GROUND  WATER POLLUTION
FROM SUBSURFACE EXCAVATIONS
            UNITED STATES
      ENVIRONMENTAL PROTECTION AGENCY
         Washington, D. C. 20460

               1973

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                             PREFACE
    The Federal Water Pollution Control Act,  as amended
(33 U.S.C. 1251 et seq.; 86 et seq.; P.L. 92-500) instructs the
Administrator of the Environmental Protection Agency to issue
information including processes, procedures, and methods to
control pollution resulting from the disposal of pollutants in
wells or in subsurface excavations (Section 304(e)(D)).

    This report is issued pursuant to that legislative mandate
in an attempt to shed some light  on the problems  of the pollution
of underground water.
                                     /
                                          c?
                                  *uisell E. Train
                                   Administrator

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EPA 430/9 73 012
           GROUND  WATER  POLLUTION
       FROM  SUBSURFACE  EXCAVATIONS
        UNITED STATES ENVIRONMENTAL PROTECTION AGENCY
               Office of Air and Water Programs
        Water Quality and Non Point Source Control Division
                   Washington, D.C. 20460

                           1973
    For sale by the Superintendent of Documents, U.S. Government Printing OfflCfc, Washington, D.C. 2M02 • Price $2,25

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FOREWORD - WATER QUALITY



In order to avoid undesirable changes in ground water

quality, that quality must first be established.  Consider

the discussion of the term "quality" provided by P. H.

McGauhey (1968) .
    "The idea that  'quality'  is a dimension of water that
    requires measurement in precise numbers is of quite
    recent origin.  Ancient British common law...was content
    to state that the user of water was not entitled to
    diminish it in quality.  But the question of what
    constituted quality was neither posed nor answered.
    ...A precise definition of water quality lay a long way
    in the future.

    "More than half a century ago a Mississippi jurist said,
    •It is not necessary to weigh with care the testimony of
    experts -- any common mortal knows when water is fit to
    drink.* Today we find it necessary to enquire of both
    common mortal and water expert just how it is that we
    know when water is fit for drinking.  Moreover, in the
    intervening years, interest in the 'fitness1 of water
    has gone beyond the health factor and we are forced to
    decide upon its suitability for a whole spectrum of
    beneficial use involving psychological and social, as
    well as physiological goals.

    "Looking back on the history of water resource
    development, one is impressed that under pioneer
    conditions it was usually sufficient to define water
    quality in qualitative terms, generally as gross
    absolutes.  In such a climate, terms such as swampwater,
    bilgewater, stumpwater, blackwater, sweetwater, etc.,
    produced by a free combination of words in the English
    language, all conveyed meaning to the citizen going
    about his daily life.  'Fresh1 as contrasted with  'salt1
    water was a common differentiation arising from both
    ignorance and a limited need to dispel it.  If a ground

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or surface water was fresh, as measured by the human
senses rather than the analytical techniques of chemists
and biologists, it little occurred to the user that it
was any different than rainfall in producing crops."

As the author has noted elsewhere (McGauhey, 1961; 1965)

"A need to quantitate, or give numerical values to, the
dimension of water known as 'quality1 derives from
almost every aspect of modern industrialized society.
For the sake of man's health we require by law that his
water supply be 'pure, wholesome, and potable.' The
productivity and variety of modern scientific
agriculture require that the sensitivity of hundreds of
plants to dissolved minerals in water be known and
either water quality or nature of crop controlled
accordingly.  The quantity of irrigation water to be
supplied to a soil varies with its dissolved solids
content, as does the usefulness of irrigation drainage
waters.  Textiles, paper, brewing, and dozens of other
industries using water each have their own peculiar
water quality reeds.  Aquatic life and human recreation
have limits of acceptable quality.  In many instances
water is one of the raw materials the quality of which
must be precisely known and controlled.

"With these myriad activities...going on simultaneously
and intensively, each drawing upon a common water
resource and returning its waste waters to the common
pool, it is evident to even the most casual observer
that water quality must be identifiable and capable of
alteration in quantitative terms if the word is to have
any meaning or be of any practical use.

"Thus it is that those unwilling to go along with the
Mississippi jurist must express quality in numerical
terms.

"The identification of quality is not in itself an easy
task, even in the area of public health where efforts
have been most persistent.  For example, the great
waterborne plagues that swept London in the middle of
the nineteenth century pointed up water quality as the
culprit; yet it was another quarter of a century before
the germ theory of disease was verified, and more than
half a century before the water quality requirements to
                         11

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meet it were expressed in numbers.  Even in 19 OU, when
our Mississippi jurist spoke, children still died of
•summer sickness1 (typhoid) often ascribed to such
things as eating cherries and drinking milk at the same
meal; and scarcely a family escaped the loss of one of
its members by typhoid fever.  Yet when it came to
defining the water quality needed to avoid this, the
best we cculd do was to place on some of the 'fellow
travelers' of the typhoid organism numerical limits
below which the probability of contracting the disease
was acceptably small.  Nor has this dilemma been
overcome.  In 1965, an outbreak of intestinal disease at
Riverside, California, which afflicted more that 20,000
people and caused several deaths, was traced to a new
comer (Salmonella tyjDhimurium)  in a water known to be
safe by 'experts' watching the coliform index.  So once
again the search begins for a suitable description of
quality.

"A second dilemma which survived the struggles that
codified and institutionalized our concepts of water
quantity lies in the definition of the word 'quality.'
While the dictionary may suggest that quality implies
some sort of positive attribute or virtue in water, the
fact remains that one water's virtue is another's vice.
For example, a water too rich in nutrients for discharge
to a lake may be highly welcome in irrigation; and pure
distilled water would be a pollutant to the aquatic life
of a saline estuary.  Thus, after all the impurities in
water have been cataloged and quantified by the analyst,
their significance can be interpreted in reference to
quality only relative to the needs or tolerances of each
beneficial area to which the water is to be put.

"Shakespeare has said, 'The quality of mercy is not
strained...1 And Indeed it is not as long as mercy is
defined in qualitative terms.  One can but imagine the
problems which might arise if it were required that
justice be tempered with 1.16 quanta of mercy in one
case and 100 quanta in another.  Yet this is precisely
what confronts us in establishing measures of the
dimension of quality of water."
                        111

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References
    McGauhey, P.H., "Folklore in Water Quality  Standards,"
     SJkZii Engineering, Vol. 3, No. 6, New  York,  June
    (1965).

    McGauhey, P.H., "Quality - Water's Fourth Dimension,"
    Proceedings of the Water Quality Conference,  University
    of California, Davis, California, January 11-13  (1961) .
3.  McGauhey, P.H. , j?H3inee_rjLnc[ Management  of  W^ater Quality,
    McGraw-Hill Series insanitary  Science  and Water
    Resources Engineering, McGraw-Hill,  Inc.,  New  York,  New
    York  (1968) .
                              IV

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                          CONTENTS




                                                      Page




FOREWORD -WATER QUALITY                                 i






ILLUSTRATIONS                                         X






TABLES                                                Xi






                          PART ONE




            SOURCE IDENTIFICATION AND EVALUATION




INTRODUCTION                                            1




         Pollution Mechanisms                           2




         Current Involvement                          12




         Current Practices                            13




         Sources of Contaminants                      14




         Types of Contaminants                        16




         Methods of Pollutant Transport               17




         Magnitude cf Pollution                       18




         Prediction Methods                           18






    SUMMARY AND CONCLUSIONS                           21




         References                                   23

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                          PART TWO

         CONTROL METHODS, PROCESSES, AND PROCEDURES
                                                      Page

SECTION I - INTRODUCTION                               24

              Public Law 92-500                        24

         GROUND fcATER QUALITY AND POLLUTION            25

              Occurrence of Ground Water               27

              Control by Elimination of                29
                Pollution Sources


SECTION II - POLLUTION FROM WELLS                      31

         INDUSTRIAL WASTE INJECTION WELLS              31

              Current Situation                        34

              Environmental Consequences               42

              Contamination of Fresh Ground Water      43

              Contamination of Other Subsurface
                Resources                              46

              Earthquake Stimulation                   46

              Control Methods                          47

              Local Site Evaluation                    51

              Waste Evaluation                         57

              Well Construction and Evaluation         61

              Aquifer Response and Wastewater
                 Movement                              67

              Operating Program                        68
                             VI

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     Surface Equipment and Emergency
       Procedures                             69

     Monitoring Procedures                    72

     State Programs                           74


OTHER WELLS                                   80

     Petroleum Industry Wells                 80

     Geothermal Energy Wells                  86

     Wells for Injection of Sewage
       Effluent and Desalination Plant
       Brines                                 89

     Radioactive Waste Disposal Wells         90

     Gas Storage Wells                        91

     Water Wells                              93

     Dry Holes and Abandoned Wel}.s            95

     References                               96


INJECTION INTO FRESH WATER AQUIFERS          101

     Scope of the Problem                    101

     Environmental Consequences              105

     Nature of Pollutants                    106

     Pollution Movement                      110

     Examples of the Use of Injection
       Wells                                 113

     Control Methods                         116

     Monitoring Procedures                   120
                   Vll

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              References                              121


SECTION III - POLLUTION FROM OTHER SUBSURFACE
                EXCAVATIONS                           123

         LAGOONS, BASINS, AND PITS                    123

              Scope of the Problem                    125

              Potential Hazard to Ground Water        127

              Control Methods                         130

              Monitoring Procedures                   132

              References                              134

         SEPTIC SYSTEMS                               136

              Scope of the Problem                    136

              Environmental Consequences              139

              Control Methods                         142

              Monitoring Procedures                   147

              References                              150


         LANDFILLS                                    151

              The Matter Of Definition                151

              Environmental Consequences              152

              Leaching of Landfills                   156

              Nature and Amount of Leachate           160

              Control Methods                         167

              Monitoring Procedures                   173

              References                              175
                            vxn

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         SEWER LEAKAGE                                178

              Scope of the Problem                    178

              Causal Factors                          179

              Environmental Consequences              180

              Control Methods                         184

              Monitoring Procedures                   185


         TANK AND PIPELINE LEAKAGE                    186

              Scope of the Problem                    186

              Radioactive Wastes                      187

              History                                 188

              Leakage in the United States            188

              Environmental Consequences              191

              Causal Factors                          194

              Pollution Movement                      196

              Control Methods                         198

              Monitoring Procedures                   209

              References                              215


                             APPENDIX

ADMINISTRATOR'S DECISION STATEMENT NO. 5                I

RECOMMENDED DATA REQUIREMENTS FOR EVALUATION OF
 SUBSURFACE EMPLACEMENT OF FLUIDS BY WELL INJECTION     IV
                             IX

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                       ILLUSTRATIONS

Figure        Title

A        Geologic features significant in	   50
         deep waste-injection-well-site evaluation,
         and locations of industrial-waste injection
         systems (Warner, 1968) .

B        Schematic diagram of an industrial	   66
         waste injection well completed in
         competent sandstone (modified after
         Warner, 1965).

C        Diagram of domestic sewage disposal	  103
         system employing a disposal well in the
         middle Eeschutes Basin, Oregon
        (Sceva, 1968) .

D        Hypothetical pattern of flow of	  112
         contaminated water injected
         through wells into water table and
         artesian aquifers  (Deutsch, 1963).

E        Area contaminated by subsurface	  199
         gasoline leakage and ground water
         contours in the vicinity of Forest
         Lawn Cemetery, Los Angeles County,
         as of 1971  (Williams and Wilder, 1971) .

F        Experimental results from Switzerland on...  203
         the distribution of oil in soil as a function
         of time (Todd, 1973) .

G        Swedish two~pump method for removal of oil   206
         pollution from a well  (Todd, 1973).
H        Oil interceptor	  207
         ditch.

I        Oil skimming..	  208

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                           TABLES

Table         Tiii§                                   Page

1        Distribution of existing industrial. ......    37
         wastewater injection wells among the 22
         states having such wells in 1972
         (Warner, 1972) .

2        Distribution of injection wells by ........    37
         industry type  (Warner, 1972) .

3        Operational status of industrial ..........    38
         injection wells (Warner, 1972) .

U        Total depth of industrial injection .......    38
         wells (Warner,  1972) .

5        Rate of injection in industrial.. .........    39
         wells (Warner,  1972) .

6        Pressure at which waste is injected.......    39
         in industrial wells  (Warner,  1972) .
7        Type of rock used for injection ..... „ .....    UO
         by industrial wells (Warner, 1972) .

8        Age of injection zone of industrial .......    40
         wells  (Warner, 1972) .

9        Factors fcr consideration in the geologic     52
         and hydrologic evaluation of a site for
         deep-well industrial waste injection.

10       Factors to be considered in evaluating....    58
         the suitability of untreated industrial
         wastes for deep-well disposal.

11       Summary of information desired in... ......    64
         subsurface evaluation of disposal horizon
         and methods available for evaluation.

12       Selected chemical-quality characteristics    109
         of native water and tertiary treated
         injection water (Vecchiolo and Ku, 1972) .
                             XI

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13       Components of domestic solid waste	   154
         (expressed as percentages of total).

14       Landfill disposal of chemical process	   155
         wastes.

15       Composition of municipal refuse	   157

16       Leachate composition	   162

17       Change in leachate analysis with time..,..   165
         (Meichtry, 1971) .

18       Ground water quality	   173

19       Summary of interstate liquid pipeline	   192
         accidents for 1971 (Office of Pipeline
         Safety, 1972 ).

