1): 1) There must be
a porous and permeable rock formation (such as a sandstone or porous limestone)
to act as a disposal reservoir for the injected waste; 2) The disposal formation
should be extensive enough to offer a sizable waste reservoir, and it should be
deep enough to allow adequate injection pressures in the injection wells; 3) Na-
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