20       Range of annual pipeline leak losses	   193
         reported on DOT Form 7000-1 for the
         period 1968 through 1971.

21       Frequency of causes of pipeline leaks	   195
         in 1971 (Office of Pipeline Safety, 1972).

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                          PART ONE



            SOURCE IDENTIFICATION AND EVALUATION






INTRODUCTION








"Ground water quality" is the name of the game in a



discussion of subsurface excavations as sources of



pollution.  In rare instances pollution from subsurface



excavations moves directly to surface water bodies without



entering the ground water domain.  To the extent that ground



water moves to the surface, which is considerable, polluted



ground water causes surface water pollution, but it is the



alteration of the chemical, physical, biological and



radiological integrity of ground water that is the



overriding concern.








Identification of the nature of polluting excavations starts



from the premise that every hole in the ground, whether



natural or man-made, is a potential source of ground water



contamination.  A "well" is a particular type of subsurface



excavation rather than merely, "a place from which water



issues forth" as it was described in ancient England where



the word originated.

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Pollution_Mecbanisms



There are three basic mechanisms by which ground water



becomes polluted:







    1)    The natural filtering system of vegetation, soil,



         silt, sand, gravel and rocks that protects ground



         water is bypassed by polluting substances.







    2)    The natural filtering system is overwhelmed by a



         concentration of polluting substances beyond its



         capacity to handle them, or by substances that are



         unfilterable.







    3)    The hydraulic or chemical balance in the subsurface



         is altered so that polluting substances move to,



         within or between aquifers to change water quality.







    Case 1:  System bypassed







Whether a hole is natural, dug by hand, drilled, blasted,



mined or otherwise excavated; and whether a hole is intended



for the producticn of a resource, the emplacement of a



waste, the storage of a product, the collection of

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information or the emplacement of hardware; it penetrates at



least a portion of the surface filtering system, thus



providing a possible avenue for contaminants to bypass that



system.  The polluting substances that can and do enter



aquifers as a result of these activities include most of the



elements in the periodic table in nearly every combination



known to man.







Subsurface excavations may be grouped into categories based



on a description of the excavation:







    •    Wells and vertical, drilled holes:



         Includes water wells, oil wells, gas wells, dry



         holes, core holes, shot holes, stratigraphic tests,



         waste injection wells, product injection wells,



         secondary recovery injection wells, solution mining



         wells, dewatering wells and observation wells.







    •    Sanitary facilities:



         Includes septic tanks, cess pools, latrines and dry



         wells.







    •    Underground mines and tunnels:

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         Includes highway,  railroad and storage tunnels.








    •    Construction excavations:



         Includes piling holes, basement excavations,  river



         and harbor dredging,  and sand drains.








    •    Quarries and strip-mines:



         Includes rock quarries, sand pits,  gravel pits,



         strip mines and natural sinkholes.








    •    Burial vaults:



         Includes buried pipe lines and buried tanks.








    •    Pit silos and land fills.








A broader grouping, based on the intended use of the



excavations, is also useful in terms of ground water



pollution considerations.








    •    Extraction:



         Producing wells, mines, quarries, and sand and



         gravel pits.

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    •    Injection:



         Waste disposal, mineral recovery, secondary mineral



         recovery and product storage.







    •    Other:



         Dry holes, stratigrapbic tests, shot holes, core



         holes, construction excavations, burial vaults,



         sink holes etc.







The evaluation of the extent of the occurrence of potential



sources is a matter of a thorough physical inventory,



bearing in mind that subsurface pollution is a four



dimensional problem involving three dimensional space, and



time.   As an example, a waste injection well may introduce,



through a twenty centimeter diameter hole in the ground,



highly toxic materials into several subsurface reservoirs



that are more than a kilometer apart vertically but are



directly beneath that twenty centimeter surface area.  The



waste may be directed into a useless, salty aquifer at a



depth of 3800 meters below the land surface where it will



cause pollution in the strict sense of the word, as defined



in P.L. 92-500, but may cause no environmental problems anc



never again be detected in the biosphere.  However an

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excessive injection rate (volume divided by time)  can cause



pressures that will fracture the overlying rock, or the



cement around the well casing, or the casing itself and



permit the wastes to enter a fresh-water aquifer only two



hundred meters below the land surface.  Additional pollution



problems can result from the corrosive deterioration of the



well casing near the surface where water-table aquifers can



be polluted at depths of fifteen meters or less.  The



measurable effects of the change in water quality of the



3800 meter aquifer may last for centuries but may have no



adverse effects and never be known.  The pollution of the



200 meter aquifer, or the 15 meter aquifer, may occur at any



time during the waste injection, may be detected at anytime



from a few days to many years after the injection commences,



and may last for many decades, moving at a rate of less than



30 centimeters a year.







It is useful to establish priorities of consideration in the



initial stages of an inventory program so that aquifers are



dealt with in the order of their importance and sources of



massive pollution receive first consideration with the



effect on human health as the leading criterion.

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The nature of the sources of ground water pollution may be



established in any political, geographic, administrative or



hydrologic region by an inventory of: the regional



activities that make or use holes in the ground; the types



of holes used or made; their design and construction; and



their location.  The regional extent of such sources may



then be determined by an inventory, by category, of these



holes and the use made of them, followed by an analysis of



the data thus obtained.








The location of the hole in three dimensional space is



critical in that the likelihood and magnitude of ground



water pollution resulting from a properly constructed



subsurface excavation is largely dependent on the amount and



type of material between the aquifers and the contaminant at



its point of release.








Much relevant information must be developed to aid in



assessing the pollution potential of the most sophisticated



type of injection well injecting large volumes of various



hazardous materials.  It is unlikely that all of the



information considered to be relevant for the sophisticated



case would be required for many particular subsurface

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excavations, but the minimum location information required



for all the general cases would include the name and address



of the party responsible for the generation of the



contaminant, the location of the excavation in terms of



surface geography  (State, County, Survey, Section, Township,



Range, latitude, longitude and surface elevation with



respect to sea level)  the location of the contaminant in



terms of subsurface geology (depth of excavation, depth to



top and bottom of  aquifers, depth to bedrock, depth to top



and bottom of aquicludes, depth to top and bottom of



injection zone and types of rocks involved).







Design and construction details are necessary to evaluate



the excavations pollution potential.  These may range from



knowing whether or not an excavation is lined with a low



permeability material (in the case of an evaporation pond),



to the case of a waste injection well which would require



design and construction information such as specifications



for all strings cf casing and tubing, cement, pumps,



pressure monitoring equipment, injection rate monitoring



equipment, contingency equipment, and surface valves and



piping plus details of hole diameters, casing types, casing



lengths, casing seats, cementing program, contingency

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program, monitoring program, testing and completion programs



and geologic formations penetrated.








Case 2:  System overwhelmed








A hole in the ground is not required for this type of



pollution to occur, but the collection of pollutants in a



subsurface excavation does provide the ultimate



concentration of materials and can cause the filtering



system to fail  (in the case of materials that would



ordinarily be filtered out by the soil), or can cause a



concentration of unfilterable pollutants (such as phenols)



to move into aquifers.  settling ponds, evaporation ponds



and waste lagoons are among the offenders in this category.








Case 3:  Hydraulic or chemical balance altered








Any subsurface excavation that is used to move fluids into



or out of the ground will have an effect on the hydraulic



balance of the aquifers involved.  The effect may be so



slight as to be immeasurable or may be so great as to cause



the fluid in a porous formation to treak out into other



porous formations cr to the surface.

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Injected fluid need not be a pollutant to cause serious



ground water pollution.  For example, cooling water of



excellent chemical quality may be injected into an aquifer



containing salt water at its lower end in order to avoid



causing a damaging temperature rise in a surface stream.



The resulting pressure change can:







    •    Cause the salt water to move into fresh-water



         portions of the same aquifer and into water wells.







    •    Cause the salt water to move into other fresh-water



         aquifers and into water wells.







    •    Cause the salt water to move into surface-water



         bodies.







The extraction of fluid also alters the hydraulic balance



and can cause the irovement of subsurface pollutants in and



between aquifers and surface waters.  For example, a



municipal water-well field pumping many millions of liters



per day may cause seawater to move inland in an aquifer



several kilometers further than it normally appears and thus



pollute municipal wells and other wells in the vicinity.
                            10

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Likewise, an industrial well pumping high quality process



water from the top 15 meters of an aquifer can cause the



upward coning of deeper salt water in the same aquifer,



resulting in the pollution of the well supply.  These



effects are treated more fully in the discussion of "Salt-



Water Intrusion." 7 Pollution may also result from a similai



lowering of pressure in a confined aquifer, causing the



compression of an overlying confining bed and resulting in



the "wringing out" of highly mineralized water from the



confining bed into the aquifer.  Arsenic pollution is known



to have resulted from just such a situation.








Instances of ground water pollution have been noted that



were attributed to a waste injection-caused change in pH and



temperature (chemical balance alternation).  The pollution



resulted, not from concentrations in the aquifer of the



injected material, but from an "unloading effect" that



occurred when the sorptive characteristics of a formation



that had trapped a toxic waste constituent from some other



source were changed by exposure to the injected material and



the toxic constituent was released into the ground water.
                            11

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Current__Involvement



An inventory of the disposal of wastes into holes in the



ground can be commenced by investigating federal waste



disposal practices.  A 1960 inventory1 covering waste water



disposal practices, under the category "ground disposal,"



reports more than 11,000 such activities, most of which



involve subsurface excavations (septic tanks, cesspools,



subsurface disposal fields, privy vaults, chemical toilets,



sewage lagoons and wells).







Other government entities in the subsurface disposal



business include the State equivalents of the Federal



departments as well as the various regional, county,



township and city organizations that generate wastes.







The private sector also warrants consideration with special



attention being paid to the industries that use well



injection as a means of disposing of large volumes of



noxious and obnoxious wastes2.  These include power plants,



steel mills, metal plating establishments, waste treatment



plants, pharmaceutical laboratories, food processing plants,



paper mills, and the petroleum industry and its exploration,



production, refining and chemical manufacturing operations.
                            12

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Other private sector sources include real estate



developments, agricultural units, the operators of large



buildings and countless rural and vacation home sanitary



facilities.







Current Practices



The uses made of wells and other subsurface excavations for



the disposal of wastes range in terms of volume from nearly



27,000 kiloliters a day to less than 200 liters, and in



terms of health hazard, from dangerous  (e.g., certain



radioactive materials)  to benign (air conditioning cooling



water) .







The subsurface disposal of radioactive materials has



occurred on an operating or experimental basis in several



states.  The methods used or considered include pit burial,



well injection into high porosity, well injection into low



porosity formations and salt-mine entombment.







Brines produced in association with crude oil, natural gas



and steam are normally disposed of by well injection, often



into the rock formation and zone from which they were



extracted, but mere often either into a deeper, non-

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productive portion of the formation from which they were



extracted or intc seme other rock formation.  There are tens



of thousands of these wells in the oil producing states.



Man made-brines are also handled in a similar manner though



of course they, being produced at surface sources,  do not.



have a partially depleted underground reservoir to which to



return 3 .







Raw sewage, treated sewage and hot water resulting from



various cooling processes are also being disposed of by well



injection.  Much material of all kinds is thrown, spilled,



dumped, leaked or merely left "lying around" in rock



quarries, sand and gravel pits, and construction



excavations.
  .__  of_ Contaminants



Vast areas of the United States that produce crude oil and



natural gas are underlain by huge volumes of contaminated



ground water.  The exploration for and the exploitation of



fluid hydrocarbons involve multiple sources of



contaminants4.  The pre-drilling exploration activities



frequently include seismic surveys that make many holes in



the ground.  Exploration and production drilling make larger

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and deeper holes.  secondary and tertiary recovery



activities require the use of injection wells, as does the



disposal of brines.







The nations petrochemical industry in its production phase



also utilizes waste injection wells and settling pits, as do



steel mills, metal plating establishments, pharmaceutical



laboratories, feed processing plants, paper mills, oil



refineries, sewage-treatment plants, water-treatment plants,



certain agricultural cooperatives and geothermal power



producers.
                            15

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Types_Qfi Contaminants



Natural brines produced in association with crude oil and



natural gas are a type of contaminant with a varied and



complex chemistry4 that most commonly includes greater than



trace amounts of sodium, calcium, magnesium, potassium,



barium, strontium, iron, sulphur, bromine and dissolved



gasses such as carbon dioxide, hydrogen sulfide and methane.







Natural brines produced in geothermal exploitation are



similarly constituted but often contain much more lithium,



flourine, silica, arsenic and radioisotopes.







Man-made pollutants that are regularly introduced into the



subsurface through well injection or other means include



acids, chromates, phosphates, alcohols, sulphates, nitrates,



bromine, chlorine, tin, aldehydes, pyrrolidone, ketones,



phenols, potassium, acetates, benzene, cyclohexane, hydrogen



cyanide2 and many ethers  (identified and unidentified) that



are being pumped, dumped and spilled into the earth.



Sewage, with the associated bacteria and viruses, is also on



the list.
                            16

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Methods of Pollutant^Transgort



Pollutants in solution move away from wells and other



subsurface excavations into aquifers, or to the surface,



along the paths cf least resistance.  Commonly, the zone of



fluid movement from a well or other subsurface excavation is



a naturally occurring unconsolidated sand or gravel5 in



which fluid moves between the grains in a characteristic



manner that lends itself to rather precise mathematical



modeling which yields reasonably straightforward predictive



information.







Consolidated rocks usually exhibit more complex types of



porosity with fluid movement through solution-caused pores



or channels, or stress-caused joints and fractures.  In some



instances the movement is uniform and therefore predictable,



but in many instances it is not.  The same is true of man-



made fractures and channels (the result of high pressure



fluid injections, the injection of solvents and subsurface



explosions) .







Subsurface excavations are, in themselves, potential paths



for the vertical movement of fluids.  Uncased and poorly



cased holes provide direct avenues for the movement of
                            17

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pollutants from the surface to aquifers,  from waste



injection zones to the surface, and from waste injection



zones to other aquifers.   Excessive injection pressures



aggravate any tendency for fluid to escape through casing-



thread leaks, pinhole leaks or channels in the casing



cement.







Magnitude^of Pollution



Studies of the magnitude of ground water pollution have been



made by governmental and private groups including the



Envrionmental Protection Agency, the U.S. Geological Survey



and other Department of the Interior groups, the Atomic



Energy Commission, the American Asspciation of Petroleum



Geologists, the American Institute of Mining Engineers, the



Interstate Oil Compact Commission and many others.  The



EPA's "subsurface Water Pollution - A Selective Annotated



Bibliography," Part I, II and III lists hundreds and is



available from the EPA's Office of Water Program Operations,



Washington, D. C.  20U60 .







Prgdiction_Methgds



The problems of designing, constructing and operating



subsurface waste-disposal facilities properly are quite
                            18

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complex, requiring consideration of the interacting physical



and chemical character of: the construction and operating



materials, the wastes involved, the geologic formations that



will receive them, and the fluids naturally present in those



formations.







Various predictive techniques are useful in attacking the



problems that result from subsurface waste disposal and, as



with other subsurface problems, no one method will provide a



complete answer.







The basic tools for predicting the location and extent of



subsurface pollution are waste surveys and hydrogeological



studies, the former to determine the volume and nature of



the materials being introduced into the subsurface, and the



latter to assist in assessing the results; for example, the



existence of an operating steel mill guarantees the



accumulation of a certain amount of used pickling liquor



which, if it finds its way into a good quality surface or



subsurface water, is a pollutant.  The liquor may be



recycled for the removal of usable materials to the extent



that it is acceptable as a component of an authorized



effluent discharge to a surface stream.  It also may be
                            19

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piped,  untreated, to an injection well and placed



underground,  A waste survey indicating the existence of the



steel mill will thus alert investigators to a pollution



threat.  Such a survey will also establish similar threats



from a high concentration of Septic tanks, brine injection



wells,  food processing plants, and other waste generating



activities.







Existing hydrogeological studies made by private, municipal,



county, state or federal groups will often yield enough



information to establish the areas of likely ground water



contamination resulting from waste disposal activities.



Additional empirical evidence will come via complaints from



well and spring users whose water supplies have developed



taste,  odor, sediment or color problems.  Local health



records may also indicate ground water pollution.  A ground



water quality monitoring system may exist in the area and



yield precise information on the results of the disposal of



the waste.  Mathematical and analog modeling of the



subsurface excavation and the aquifers involved may



contribute quite reliable data on the fate of the wastes and



indicate where tc look for ground water pollution.  Various



geophysical investigations  (e.g., seismic surveys and well
                            20

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logging)  are often the most convenient way to reinforce both



empirical and theoretical investigations.







SUMMARY AND CONCLUSIONS







Ground water supplies a significant proportion of the total



amount of fresh water withdrawn* for use in the United



States (21.4% in 1970); it supplies more than 34% of the



nation's public water supply needs, more than 36% of the



crop-irrigation water withdrawn, and from 47% to 83% of the



total water withdrawals in eleven of our larger states.







As the control of discharges of pollutants into surface



waters becomes more effective, the temptation to go to



subsurface discharges becomes stronger.  An increased and



continuing awareness of what is being placed, intentionally



or inadvertently, in wells and other subsurface excavations,



and where it is going, is essential if we are to prevent the



widespread pollution of our ground water resources.







The use of subsurface excavations for the disposal of wastes



is growing, the types of materials so disposed of are



legion, and the placement and isolation of these materials
                            21

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so as to avoid adverse environmental impacts (particularly



ground water quality degradation)  is a difficult and



complicated problem.







The states, in order to avoid the long-term pollution of



huge quantities of usable water, must continue to devote



careful and expert attention to the protection of the



subsurface environment to assure their citizens of a



continuing supply cf good quality ground water at the least



cost.
                            22

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References

1.  U.S. Department of Health, Education, and Welfare, Waste
    Water Disposal Practices at Federal Installations as of
    December |I7 I960,  Vol. 54, 55, 56', 57, 58.

2,  Warner, Don. L., Survey of Industrial Waste Injection
    Wells, U.S. Geological Survey  (1972).  ~^~

3.  Research Committee, Interstate Oil Compact Commission,
    Production and Disposal of Oilfield Brines in the United
    States and Canada,  Interstate Oil Compact Commission,
    Oklahoma City, Ok., (1960).

4.  Collins, A. Gene, Oil and Gas Wells - Potential
    Polluters of the Environment? Water Pollution Control
    Federation Journal, Washington, D. C.  20016, Vol. 43,
    No. 12, pp 2383-2393 (Dec. 1971).

5.  Walton, William C., Groundwater Resource Evaluation,
    McGraw-Hill,  (1970).

6.  Murray, Richard C. and Reeves, Estimated Use of Water in
    the United States in 1970r  U.S.  Geological Survey,
    Washington, D.~c7, 20242  (1972) .

7.  Environmental Protection Agency,  Identification and
    Cgntrgl of Pollution from Salt Water Intrusion^
    Washington,~E.C. 20460(1973).
                            23

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                          PART TWO
         CONTROL METHODS, PROCESSES, AND PROCEDURES

                  SECTION I - INTRODUCTION
gublic Law 92-500



Section 304 (e)  of Public Law 92^500, the Federal Water

Pollution Control Act Amendments of 1972, provides that

    "The Administrator  (of EPA)...shall issue...within one
    year after the effective date of this subsection  (and
    from time to time thereafter) information including  (1)
    guidelines for identifying and evaluating the nature and
    extent of nonpcint sources of pollutants, and (2)
    processes,  procedures, and methods to control pollution
    resulting from (D) the disposal of pollutants in wells
    or in subsurface excavations.

The treatment of this topic is not intended to be

exhaustive, since this would take many volumes.  Rather, the

intent is to be as concise as possible, addressing those

aspects felt to be most important, with liberal use of

selected references to more detailed explanations.

-------
GROUND WATER QUALITY AND POLLUTION








The quality of ground water refers to its chemical,



physical, and biological characteristics.  All ground water



contains dissolved solids and possesses characteristics such



as temperature, taste, and odor.  Some contain pathogens



such as bacteria and viruses.  The natural quality of ground



water depends upcn its environment, movement, and source?and



in different localities, major contrasts in natural quality



can be noted.  Ground water temperatures may range from a



few degrees above freezing in cold climates to considerably



above the boiling point in thermal-spring sources, while



salinities may range from near zero in newly infiltrated



precipitation to several hundred thousand milligrams per



liter in underground brines.








For the purposes of this report, ground water pollution is



defined as the man-made or man-induced alteration of the



chemical, physical, biological, and radiological integrity



of ground water.  Such pollution is caused, as we would



expect, by the introduction into aquifers of pollutants.



Pollutants are defined in Public Law 92-500 to include,



among other things, all industrial wastes except, "water.
                            25

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gas, or other material which is injected into a well to



facilitate production of oil or gas, or water derived in



association with oil or gas production and disposed of in a



well, if the well used either to facilitate production or



for disposal purposes is approved by authority of the State



in which the well is located, and if such State determines



that such injection or disposal will not result in the



degradation of ground or surface water resources." The



particular use to which a ground water can be put depends,



of course, upon its quality.  However, the various criteria



defining the suitability of a ground water for municipal,



industrial or agricultural use are not considered in



describing pollution.  Instead, the measure of pollution is



the measure of the detrimental change in the given natural



quality of ground water.  This may take the form, for



example, of an increase in chloride content, of a rise in



temperature, or of the addition of pathogens.







Programs to control ground water pollution are based upon



the growing realization that both ground water and the



underground space in which it is stored are valuable natural



resources to be conserved by preventing, reducing, and



eliminating pollution.
                            26

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Occurrence of Ground Water



Ground water forms a part of the hydrologic cycle.  It



originates as precipitation or surface water before



penetrating below the ground surface.  Ground water moves



underground toward a natural discharge point such as a



stream, a spring, a lake, or the sea, or toward an



artificial outlet constructed by man such as a well or a



drain.








An aquifer is a formation, group of formations, or part of a



formation that contains sufficient saturated permeable



material to yield significant quantities of water to wells



and springs (USGS 1972).  The most common aquifers are those



consisting of unconsolidated alluvial materials such as



gravel, sand, silt, and clay.  Other important aquifers



occur in coal, sandstones, limestones, volcanic rocks and



other igneous rocks.








The water table is that surface in an unconfined water body



at which the pressure is atmospheric (USGS 1972).  Below the



water table the permeable soil or rock is saturated with



water.  Unconfined ground water is water in an aquifer that



has a water table, whereas confined ground water is under
                            27

-------
pressure significantly greater than atmospheric, and its



upper limit is the bottom of a bed of distinctly lower



hydraulic conductivity than that of the material in which



the confined water occurs (USGS 1972) .







Ground water typically flows at rates of from 20 centimeters



per year to 2 meters per day.  Above the water table the



flow direction is generally downward, but below the water



table in the main ground water body, the movement is lateral



and governed by the local hydraulic gradient.  Once a



pollutant is introduced into an aquifer it tends to move in



the same direction as the incorporated ground water and at a



velocity equal to or less than that of the ground water.



Pressure changes, in contrast, travel at or near sonic



speed.  With time and distance traveled, pollutants decrease



in concentration, resulting from dilution, filtration,



adsorption, precipitation, decay  (e.g., radioactive



isotopes), and death  (e.g., bacteria).  From a point source



of pollution, plumes of various shapes are often detected



extending downgradient within the aquifer and gradually



dissipating with distance.
                            28

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                       of __Polluticn_ Sources
For any source or cause of pollution, an obvious control



method would be to eliminate entirely the source or the



cause itself.  This method, however, is not possible in many



situations and thus becomes a trivial solution.  To



illustrate the point, one method for controlling pollution



from septic tanks would be simply to eliminate all septic



tanks.  To completely eliminate the millions of septic tanks



in the United States would require alternatives that are not



realistic or feasible.  These may include, for example:







    •    Installing sewer systems to replace septic tanks —



         economically infeasible in many rural areas.







    •    Replacing septic tanks with individual home waste



         treatment and desalination plants — technically



         and economically infeasible at the present time.







    •    Moving people to sewered areas -- socially,



         legally, and politically infeasible.







Thus, the control methods that are described for septic



tanks include not only the possibility of requiring sewers



but also deal with regulating their construction,  their
                            29

-------
location as regards subsurface conditions and topography,



their density, their operation, and their maintenance.  The



latter measures, while not eliminating ground water



pollution, will reduce it and will prevent it from exceeding



prescribed levels.







The suggestion that the source or cause of pollution be



eliminated is not repeated for each of the sources and



causes that are discussed.  In general, the control methods



that are suggested and discussed are those believed to be



realistic and feasible.  Clearly, the applicability of the



suggested methods will depend upon local situations.







In situations involving the intentional placement of



pollutants in subsurface excavations, control methods



involve measures to assure the isolation of the pollutants



from the biosphere.  The six steps essential to this end,



which are developed in this report, are:







    •    Siting               »    Monitoring



    •    Design               «    Abandonment



    •    Construction



    •    Operation
                            30

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             SECTION II - POLLUTION FROM WELLS
This section considers ground water pollution resulting from



the injection of fluids into the earth, the extraction of



fluids from the earth, and other aspects of ground water



pollution resulting from the construction and use of wells.



Primary emphasis is placed on the subsurface emplacement of



industrial wastes by well injection.  Wells for this



purpose, commonly referred to as "waste disposal wells," are



a relatively recent development and are becoming



increasingly popular as restrictions on the discharge of



noxious and obnoxious fluids to surface waters become more



stringent.
INDUSTRIAL WASTE INJECTION WELLS








The potential of wells for the subsurface disposition of



industrial wastes was recognized and exploited by at least



one company as early as 1928.   The extent of such use



outside the oil industry was small until the 1960»s when
                            31

-------
increasing emphasis on surface water polluton control



prompted companies to seek other alternatives for waste



water releases, one of which was well injection.







As of mid 1972 at least 246 such wells had been constructed



in the United States  (Warner, 1972).  This number is



relatively small, but the volume of waste involved, and its



potency, has caused considerable concern to be expressed



about the use of injection wells.  The technical reasons for



this concern include the following:
         Some of the wastes that are being injected contain



         chemicals that are relatively toxic and will



         persist indefinitely in the subsurface environment.







         Monitoring of the subsurface environment is quite



         difficult in comparison with monitoring of the



         surface.







         If contamination of usable ground water or other



         resources should occur, decontamination may be



         difficult or impossible to effect.
                            32

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Why should such wells be used at all in view of these and



other possible objections?  If the alternatives are examined



that are available for ultimate disposition of waste waters



containing dissolved inorganic chemicals, relatively



nondegradable dissolved organic chemicals, or combinations



of these, it is found that they are limited to disposal to



the ocean, disposal to the land surface, disposal to fresh



waters, storage, incineration, recovery of the chemicals for



reuse, or subsurface injection.  Of these alternatives,



subsurface injection may be the most satisfactory in some



cases.  The need for continuous reevaluation of the problem



of the ultimate disposition of such waste waters may become



even more pressing as a result of the goals stated in P.L.



92-500, the Federal Water Pollution Control Act Amendments



of 1972.







We will discuss trends in usage of industrial waste-



injection wells in the United States, the environmental



impacts of such wells, and methods for preventing ground



water pollution frcm such wells.
                           33

-------
Current Situation




An inventory of industrial waste-
-------
pharmaceutical companies, and about 25 percent by



refineries and natural gas plants.  These data



identify the dominant present, and probable future,



industrial users of injection wells.







About 80 percent of the wells that have been



constructed are presently operating or will be put



into operation.  Only 5 percent of wells that have



been constructed were initial failures and never



operated.  Thus, the success ratio of such wells is



very high.







About 75 percent of existing wells are between 800



and 1800 meters deep.  Less than 10 percent are



shallower than 300 meters.  This fact provides some



assurance of protection to usable ground water



resources.







About 70 percent of present wells inject less than



15 liters per second (200 gpm) and 86 percent less



than 30 liters per second (400 gpm).  This suggests



the rate that can be expected for most wells and
                   35

-------
         reduces the need to consider waste-water streams



         that exceed these amounts.







    Oil-field-brine injection wells  are discussed in a later



section.
                            36

-------
Alabama
California
Colorado
Florida
Illinois
Indiana
Iowa
Kansas
Kentucky
Louisiana
Michigan

5
4
2
5
5
12
1
27
3
40
27

Nevada
New Mexico
New York
North Carolina
Ohio
Oklahoma
Pennsylvania
Texas
Tennessee
West Virginia
Wyoming

1
1
4
1
8
9
8
71
4
7
1
246
Table 1   Distribution of existing industrial
          wastewater injection wells among the
          22 states having such wells in 1972
          (Warner, 1972) .
Industry Type
Refineries and natural gas
plants
Chemical, petrochemical &
pharmaceutical companies
Metal product companies
Other
Percent of Wells
1967
22
50
7
21
1972
26
56
7
11
Table 2   Distribution of injection wells by
          industry type  (Warner, 1972) .
                   37

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  Initial failure (never operated)

  Operation pending

  Presently operating

  Operation rare or suspended

  Abandoned and plugged (after operating)
 5%

13%

66%

11%

 5%
Table 3   Operational status of  industrial
           injection wells  (Warner,  1972) .
Total Well Depth
(meters)
0 - 300m
300 - 600
600 - 1,200
1,200 - 1,800
1,800 - 3,700
Over 3, 700
Percent of Wells
1967
7
29
22
31
9
2
1972
8
16
29
34
12
1
Table 4    Total depth of industrial injection
            wells  (Warner, 1972)
                      38

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Injection Rate
(liters per second)
0 - 3 Ips
3-6
6-13
13 - 25
25 - 50
Over 50
Percent of Wells
1967
27
17
25
26
4
1
1972
36
13
20
17
7
7
Table 5   Rate of injection in industrial
          wells  (Warner, 1972) .
Injection Pressure
(kilograms per square
centimeter )
Gravity flow
Gravity — 1 0 ksc
10 - 20
20 - 40
40 - 100
Over 100

Percent of Wells
1967
14
29
27
9
20
1
1972
27
22
14
16
18
3
Table 6   Pressure at which waste is injected
          in industrial wells  (Warner, 1972).
                   39

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Rock Type
Sand
Sandstone
Limestone and Dolomite
Other
Percent of Wells
1967
30
45
22
3
1972
36
25
35
4
Table 7   Type of rock used for injection by
          industrial wells (Warner, 1972).
Quaternary 3%
Tertiary 33%
Mesozoic 6%
Permian — Mississippian 15%
Devonian — Silurian 15%
Ordovician — Cambrian 27%

57%

Precambrian 1 %
Table 8   Age of injection zone of  industrial
          wells  (Warner,  1972) .
                    40

-------
    •    Only about 3 percent of existing wells are



         injecting at well-head pressures exceeding 100



         kg/cm2.   This information, in conjunction with the



         range of depths of wells previously mentioned, is



         reassuring; it suggests that presently-operating



         wells are generally using pressures compatible with



         well depth and that waste waters are generally



         being injected into naturally-occurring porosity,



         rather than into continuously induced fractures.







Tables 7 and 8 can be interpreted to show the distribution



of wells by geologic provinces.  The 36 percent of wells



injecting into poorly consolidated sands of Quaternary and



Tertiary age are principally located in the Gulf coastal



Plain.  The 57 percent of wells injecting into consolidated



sandstones and limestones of Paleozoic age are located in



certain interior geologic provinces.  Further examination of



other well characteristics shows that there is a good



correlation between the geologic province, depth,



construction method, and performance of existing wells,



which will permit emphasis on selected locations, aquifers,



and construction and operating requirements in a national



monitoring program.
                            41

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Environmental consequences
 - -•--"" '  — - -~ '""•^"^••^•^Y"™"" l  r LL i pi i|  i« i  ii
Tangible impacts of waste injection that can be predicted to
occur in every case are:

    •    Modification of the ground water system.

    •    Introduction into the subsurface of fluids with a
         chemical composition different from that of the
         natural fluids.

Tangible impacts that could occur in individual cases  are:

    •    Degradation of ground water quality.

    •    Contamination of other subsurface  resources,  such
         as petroleum, coal, or chemical brines.

    •    Stimulation of earthquakes,

    •    Chemical reaction between waste water and natural
         water.
                            42

-------
    •    Chemical reaction between waste water and rocks in



         the injection interval.







The degree to which any of these impacts can be predicted



and quantified in advance depends on the individual



situation.  In the case of existing permitted wells,



significant adverse environmental effects should not occur.



Unfortunately some permitted wells are known to exist that:







    •    Do not have standby facilities.



    •    Have fractured the receiving rocks.



    •    Are injecting into fresh water aquifers.



    •    Have other deficiencies.
Contamination of Fresh Ground Water



The impact of greatest concern to most regulatory agencies



is the contamination of potable ground water.  This could



occur where a well injects into a saline-water aquifer by:







    •    Escape of waste water through the well bore into an



         aquifer containing usable water because of



         insufficient casing or failure of the injection
                            43

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         well casing due to corrosion,  excessive injection



         pressure, etc.







    •    Vertical escape of injected waste water,  outside of



         the well casing, from the injection zone into a



         useable aquifer.







    •    Vertical escape of injected waste water from the



         injection zone through confining beds that are



         inadequate because of high primary permeability,



         solution channels, joints, faults, or induced



         fractures,







    •    Vertical escape of injected waste water from the



         injection zone through nearby wells that are



         improperly cemented or plugged, or that have



         insufficient or leaky casing.







Direct contamination of fresh ground water could also occur



by lateral travel of injected waste water from a region of



saline water to a region of fresh water in the same aquifer.
                            44

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Indirect contamination of fresh ground water can also occur



when injected waste water displaces saline formation water,



causing it to flow into a fresh water aquifer.  Vertical



flow of the saline water could be through paths of natural



or induced permeability in confining beds or through other



inadequately cased or plugged wells.  If large volumes  of



waste water were injected near a fresh-water/saline-water



interface, such as occurs in many coastal aquifers and



inland locations, the interface could be displaced with



saljlne water replacing fresh water in the zone of



displacement.  Ferris (1972)  discusses this response of



hydrologic systems to waste injection.







In many existing injection wells, the potential for direct



contamination of fresh ground water appears to be small



because of the construction used in these wells and because



of the large vertical distance between the injection zones



arid fresh water aquifers.  The belief that the potential for



direct aquifer contamination is small, based on the few



instances of direct contamination that have been documented,



is suspect however and ground water quality near such wells



should be monitored carefully.  The vertical or lateral



movement of saline water into fresh water aquifers as a
                             45

-------
result of increased formation pressures can be expected to



occur.








Contamination of Other Subsurface Resources



No instance of contamination of other subsurface resources



by injected industrial waste water has yet been reported.



The fact that little evidence of degradation of potable



ground water and other resources by this type of injected



waste water has been found may be due to the limited amount



of monitoring being done and should not be cause for



relaxation of vigilance in regulating and operating such



wells.  On the contrary, as more wells are constructed each



year, regulation and operation must be increasingly more



sophisticated to maintain this record.








Chemical reaction between waste water and formation minerals



and water is a possible problem in well operations, but does



not present much potential for environmental impact that



would be of concern to the public.








Earthquake Stimulation



The exact geologic and hydrologic circumstances in which



earthquakes can be stimulated by waste-water injection are
                            46

-------
not yet known.  The general requirement is the presence of a



fault system along which movement can be induced in an area



where earth strains are present that can be relieved by such



movement.  It is believed that fluid injection can act as a



trigger for release of such strain energy, thus causing



earthquakes.  A survey of presently existing industrial



injection wells ether than those injecting oil-field brine



has shown that very few are present in such locations, and



none, besides the Rocky Mountain Arsenal well near Denver,



has yet been related to earthquake occurrence.







Control Methods







The following list describes processes, procedures, and



methods for control of industrial waste water injection into



aquifers.  Control is based on proper siting, design,



construction, operation, abandonment, and monitoring as



briefly discussed in subsequent subsections.







    •    Evaluation of hydrogeologic framework and



         restriction on unsuitable locations and aquifers



         for waste water injection.
                            47

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Evaluation of fluids for injection including

estimation of nature and extent of chemical

reactions between injected fluids and aquifer

fluids and minerals, of heat generation and its

effects in the case of radioactive wastes and

restrictions on those deemed unsuitable.
                       i

Requirement of proper design and construction of

injection wells including hardware and sealants.


Requirement of thorough hydrogeologic evaluation

during construction and testing of wells.


Determination of aquifer characteristics and

estimation of aquifer response to injection, and

direction and rate of movement of injected fluid

and aquifer fluids.


Restriction on operating programs for injection

wells.


Surface equipment and programs for emergency

procedures in the event of malfunction, including
                   48

-------
     rapid shutoff and standby facilities and programs



     for long-term decontamination.







•    Abandonment procedures for all  wells.







•    Monitoring programs for injection wells.








•    Monitoring programs for aquifers.
                        49

-------
     EXTENSIVb AREAS WHERE RELATIVELY
     IMPERMEABLE IGNEOUS-INTRUSIVE AND
     METAMORPHIC ROCKS ARE EXPOSED AT SURFACE

     EXTENSIVE AREAS WHERE V01CANIC SEQUENCES
     ARE EXPOSED AT SURFACE
_—  BOUNDARIES OF GEOLOGIC FEATURES

DfcNVER \ APPROXIMATE BASIN OUTUNF.S
      INDUSTRIAL-WASTE INJECTION SYSTEMS
      (FEBRUARY, 1966)
      GEOLOGIC DETAIL NOT SHOWN
     Figure A  Geologic  features significant in deep waste-
                  injection  well-site  evaluation,  and locations
                  of  industrial-waste  injection systems (Warner,
                  1968) .
                                     50

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Local Site Evaluation



An outline of the factors for consideration in the



evaluation of injection-well sites is given in Table 9.







Experience has shown that nearly all types of rocks can,



under favorable circumstances, have sufficient porosity and



permeability to yield or accept large quantities of fluids.



Sedimentary rocks, especially those deposited in a marine



environment, are most likely to have the geologic



characteristics suitable for waste-injection wells.  These



characteristics are: (1) an injection zone with sufficient



permeability, porosity, thickness, and areal extent to act



as a liquid-storage reservoir at safe injection pressures;



and  (2)  an injection zone that is vertically below the level



of fresh water circulation and is confined vertically by



rocks that are, for practical purposes, impermeable to waste



liquids.
                            51

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 Regional Geologic and Hydrologic Framework
          Structural geology
          Stratigraphic geology
          Groundwater geology
          Mineral resources
          Seismicity
          Hydrodynamics
 Local Geology and Geohydrology
       •  Structural geology
       •  Geologic description of sedimentary rock units
          1. Lithology
          2. Detailed description of potential injection horizons and
            confining beds
            a. Thickness and vertical and lateral distribution
            b. Porosity (type  and distribution as well as amount)
            c. Permeability (same as b)
            d. Chemical characteristics of reservoir fluids
          3. Groundwater aquifers at the site and in the vicinity
            a. Thickness
            b. General character
            c. Amount of use and potential for use
          4. Mineral resources and their occurrence at the  well site
            and in the immediate area
            a. Oil and gas (including past, present and possible
              future development)
            b. Coal (as in a)
            c. Brines (as in a)
            d. Other (as in a)
Table  9    Factors  for consideration  in  the
             geologic and  hydrologic  evaluation  of  a
             sit.e  for deep well industrial waste
             injection.
                          52

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Vertical confinement of injected wastes is important not
only for the protection of usable water resources, but also
for the protection of developed and undeveloped deposits of
hydrocarbons and other minerals.  The effect of lateral
movement of waste on such natural resources also must be
considered.
Unfractured beds of shale, clay, slate, anhydrite, gypsum,
marl, and bentonite have been found to provide good seals
against the upward flow of fluids.  Limestone and dolomite
may be satisfactory confining strata but these rocks
commonly contain fractures or solution channels and their
adequacy must be determined carefully in each case.
The minimum salinity of natural water in the injection zone
probably will be specified by regulatory agencies in most
states, but will be at least 1,000 mg of dissolved solids
per liter of water except under unusual circumstances.
Water containing less than 500 mg/1 is considered to be
acceptable for pctable water used by interstate carriers.
Formerly, if such water was not available, water containing
                            53

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1,000 mg/1 of dissolved solids was considered acceptable.



The minimum salinity in arid regions may be set at a level



higher than 30,000 mg/1 of dissolved solids to provide a



margin of safety and because water with this dissolved-



solids content is used in certain areas to supply



desalination plants which produce fresh water.








Illinois agencies have determined that ground water with a



dissolved solids content less than 10,000 mg/1 should be



protected.  All ground waters in New York have been



classified, based on quality.  According to the New York



classification, waste injection is prohibited in aquifers



containing water with a dissolved solids content of 2,000



mg/1 or less.








It has been found that a confining stratum only a meter



thick may provide a good seal to retain oil and gas.  Such



thin confining beds generally would not be satisfactory for



containing injected waste because they would be very



susceptible to hydraulic fracturing, and even a small fault



could completely offset them vertically.  Fortunately, in



many places hundreds or thousands of feet of impermeable
                            54

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strata enclose potential injection zones and virtually



ensure their segregation.
In addition to stratigraphy, structure, and rock properties,



which are factors routinely considered in subsurface



studies, aquifer hydrodynamics may be significant in the



evaluation of waste-injection well sites.  The presence of a



natural hydrodynamic gradient in the injection zone will



cause the injected waste to be distributed asymmetrically



about the well bcre and transported through the aquifer even



after injection has ceased.








Hydrodynamic dispersion (the mixing of displacing and



displaced fluids during movement through porous media) may



cause much wider distribution of waste in the injection zone



than otherwise wculd be anticipated.  Dispersion is known to



occur in essentially homogeneous isotropic sandstone, and it



could lead to particularly rapid lateral distribution of



waste in heterogeneous sandstone and fractured or cavernous



strata.  Sorption of waste constituents by aquifer minerals



retards the spread of waste from the injection site.
                            55

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Mathematical models now available are satisfactory for



accurately predicting the movement of waste in most natural



aquifers only under restricted, simplified physical



circumstances.  Even if knowledge of the physics of fluid



movement- in natural aquifers were considerably more



advanced,  the determination of the physical parameters that



characterized an injection zone would still be a problem if



few subsurface data were available.  These restrictions do



not, however, preclude the quantitative estimation of the



rate and direction of movement of injected waste.







The maximum pressure at which liquids can be injected



without causing hydraulic fracturing may be the factor



limiting the discharge rate and operating life of an



injection well.  The injection pressure at which hydraulic



fracturing will occur is related directly to the magnitude



of regional rock stress and the natural strength of the



injection zone  (Hubbert and Willis, 1957).  In some areas,



the pressure at which hydraulic fracturing will occur can be



estimated before drilling on the basis of experience in



nearby oil fields.
                            56

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Other considerations in the determination of site



suitability are: (1) the presence of abnormally high natural



fluid pressure and temperature in the potential injection



zone that may make injection difficult or uneconomical;  (2)



the local incidence of earthquakes that can cause movement



along faults and damage to the subsurface well facilities;



(3) the presence in the area of other wells, or, improperly



plugged wells that penetrate the injection zone and provide



a means for escape of injected waste to ground water



aquifers or to the surface; (4) the mineralogy of the



injection zone and chemistry of the resident water, which



may determine the injectability of a specific waste; and  (5)



the possibility that in tectonically unstable areas, fluid



injection may contribute to the occurrence of earthquakes.
Waste Evaluation



A foremost consideration in evaluating the feasibility of



waste injection is the character of the waste.  Table 10



lists some pertinent factors.
                            57

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The  suitability of  waste  for subsurface  injection depends on

its  volume  and physical and chemical properties of the

potential injection zones and their interstitial fluids.
                            •   Volume
                            •   Physical Characteristics
                                1. Specific gravity
                                2. Temperature
                                3. Suspended solids content
                                4. Gas content
                            •   Chemical Characteristics
                                1. Chemical constituents
                                2. pH
                                3. Chemical stability
                                4. Reactivity
                                  a. with system components
                                  b. with formation waters
                                  c. with formation minerals
                                5. Toxicity
                            •   Biological Characteristics
          Table 10  Factors to  be considered  in evaluating
                      the  suitability of  untreated industrial
                      wastes for  well injection.
                                58

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Waste disposal intc subsurface aquifers ordinarily



constitutes the use of limited storage space, and only



concentrated, very objectionable, relatively untreatable



waste should be considered for injection.  The fluids



injected into deep aquifers do not occupy empty pores; each



liter of waste will displace or compress a liter of the



fluid which saturates the aquifer.  Optimal use of



underground storage space will be realized by use of well



injection only where  (1)  more satisfactory alternative



methods of waste treatment and disposal are not available,



and (2)  minimization of injected-waste volumes is achieved



through good waste management.
Knowledge of the mineralogy of the aquifer and the chemistry



of interstitial fluids and waste should indicate the



reactions to be anticipated during injection.  Laboratory



tests can be performed with rock cores and formation and



waste water samples to confirm anticipated reactions.







Selm and Hulse  (1959)  lists the reactions between injected



and interstitial fluids that can cause the formation of



plugging precipitates—(1)  precipitation of alkaline earth
                            59

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metals such as calcium, barium, strontium, and magnesium as



relatively insoluble carbonates, sulfates, orthophosphates,



fluorides and hydroxides; (2)  precipitation of metals such



as iron, aluminum, cadmium,  zinc, manganese, and chromium as



insoluble carbonates, bicarbonates, hydroxides,



orthophosphates, and sulfides; and  (3) precipitation of



oxidation-reduction reaction products.
Common minerals that react significantly with wastes are the



acid soluble  carbonate minerals and the clay minerals.



Acidizing of reservoirs containing carbonate minerals is an



effective well-stimulation technique, and reaction of acidic



wastes with carbonate minerals thus might be expected to be



beneficial.  An undesirable effect of the reaction of acid



waste with carbonate minerals could be evolution of CCU



that might increase pressure and cause plugging if present



in excess of its solubility.  Roedder (1959) reported that



the reaction of acid aluminum nitrate waste with calcium



carbonate results in a gelatinous precipitate that could



cause plugging.
                            60

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Clay minerals are known to reduce the permeability of



sandstone to water in comparison to its permeability to air.



The permeability of a clay-bearing sandstone to water



decreases with decreasing water salinity, decreasing the



valence of the cations in solution, and increasing the pH of



the water.








Ostroff (1965)  and Earner (1965, 1966) give additional



references and discussion concerning waste injectability.



Factors that bear on waste injectability, such as aquifer



mineralogy, temperature and pressure, and chemical quality



of aquifer fluids, are a logical part of feasibility reports



because the treatment necessary to make a waste injectable



can be an important part of a total waste management




program.








Well Construction and^Evaluation



The variability cf geologic situations and the



characteristics of wastes precludes establishment of rigid



specifications for injection-well construction.  Each



injection system requires individual consideration with



respect to 'waste volume and type, and the geologic and
                            61

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hydrologic conditions that exist.  Certain general



requirements, however, can be outlined.








Construction of well facilities for an injection system



includes drilling, logging and testing,  and completion



activities.  A hcle must first be drilled, logged, and



tested before it can be ascertained that it should be



completed as an injection well.  The completion phase



includes installation and cementing of the casing,



installation of injection tubing, and other related



procedures such as perforating or slotting the casing and



stimulating the injection horizon.








Drilling programs should be designed to permit installation



of the necessary casing strings with sufficient space around



the casing for an adequate amount of cement.  Samples of the



rock formations penetrated should be obtained during



drilling.  It may be necessary to have formation cores or



water samples at horizons of particular importance to



provide necessary geologic and hydrologic data.  Logging and



testing data should be filed with the appropriate state



agency or agencies.
                            62

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Table 11 summarizes the type of information desired in



subsurface evaluation of the disposal horizon and the



methods for obtaining this information.








Design of a casing program depends primarily on well depth,



character of the reck sequence, fluid pressures, type of



well completion, and the corrosiveness of the fluids that



will contact the casing.  Where fresh ground water supplies



are present, a casing string (surface casing)  is usually



installed to below the depth of the deepest ground water



aguifer immediately after drilling through the aquifer



(Figure B).  One or more smaller-diameter casing strings are



then set, with the bottom of the last string just above,



into or through the injection horizon, depending on whether



the well is to be completed as an open hole or is to be



cased and perforated.








The annulus between the hole wall and the casing is filled



with cement to protect the casing from external corrosion,



to increase casing strength, to prevent mixing of the waters



contained in the aquifers behind the casing, and to



forestall travel of the injected waste into aquifers other



than the disposal horizon.  Neat Portland cement (no sand or
                            63

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gravel)  is the basic material for cementing.  Many additives

have been developed to impart some particular quality to the

cement.   Additives can, for example, be selected to give

increased resistance to acid, sulfates, pressure,

temperature and shrinkage.
Information Desired
Porosity
Permeability
Fluid pressures in formations
Water samples
Geologic formations intersected
by hole
Thickness and character of
disposal horizon
Mineral content of formation
Temperature of formation
Amount of flow into various
horizons
Methods Available
for Evaluation
Cores, electric logs, radio-
active logs, sonic logs
Cores, pumping or injection
tests, electric logs
Drill stem tests, water level
measurements
Cores, drill stem tests
Drill time logs, drilling samples,
cores, electric logs,
radioactive logs, caliper logs
Same as above
Drilling samples, cores
Temperature log
Injectivity profile
         Table 11  Summary of information desired in
                   subsurface evaluation of disposal
                   horizon and methods available for
                   evaluation.
                             64

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Temperature logs, cement logs, and other well-logging



techniques can be required as a verification of the adequacy



of the cementing.  Cement can be pressure-tested if the



adequacy of a seal is in question.








Waste should be injected through separate interior tubing



rather than being in contact with the well casing.  This is



particularly important when corrosive wastes are being



injected.  The injection tubing can be made from, or lined



with, a material that is not affected by the particular



waste involved.  A packer can be set near the bottom of the



tubing to prevent corrosive waste from contacting the



casing.  Additional corrosion protection can be provided by



filling the annular space between the casing and the tubing




with oil or water containing an added corrosion inhibitor.
                            65

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                                               Tubing Pressure Gauge
Fresh-Water-Bearing
Surface Sands And
Gravels
Impermeable Shale

Confined Fresh-Water
Bearing Sandstone
Impermeable
Shale

#
O1 • . 0 ' •
-^ *.'••>.'•••
oXvv*.
~ ~ -
•'•'•.': -• •'.-' •'•'.'
*• ~-_-' T— ._~"

^
1
^
1
^
X \
^
/^
'S
/ V
^
i s
0 \
<&
   Annulus Pressure Gauge
Permeable Salt-Water
Bearing Sandstone
Injection Horizon
-; •',- Surface Casing Seated In
 ~Z. Impermeable Formation
   Below Fresh Water And
   Cemented To Surface

   Inner Casing Seated In
   Injection Horizon
   And Cemented To Surface
   Injection Tubing
  : Annulus Filled With
   , Noncorrosive Fluid
- ^ Packers To Prevent Fluid
   Circulation In Annulus

 ' . Open-Hole Completion
Impermeable Shale
 Figure B   Schematic  diagram  of an industrial  waste
              injection  well  completed in sandstone
              (modified  after Warner,  1965).
                                66

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It is frequently desired to increase the acceptance rate of



injection wells by chemical or mechanical treatment of the



injection zone.  Careful attention should be given to



stimulation techniques such as hydraulic fracturing,



perforating, and acidizing to insure that only the desired



intervals are treated and that no damage to the casing,



cement, or confining beds occurs.








Aquifer Response and Wastewater Movement



Estimates of the rate of pressure build-up in the injection



zone are important because the maximum pressure at which



liquids can be injected may be the factor limiting the safe



injection rate and operating life of an injection well.



Excessive pressure may cause the rupturing of the injection



formation and the movement of the waste to fresh water



aquifers.








From data obtained during construction and testing of an



injection well, estimates can be made of the rate of



increase of pressure in the receiving aquifer for a



projected rate of waste water injection.  Van Everdingen



(1968)  outlines the methodology for estimating the pressure



build-up resulting from injection wells.
                            67

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Estimates of the lateral extent of waste water movement are



needed so that the location of the underground space



occupied by the waste water can be made a matter of record



to be used in regulation and management of the subsurface.








Estimates of the extent and direction of waste water



movement can be made after the hydrogeologic characteristics



of the receiving aquifer have been determined.  This



estimate is potentially very complex, since the cylindrical



pattern that can be assumed as the most elementary case may



be modified by the natural flow system in the aquifer,



hydrodynamic dispersion, differential permeability in the



injection zone and density and viscosity differences between



injected and interstitial fluids.








Operating Program



The operating program for an injection system should conform



with the geological and engineering properties of the



injection horizon and the volume and chemistry of the waste



fluids.








Injection rates and pressures must be considered jointly,



since the pressure will usually depend on the volume being
                            68

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injected.  Pressures are limited to those values that will



prevent damage to well facilities or to the confining



formations.  The maximum bottom-hole injection pressure is



commonly specified on the basis of well depth.  Regulatory



agencies have specified maximum allowable bottom-hole



pressure of from about 0.11 to 0.23 kilograms per square



centimeter per meter of well depth, depending on geologic



conditions, but operating pressures are seldom allowed to



exceed about 0.18 ksc per meter of depth.







Experience with injection systems has shown that an



operating schedule involving rapid or extreme variations in



injection rates, pressures, or waste quality can damage the



facilities.  Consequently, provisions should be made for



shut-off in the event of hazardous flow rates, pressure, or



waste quality fluctuations.







Surface Equipment and Emergency Procedures



Surface equipment includes holding tanks and flow lines,



filters, other treatment equipment, pumps, monitoring



devices, and standby facilities.
                           69

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Surface equipment associated with an injection well should



be compatible with the waste volume and physical and



chemical properties to insure that the system will operate



as efficiently and continuously as possible.  Experience



with injection systems has revealed the difficulties that



may be encountered due to improperly selected filtration



equipment and corrosion of injection pumps.







Surface equipment should include well-head pressure and



volume monitoring equipment, preferably of the continuous



recording type.  Where injection tubing is used, it is



advantageous to monitor the pressure of both the fluid in



the tubing and in the annulus between the tubing and the



casing.  An automatic alarm system should signal the failure



of any important component of the injection system.  Filters



should be equipped to indicate immediately the production of



an effluent with too great an amount of suspended solids.







Standby facilities are essential in order to cope with



malfunctions of a well that might occur.  In all cases,



provision should be made for alternative waste management



facilities and procedures in the event of injection system
                            70

-------
failure.  Alternative facilities could be standby wells or



holding tanks.








In situations where the character of the waste water being



injected would dictate the need, additional facilities and



procedures could be available for use in the event of



engineering failures of the system or detection of



contamination of a subsurface resource.  For example,



handling of a particularly corrosive waste water would be



reason for planning in advance the procedure to be used in



the event that tubing failure during operation was detected.



Such a procedure might be to begin immediately injection of



a non-*corrosive liquid into the well until the well bore was



completely cleared, then to shut the well in until the



reservoir pressure had declined to a level that would allow



removel of the damaged tubing without backflow of the



corrosive waste water.  Such a procedure would help to



minimize damage to the casing, packer, etc.  Injection of a



radioactive waste water would require establishment of



procedures for use during well workovers or any other



handling of equipment that might become contaminated.
                           71

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Emergency procedures could also include notification of



nearby users of ground water or other resources, should



contamination be detected, or even a program for aquifer



rehabilitation.







Monitoring Procedures



Monitoring can be performed on the injection system itself,



in the injection zcne, or in aquifers above or below the



injection zone.







Well-head pressure and waste injection rate should be



continuously measured.  If injection tubing is used, the



casing-tubing annulus should be pressure monitored.  Other



types of monitoring include measurement of the physical,



chemical, and biological character of injected fluids on a



periodic or continuous basis, and periodic checking of the



casing and tubing for corrosion, scaling, or other defects.







The possible purposes in monitoring the injection zone or



adjacent aquifers are to determine fluid pressures and the



rate and direction of movement of the waste water and



aquifer fluids.
                            72

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As discussed by Viarner  (1965) , monitoring with wells to



determine the rate and extent of movement of waste water



within the injection zone may be of limited value because of



the difficulty of intercepting the waste water front and of



interpreting information that is obtained.  For these



reasons, and because of the cost, few such monitor wells



have been constructed.








A more feasible approach is to monitor the fluid pressure in



the injection zone or adjacent aquifers.  A larger number of



monitor wells have been constructed for this purpose.



Goolsby (1971)  discusses an example of an injection system



where a monitor well was useful for both detection of waste



travel and measurement of reservoir fluid pressure.








The most common type of monitor well used in conjunction



with waste water injection systems is that constructed in



the fresh water aquifers near the injection well.  If these



wells are pumping wells, they provide a means for detecting



(eventually)  leakage from the injection well or injection



horizon; pollutants entering the supply aquifer will tend to



move toward a discharging well.  Changes in the quality of



water in springs, water supply wells, streams and lakes may
                            73

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also be monitored to detect effects from waste disposal
wells.


Sta te_Programs
The status of regulation of disposal wells at the state
level is highly variable.  Most states that have significant
oil production regulate the disposal of oil field brine
through an oil and gas agency, but other categories of
disposal wells are most frequently regulated through water
pollution control, environmental protection, or health
agencies.

  /
A few states have developed specific laws, regulations, or

policies concerning industrial waste water injection.  A
chronological list of these developments is given below:
    1961      Texas - Injection well law adopted
    1966      Kansas - Regulations adopted
    1967      Ohio - Injection well law adopted
              New York - Ground water classified
    1969      Indiana - "Test Hole" Legislation enacted

              Michigan - "Mineral Well Law" enacted
              New York - Injection well policy established
              Ohio Valley - Regulatory policy recommended
                            74

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              Texas - 1961 law amended



              West Virginia - Injection well legislation



                              enacted



    1970      Illinois - Policy specified



              FWPCA - Policy announced



              Colorado - Rules and regulations for



                         subsurface disposal adopted



    1971      Missouri - Disposal wells prohibited



    1972      Oklahoma - Regulations adopted



              Council of State Governments - Model



                        State Toxic Waste Disposal Act



    1973      EPA - Policy announced.







Texas was the first state to pass a law specifically



concerning industrial, waste water injection wells, in 1961.



Since that time, several other states have passed similar



laws or amended existing ones to include consideration of



underground injection.  Formal regulations have been adopted



by Colorado and Oklahoma.  Formal or informal policy



guidelines have fceen specified by several states.  with the



exception of the specific cases listed above, most states



regulate injection wells under general water pollution



control laws, oil and gas laws, or both.  There is
                            75

-------
frequently overlapping jurisdiction among state agencies



regarding such wells.








Because regulation of industrial waste water injection wells



is a relatively new responsibility, the laws, regulations,



and policies in this area are in the developmental stage.



During 1970-1972, an advisory committee to the Ohio River



Valley Water Sanitation Commission (ORSANCO)  formulated



policies, procedures, and technical criteria for use by the



eight member states  (Illinois, Indiana, Kentucky, New York



Ohio, Pennsylvania, Virginia, and West Virginia).  In



January 1973, ORSANCO formally adopted the committee



recommendations as Resolution 1-73, incorporating eight



steps:








    1.   Preliminary assessment by the applicant of the



         geology and hydrogeology at the proposed well site



         and the suitability of the waste water for



         injection.  These initial studies should be made in



         consultation with the appropriate state agencies.








    2.   Application to the state agency with legal



         jurisdiction for permission to drill and test a
                             76

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     well for subsurface waste water injection.   The



     application must be supported by a report that



     documents all details of the proposed injection



     system, including monitoring and emergency standby



     facilities.  On issuance of a permit, the applicant



     will be apprised of the geologic and geohydrologic



     parameters that will be employed by the state in



     reaching its final determination on feasibility of



     waste water injection into the well, anticipated



     limitations on injection pressure and injected



     volumes, the probable monitoring requirements, and



     probable requirements for alternative waste water



     management programs in the event that operational



     problems occur during the use of the injection



     well.







3.    Drilling and evaluation of the well and submission



     of samples, logs, test information, and a well-



     completion report to the state.







4.    Request by the applicant for approval to inject



     waste water into the well.  The request should
                        77

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     indicate any changes from the original plan in



     system construction and operating program.








5.    Prompt evaluation, by the State, of the well and



     approval, approval-witb-modification, or



     disapproval of the proposed injection system based



     on the geologic,  geohydrologic, and engineering



     data submitted.  On approval, the applicant will be



     provided with specific instructions and monitoring



     requirements.








6.    Operation of the injection system in accordance



     with State requirements.  The appropriate



     regulatory agency should be notified immediately if



     operational problems occur, if remedial work is



     required, or if significant changes in the waste



     water stream are anticipated.








7.    Abandonment of the well in accordance with state




     regulations or other technically acceptable




     procedures.
                        78

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    8.    In addition to the seven steps listed above, where



         a proposed injection well is to be located within



         five miles of the state border, the appropriate



         agencies in the adjacent state should be provided



         the opportunity to review and comment on the



         application.  Further, these agencies should be



         advised of any significant problems that occur



         during the operation of such a well.








These procedures are supplemented by forms, outlines, and



technical criteria to be used in implementation.  It is



anticipated that the individual states will formally or



informally adopt the procedures and supplementary material,



with such modifications as each may wish to make to meet



state organizational and administrative needs.  It is



intended that the recommendations will be updated and



modified as experience shows it to be necessary.








An example of the application of ORSANCO Resolution l-*73 to



a particular state is provided by Warner (1972) in a report



to the Illinois Institute for Environmental Quality.
                            79

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OTHER WELLS







In addition to the types of industrial waste water injection



wells discussed above, other classes of wells are possible



sources of ground water contamination.  Such wells include



those used in conjunction with oil exploration and



production, solution mining, geothermal energy production,



sewage treatment, desalination, radioactive waste disposal,



underground gas storage and water exploration and



production.







Many of the technical and regulatory aspects that have



previously been described apply to these wells.  The



differences that exist will be discussed.







Petroleum Industry Wells



Wells are used by the petroleum industry for exploration,



for production of cil and gas, and for injection of brines



brought to the surface during oil production.  The purpose



of brine injection may be to maintain reservoir pressure, to



provide a displacing agent in secondary recovery of oil, or



to dispose of the brine.
                            80

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The total number of petroleum exploration and production



wells that have been drilled in the United States since the



first oil well was constructed in 1859 is unknown, but the



number exceeds 2,300,000.  Iglehart  (1972) reported, in the



American Associaticn of Petroleum Geologists i&th. An.n_uai



B§port on DrilljLng Activity in the United States, that



27,300 wells were drilled in 1971, a year in which drilling



activity was at a low level.  The number of existing brine



injection wells is not documented either, but inquiry among



the oil producing states indicated that in 1965 about 20,000



such wells existed in Texas alone (Warner, 1965}, with



probably an equal number distributed among all other states.



Information gathered by the Interstate Oil Compact



Commission (1964)  shows that about 1.4 billion metric tons



of water were produced in 1963 in conjunction with



petroleum.  At that time, about 72 percent of the produced



water was reinjected.  The relative percent being reinjected



today is undoubtedly higher as other means of disposal, such



as in unlined pits, have since been outlawed in Texas and



other states.








Hazard to usable ground water may result from any well,



including petroleum production wells, that is inadequately

-------
cased, cemented, or plugged.  Such wells provide avenues for



interaquifer movement of saline ground water and other



fluids.  A particular danger to usable ground water is posed



by the hundreds of thousands of oil and gas wells that were



drilled in the late 1800's and early 1900's and abandoned



with inadequate plugging.  Examples of ground water



contamination caused by abandoned, improperly-plugged oil



and gas wells could probably be found in most petroleum-



producing states.  Fryberger  (1972), Wilmoth  (1971), and



Thompson  (1972)  discuss cases from Arkansas, West Virginia,



and Pennsylvania, respectively.







The mechanism of possible ground water contamination from



oil field brine injection wells is essentially the same as



was discussed for other industrial waste water injection



wells.  Since oil field brine is a natural water and does



not usually contain chemicals that are extremely toxic in



small quantities, it may be of less concern as a pollutant



from a public health standpoint than some other industrial



waste waters.  However, the very high levels of dissolved



solids that are found in many cases, and the volumes



involved, present the potential for degradation of very



large amounts of usable ground water if brine injection is
                            82

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not properly managed (Ostroff,  1965).  It is commonly



believed that most brine is returned to the same geologic



formation from which it was removed.  The relative amount



returned to the same formation as compared with that



injected into other horizons is not known, but substantial



amounts are injected into aquifers that have not been



depressured by petroleum production.  A particular example



of this is injection of oil field brines into the Glorieta



Sandstone in the Oklahoma Panhandle and adjacent areas



(Irwin and Morton, 1969).  The hazard from this practice is



from interaquifer flow of brine, or alternation of the



position of the fresh-water saline-water interface.








The procedures and methods for control and regulation of



brine injection are essentially the same as discussed for



industrial waste water injection.  Locating and plugging



abandoned oil and gas wells may be difficult and expensive.



Pasini and others (1972) discuss the technology and cost of



plugging abandoned wells in the Appalachian area.  The cost



ranged from $8,600 to $14,000 each for the four wells



plugged in that study.   The average cost for plugging 60



abandoned wells in The Hubbard Creek Reservoir Watershed



during the period 1963-1965 was $1500 each.
                            83

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A detailed investigation of the problems presented by one



incident of pollution of a fresh water aquifer by an oil



field brine was made by Fryberger (1972).  The present



extent of the brine pollution is 2.6 square kilometers (one



square mile); however, it will spread to affect 11.7 sq. km



(4-1/2 square miles) and may persist for more than 250 years



before being flushed from the aquifer if indeed it were ever



completely removed.  Several methods for rehabilitating the



aquifer were examined; costs ranged from $80,000 to



$7,000,000 and no method is economically justified at the



present time.







Wells Used in Sglution Mining



For many years wells have been used to extract sulfur, salt



and other minerals from the subsurface by injection of water



and extraction of the minerals in solution.  In many cases



the residual brine from such operations is disposed of



through injection wells.  A similar type operation, widely



practiced in areas where salt deposits exist, is the



construction of solution caverns for storage of liquid



petroleum gas.  In this procedure water is injected into the



salt beds and a caveru developed as the salt is dissolved
                            84

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and the brine pumped out.  The extracted brine is then



disposed of by injection into a suitable aquifer.








A relatively new practice is the in situ mining of metals,



particularly copper, by the injection (through wells) of



acid into an ore body or a tailings pile, and the extraction



of the solution containing the metal through pumping wells



or as seepage.  In at least one case, a deep injection well



is planned for disposal of the spent acid solution, after



the metals have been removed.








The potential problems of ground water pollution from the



solution mining cf soluble minerals, and the techniques for



prevention of such pollution,  are similar to those described



previously.  Solution mining of metallic minerals presents a



different problem in that the mining will, in most cases, be



in geologic strata containing usable water.  The mining



itself may need to be carefully managed to avoid ground



water contamination.  Disposal of the spent acid solutions



by injection would be similar to other industrial waste



water injection.
                             85

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McKinney (1973)  and Pernichele  (1973) discuss current trends



in solution mining and mining geohydrology and list a number



of recent references.
       mJ;-'- Energy. feell§
The Geothermal Steam Act of 1970  (Public Law 91-581)



provides an important impetus to the further development of



geothermal energy sources.  In the United States, about 0.73



million hectares  (1.8 million acres) are designated as known



geothermal resource areas and an additional 38.7 million



hectares  (95.7 million acres) have prospective value  (USGS,



1971) .  Of the known areas, 90 percent lie in the thirteen



western states and Alaska.  Geothermal reservoirs may



contain either dry steam or hot brines, with the latter



predominating.  Both condensed steam and cooled brines



commonly are reinjected through wells into the geothermal



structure  (US. Department of the Interior, 1971) .







At present, the two most significant geothermal areas in the



United States are The Geysers and Imperial Valley, both in



California.
                            86

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A substantial amount of electrical energy already is



generated from dry steam produced at The Geysers.  A three-



fold increase in capacity is planned by 1975.  Injection



wells are used to return condensate to the reservoir.



Because of oxygen content, the condensate is reported to be



corrosive, necessitating the use of special materials



(Chasteen, 1972) .








The United States Eureau of Reclamation and others have



proposed major developments of geothermal energy from the



hot brine reservoirs underlying the Imperial Valley.  The



Bureau of Reclamation concept contemplates production of



0.31 million hectare-meters (2.5 million acre-feet)  of fresh



water per year.  The 0.37 to 0.49 million hectare-meters (3



to 4 million acre-feet) of brines withdrawn would be



replaced by water from the Pacific Ocean, the Salton Sea, or



other sources.  Replacement water would be injected through



approximately 100 wells on the periphery of the qeothermal



field, to maintain reservoir pressures and preclude land



subsidence and lowering of the overlying fresh water table



(Bureau of Reclamation, 1972).  The high pressures and



temperatures and the corrosiveness of the injected fluid are



a particular problem in such injection wells; plugging a
                            87

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well if subsurface casing damage occurs could be difficult



or even impossible.
                            88

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Wglls_for Injection of Sewage Effluent and Desalination



Plant Brines



A few wells have been constructed in Florida, Hawaii,



Louisiana, and Texas for injection of treated sewage



effluent into salt water aquifers.  It has also been



proposed to inject brines from advanced waste treatment



plants using desalination techniques, and from plants



constructed to produce usable water by desalination methods.








The technology of injecting such waters is similar to that



previously discussed.  The particular problem with this



category of waste waters is the very large volume that may



be produced.  In general the disposal of sewage effluent by



injection into saline aquifers probably is questionable for



at least two reasons: The effluent is of too high a quality



to waste, and the amount that can be safely injected is too



small to be significant in solving the overall problem of



managing such wastes.  Under certain conditions a double



benefit can be realized by injecting a good quality sewage



effluent so as to displace a poor quality ground water, thus



creating a reserve of usable water in underground storage.
                            89

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Injection of brines from desalination plants may be the most



desirable method of disposing of these wastes in cases where



the geology is suitable and the volumes of waste are not too



large (Dow Chemical Company, 1972).








Radioactive Waste_Disposal Wells




The possible use of injection wells for disposal of



radioactive wastes has been the subject of extensive



investigation since the early 1950's.  To date, at least



three wells have been constructed for injection of liquid



radioactive waste waters into deep aquifers, but the only



one that has been used for this purpose is located at a



uranium mill at Grants, New Mexico (Arlin, 1962).  In spite



of the limited use of injection wells in the past, they may



be the most desirable means of handling some radioactive



liquids today and perhaps others in the future  (de Laguna,



1968; Belter, 1972).








Particular problems related to injection of liquid



radioactive waste are the possible extreme toxicity of the




waste and the heat generated by radioactive decay.
                            90

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A second method of radioactive waste disposal through wells



is injection of radioactive wastes incorporated in cement



slurries into hydraulic fractures induced in thick shale



beds.  This method of disposal has been used for



intermediate level wastes at the Oak Ridge National



Laboratory since 1966 and is being tested at the Nuclear



Fuel services Chemical Processing Plant site in West Valley,



New York (Belter, 1972) .  A discussion of the environmental



aspects of this disposal method is provided by de Laguna and



others (1971) .








Gas Storage Wei1s



Underground gas storage may be defined as storage in rock of



synthetic gas or of natural gas not native to the location.



Storage can be in depleted oil or gas reservoirs, in



aquifers, in mined caverns, or in dissolved salt caverns.



Gas may be stored in gaseous or liquid form.








The largest quantities of gas are stored in the gaseous form



in depleted oil or gas reservoirs or in aquifers.  In 1971



there were 333 underground gas storage fields in 26 states.



About 60 percent of the storage capacity was located in



Illinois, Pennsylvania,  Michigan, Ohio, and West Virginia.
                            91

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The number of wells per field ranges from less than 10 to



more that 100, depending on the size of the structure in



which the gas is being stored (American Gas Association,



1967 and 1971).








Underground gas storage fields present a potential for



contamination of usable ground water by leakage of gas



through the confining beds, through abandoned improperly



plugged wells, or through inadequately constructed gas



injection or withdrawal wells.  Gas could also escape from



an overpressured field and migrate laterally in the storage



aquifer, which in some cases contains usable water.  A case



history of a leaky storage field in Illinois was documented



by Hallden (1961).  In that instance, it was not possible to



conclusively determine whether the leakage was from faulty



well cementing, lack of an adequate confining bed, faulting



of the confining bed, or unplugged abandoned wells.  Some



leakage from storage fields is common, but  since the gas is



a valuable commodity, operating companies have a strong



interest in minimizing such losses.  Storage fields are



subject to state or federal licensing and regulation so the



engineering characteristics of a field must be carefully
                            92

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determined prior to licensing, and the fields must be



monitored during operation.








Water Wells



The mere existence of any type of well so poorly construcrx-ri



that surface materials can fall or run down the hole is a



ground water pollution hazard.  Due to the technology



employed, most injection wells and oil wells are not so



poorly constructed.  The main offenders are water wells,



some of which permit the introduction, directly into



aquifers, of dead skunks and the like, and many of which



provide a path fcr polluted surface water and septic tank



effluent to drain directly into the aquifers from which



drinking waters is drawn, at a point very near the intake.








This obvious hazard has an obvious solution in the excerise



of reasonable care, by competent well drillers, in well



construction.  An impermeable material (preferably neat



cement) should be emplaced around the surface casing, from



top to bottom, to prevent downward movement of pollutants.








    Specific water well pollution problems result from:
                            93

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    •     Gravel  packed wells  where the gravel  pack  extends



         from land surface  to the aquifer or extends into an



         aquifer containing mineralized or undesirable



         water.








    •     The pulling of the well casing in a gravel packed



         well that leaves a gravel conduit extending from



         the surface to the aguifer.








    •     Insufficient casing  and improper grouting  of casing



         in water wells in  basalt formations.








    •     Improper location  of perforations.








    •     Improper cr inadequate welding of casing joints.








    •     Leaky pitless adapters.








    •     Leaky well seals.








    These obvious hazards have an obvious solution in the



application of adequate standards for the construction and



abandonment of water wells  by competent well drillers.
                            94

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   ^      and Abandoned^Wells



Most dry holes are not dry.  The term "dry hole" is really



an indicator of the failure of a hole in the ground to



produce a desired fluid in a satisfactory amount, be it



crude oil, natural gas, water or whatever.








As with most other human failures, the tendency is to avoid




throwing good money after bad, to walk away and to forget



it.  Such a philosophy often leaves an improperly plugged



hole that provides a direct and speedy route for the



movement of surface pollutants into good aquifers.  It also



leads to the direct and speedy movement of fluids from



contaminated aquifers to good aquifers, and to the surface.



It should be noted that many states have regulations



governing the plugging of abandoned wells, especially oil



and gas wells.








Control measures are similar to those for successful wells,



that is, the effective sealing by an impermeable substance



of routes of unwanted vertical communication.
                            95

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References

1.   American Gas Association, Inc., Survey  of  Gas  Storage
    Facilities in UnjLted States  and Canadat  New  York "(1967) .

2.   American Gas Association, Inc., The Underground  Storage
    of Gas in the United States^ New York""~(i971) .  ~"

3.   Arlin, Z. E., "Deep-Well Disposal of Urainum  Tailing
    Water," Proceedings _2nd Conference on Ground Disposal of
    EJ^iSfJciriy.^ 5il .§£§.§.£. Chalk River, Canada, U.S.  Atomic
    Energy~Commission THH7628,  Bk. 2, pp 356-360  (1962).

U.   Ballentine, R.K., Reznek, S.R., and Hall,  C.W.,  Subs_urface
    Poiiiiii0!! Problems in the United States^ US.
    Environmental Protection Agency Technical  Studies Report
    TS-00-72-02, Washington, D.C.  (1972).

5.   Belter, W.G., "Deep Disposal Systems for Radioactive
    Wastes," Underground Waste Management and  Environmental
    Implications^ American Association of Petroleum
    Geologists Memoir 18, Tulsa, Oklahama  (1972) .

6.   Bureau of Reclamation, Geothermal Resource
    Investigatipns f Imperial Va^
                 ^
    Developmental Concepts^ US Department  of  the  Interior,
    Boulder CityT Nevada, 58 pp  (1972).

7.  Chasteen, A.J., "Geothermal  Energy - Growth Spurred on
    by 'Powerful Motives'", ^Mining  Engineering^  Society of
    Mining Engineers of AIME, Vol. 24, No7~"lO,  pp 100-102
    (1972) .

8.  Cook. T.D.  (editor), Underground Waste Management and
    Environmental Imp.licati.onsx  American Association of
    Petroleum Geologists Memior,  Tulsa, Oklahoma,  412 pp
    (1972) .

9.  de Laguna, W,, "Importance of Deep Permeable  Disposal
    Formations in Location of a  Large Nuclear-Fuel
    Reprocessing Plant," Disjgosal in Geologic Basins - Stud1
    Qf £§servoir Strata^ American Association of  Petroleum
    Geologists~Memoir  10, pp 21-31  (1968),
                            96

-------
10.  de Laguna, W.r et al. Safety Analysis of Waste Disposal
    by. SY-dr^Jiii0. ZJSStujiiSS 1J= 2^lS S^^Sx <->a'c Ridge National
    Laboratory~*Report 4665, Oak Ridge, Tennessee, pp  1-6
    (1971).

11.  Donaldson, B.C., Subsurface Disposal of Industrial
    Wastes in the United Statejx UjS. Bureau~~of Mines
    Information Circular 82127^34 pp  (1964).

12.  Dow Chemical Company (Freeport, Texas), "Final Disposal
    of Effluent Brines from Inland Desalting Plants,"
    Environment Pollution and Control^ Report OSW-RDPR-72-
    817 (T§72)7

13.  Ferris,  J.G., "Response of Hydrologic Systems to Waste
    Storage," Underground Waste Management and Environmental
    IffiEii£§ti°H5x American Association of Petroleum
    Geologists Memoir 18f Tulsa, Oklahoma, pp 126-130
    (1972) .

14.  Dryberger, J.S., Rehabilitation of a Brine-Polluted
    A3uiferx US. Environmental Protection Agency,      ~*
    Environmental Protection Technology Series EPA^R2-014,
    Washington, C.C., 61 pp (1972).

15.  Galley,  J.E.  (editor). Subsurface Disposal in Geologic
    Basins^ American Association ol Petroleum Geologist
    Memoir 10, TulFi, Oklahama  (1968).

16.  Galley,  J.E., "Geologic Basin Studies as Related to
    Deep-Well Disposal," Proceedings 2nd Conference on
    Ground Disposal of Radioactive Wajstes^ Chalk River,
    Canada,  UjS. Atomic Energy Commission TID-7628, Bk. 2, pp
    347-335 (1962) .

17.  Goolsby, D.A., "Hydrogeochemical Effects of Injecting
    Wastes Into a Limestone Aquifer Near Pensacola,
    Florida," Ground Waterx Vol. 9, No. 1, pp 13-19 (1971) .

18.  Hallden, O.S., "Underground Natural Gas Storage
    (Hers cher Dome) ," Ground Water Cont jm in at ign^ US.
    Department of Health, Education,"and Welfare, R.A. Taft
    Sanitary Engineering Center, Technical Report W61-5,
    Cincinnati, Chio, 218 pp (1961).
                            97

-------
19.  Hubbert,  M.K., and Willis, D.G., "Mechanics of Hydraulic
    Fracturing," Journal of PetroJLeum Technology^ American
    Institute of Mining, Metallurgical Engineers Petroleum
    Division, Trans., T.P. 4597, pp 153-168  (1957).

20.  Iglehart, C.F., "North American Drilling Activity in
    1971," Bulletin^ American Association of Petroleum
    Geologists^. Vol. 56 No.7, pp 7i45-lT74~"(1 974) .

21.  Interstate Oil Compact Commission, Water. Problems
    Associated with Oil Production in the United States,
    Oklahoma, City, Oklahoma, 88 pp (1964)7

22.  Irwin, J.H., and Morton, R.B., Hydrogeologic Information
    on The Glor^ieta Sandstone and the Ogallala Formation in
    the Oklahoma Panhandlfe and Adjoining Area^ as Related to
    Underground Waste Disposalx U.S. Geological Survey
    Circular 630,~26 pp (1969f.

23.  Ives, R.E., and Eddy,  G.E., Subsurface Disposal of
    Industrial Was^tes^ Interstate Oil Compact Commission,
    Oklahoma City, Oklahoma,  109 pp (1968).

24.  Love, J.D., and Hoover, L., A Summary of the Geology of
    Sedimentary Basins of the United Statesx with Reference
    to the Disposal of Rjadioa£tiye~'wasteSjL U.S. Geological  "
    Survey Trace Elements inv.^Report 76^  (open file),  92 pp
    (1960) .

25.  McKinney, W.A., "Solution Mining," Mining Engineering,
    pp 5657,  February  (1973).

26  Ostroff,  A.G., Introduction to Oilfield Water
    Technology,. Prentice-Hall, Inc. , Englewood Cliffs,  New
    Jersey, 412 pp  (1965).

27.  Pasini, J., Ill, et al, "Plugging Abandoned Gas and Oil
    wells," Mining Congress Journal^ pp 37-42, December
    (1972) .                     ~*~""
                            98

-------
28.  Pernichele, A.E., "Geohydrology," Minjirvg Engineering^  pp
    67-68, February  (1973).

29.  Rima, R., et al, Subsurface Waste Disposal by Means of
    Wel^s - A Selective Annotated Bibliog^aghy,  US. Geological
    Survey Water - Supply Paper 2020  (T971).

30.  Roedder, E., Problems in the Disposal of Acid Aluminum
         te High-Level M^i2i£ii^ Waste Solutions Ey
            n Into Deeglying Permeable Formations^ US.
    Geological"Survey Bulletin 1088, 65~"pp  (1959).

31  Selm, R.P., and Hulse, B.T., "Deep-Well Disposal of
    Industrial Wastes," .1.4th Industrial Waste Conference
    Proceedings^ Purdue University Engineering Extension
    Series No. 104 pp 566-586  (1959).

32.  US Department of the Interior, Geothermal Leasing
    Program^ NTIS Accession No. PB 203 10^2-D, Washington,
    D.C.   (1971) .

33.  US. Environmental Protection Agency, Subsurface Water
    Pollution f A Selective Annotated BibliqgraghyJ Part J
    Subsurface WaSte In1ectione office of Water Programs,
    Washington, 5Tc., 156 pp "(1972) .

34.  Van Everdingen, A.F., "Fluid Mechanics of Deep-Well
    Disposals," Subsurface Disposal in Geologic Baains - A
    Study of Re^ejcvoir Strata^ American Association of
    Petroleum Geologists Memoir 10, Tulsa, Oklahoma, pp 32-
    42 (1968) .

35.  Warner, D.L., Deep-We11 Injection of LicQiid Waste^ US.
    Public Health Service Environmental Publication No.
    999-WP-21, 55 pp (1965).

36.  Warner, D.L., "Deep-Well Waste Injection -- Reaction
    with Aquifer Water," Proceedingsx American Society of
    Civil Engineers^ Vol. 92, No SA4, pp 45-69  (1966).

37.  Warner, D.L., Deep.~Wells for Industrj.al Waste Infection
    in the United States - Sununary of Datax FeSeral Water
    Pollution Control Administration,. Water Pollution
    Control Research Service Publication No. WP-20-10, 45  pp
    (1967) .
                             99

-------
38.  Warner, D.L., "Subsurface Disposal of Liquid Industrial
    Wastes by Deep-Well Injection," Subsurface pijsgojsaj. in
    Geologic BasJLns - A Study of. Reservoir Strataf American
    Association of"petroleum Geologists Memoir To, Tulsa,
    Oklahoma, pp 11-20  (1968).

39.  Warner, D.L., Subsurface Industrial Wastewater Injection
    ifi liiinoijx Illinois Institute for Environmental
    Quality Document N. 72-2, 125 pp  (1972).

40.  Warner, D.L., Survey of Jndvis trial Waste Injection
    Wells^ 3 Vols. , Final Report, U.S. Geological Survey
    Contract No. 14-080001-12280, University of Missouri,
    Rolla, Missouri  (1972).

41.  Wilmoth, B.M., "Occurrence of Salty Groundwater and
    Meteoric Flushing of contaminated Aquifers," Proceedings
    of National Grcundwater Quall-ty Synposjum^ EPA Water
    Pollution Control Research Series 16060 GRB 08/71
    (1971).

42.  Young, A., and Galley, J.E.  (editors), Fluids in
    Subsorface Environments^ American Association of
    Petroleum Geologists Memior 4, Tulsa, Oklahoma, 414 pp
    (1965).
                             100

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INJECTION INTO FRESH WATER AQUIFERS



Scope^of the Problem



Although most of the estimated 15 million wells in the



United States are used for the production of fresh water,



many thousands of wells in various parts of the country have



been and are still being used only for the disposal of



pollutants into fresh water aquifers.  This practice has



been followed, fcr example, by the petroleum industry in



some areas for getting rid of brines and by other industries



for disposing of chemical wastes.  Fuhriman and Barton



(1971) ,  referring to ground water pollution in the



southwestern United States, state that "occasionally,



industries or others have used shallow injection wells to



dispose  of liquid wastes," and cite as an example electronic



industries that disposed of metalplating wastes by means of



injection wells in Arizona.







In parts of Florida and Ohio, wells tapping limestone



aquifers have been used to dispose of domestic sewage from



individual homes.  Similarly, in Oregon  (Sceva, 1968, Oregon



State Sanitary Authority, 1967)  domestic sewage effluent is



discharged from septic tanks into deep rock wells drilled



into basalt aquifers (Figure C).  For the past several
                            101

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decades thousands of wells in New York, in California, and



in several midwestern states have been used to inject heated



water from cooling systems into fresh water aquifers.







In the Snake River Plain of Idaho, wells are widely used to



dispose of wastes into the underlying permeable basalt



aquifer.  A recent inventory in the area indicates that



there are approximately 1500 wells for disposal of surface



runoff and waste irrigation water, perhaps 2000 wells for



disposal of sewage, and additional wells for street drainage



and industrial use.  At the National Reactor Testing



Station, low->-level aqueous radioactive wastes have been



discharged into the same basalt aquifer through a drilled



well since 1953  (Jones, 1961).
                            102

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Land Surface

  _\   _
                                  Disposal Well
    '•;-.:;'-.: '••.;•''•••'• '".:.'-;v;-'. KO:.;': •••"':> ••'-• ^: ;^V'-. •'. ^ ydTT?^;
     f;iet:>:i^^^?^^^^
                                 ;V.:.-'./ Soil;
                                 ^'^Surface Casing
                                                 \
                                        1X   "N
                                             N

                                        ^   "X (
                                     Basalt
                                    - Rock   _  v

                                         \-  \
                                             S
                                                  /   \
                                              \
                                Crevices
Figure  C  Diagram of domestic sewage disposal system
           employing a disposal well in  the middle-
           Deschutes Basin,  Oregon  (after Sceva,  1968)
                           103

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In recent years, as pressure on municipalities to abate



pollution of surface waters has increased, greater attention



has been given to the possibility of injecting treated



municipal sewage into wells penetrating fresh water



aquifers.  Several of the proposed schemes not only would



solve a sewage-disposal problem but also would help to



recharge fresh-water aquifers or to establish hydraulic



barriers against salt-water encroachment in fresh-water



aquifers.  Advanced pilot experiments are being conducted



along these lines in Long Island (Vecchioli and Ku, 1972)



and in California (Baier and Wesner, 1971).  The procedure



is relatively costly because the sewage must be given at



least secondary treatment, and preferably tertiary



treatment, in order to prevent clogging the injection wells



and to reduce or prevent significant contamination of the



aquifer.







Modification of the existing quality of the native ground



water caused by subsurface disposal of wastes through a well



depends on a variety of factors including the composition of



the native water, the amount and composition of the injected



waste fluid, the rate at which the injection takes place,



the permeability of the aquifer, the type of construction
                            104

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and life expectancy of the well, and the kinds of biological



and chemical degradation that may take place within the well



and the aquifer.  In general, for economic reasons, wells



used for disposal of contaminated liquids in fresh-water



aquifers tap the shallowest available aquifer, commonly a



water-table aquifer.  Some disposal wells, however, are



terminated at greater depths in confined fresh water



aquifers.








Environmental Consequences




Initially, injection of contaminated liquids through wells



into fresh-water aquifers causes degradation of the chemical



and bacteriological quality of the ground water in the



immediate vicinity of the injection facilities.  Eventually,



the degradation spreads over a wider region and may



ultimately extend into surface waters that are hydraulically



connected with the receiving aquifer.  If the water-level



cones of depression around nearby operating water-supply



wells are large enough to include the injection site, or if



the wells are down-gradient along natural flow lines from



the injection site, contamination of these wells may take



place.  Another potential effect in some hydrogeologic



environments is irovement of the contaminated water from the
                            105

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injection zone into overlying or underlying fresh-water



aquifers.








Nature of Pollutants



The principal kinds of contaminated fluids that are



intentionally injected through wells into fresh-water



aquifers other than those from agricultural and mining



wastes, are cooling water, sewage, storm water, and



industrial wastes.








In the case of cooling water returned to the same aquifer



from which it has been pumped, the quality of the water may



be unchanged from that of the native water except for an



increase in temperature.  Increased solubility of aquifer



materials due to a rise in temperature is believed to be



insignificant, except perhaps in carbonate aquifers.  In



some instances sequestering agents,such as complex



polyphosphate-based chemicals added to the water to inhibit



oxidation of iron, may become a source of pollution to an



aquifer.








Domestic sewage being disposed of into individual household



wells is a waste highly polluted with organic and inorganic
                            106

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substances, bacteria, and viruses.  It may receive little



natural treatment during passage through septic tanks and



cesspools except for the settling of the solids, some



biochemical degradation of the wastes, and filtration of



part of the large bacterial population.  On the other hand,



the quality of the municipal sewage effluent released for



disposal into wells depends on the degree of treatment



before disposal and the source of the sewage.  Municipal



sewage generally consists mainly of domestic wastes with a



high content of dissolved solids, including nitrogen-cycle



constituents, phosphates, sulfates, chlorides, and



detergents (methylene-blue active substances, or MBAS).  In



some localities municipal sewage contains substantial



amounts of industrial wastes.  Different degrees of



treatment may remove or reduce the concentrations of certain



constituents, but even with the most advanced forms of



sewage treatment, many dissolved constituents, including



heavy metals, remain in the wastes.








The chemical qualities of tertiary treated sewage, native



ground water arid water recovered from observation wells,



from an experimental injection study in Long Island, New



York, are shown in Table 12.  The concentrations of ammonia.
                            107

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iron, phosphate, sulfate, and other constituents, as well as



the dissolved solids content,were significantly higher than



those of the native ground water.  No analyses of the



treated waste were made for heavy metal?, viruses, or other



objectionable constituents.  The bacterial count in the



treated sewage was low due to heavy chlorination before



injection.







Storm-water runoff generally has a low dissolved-solids



content.  However, the initial slug of storm water may be



contaminated with animal excrement, pesticides, fertilizer



nitrate from lawns, organics from combustion of petroleum



products, rubber from tires, bacteria, viruses, and other



contaminants.  Where deicing salts are applied to roads in



the winter, the chloride content of the storm water may rise



temporarily to several thousand mg/1.







Industrial wastes injected through wells range widely in



composition and toxicity, depending on the particular



industrial operation and the degree of treatment of the



wastes before disposal.  Plating wastes, pickling wastes,



acids, and other toxic materials, are some of the more
                            108

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common fluids disposed of through wells into fresh water

actuifers.
Contaminated Water Recoverd
from Observation Wells
Constituent
Total iron
Free CC-2
Fluoride
Ammonia nitrogen
Albuminoid nitrogen
Nitrite nitrogen
Nitrate nitrogen
Oxygen consumed
Chloride
Total hardness
Total alkalinity
PH
Total solids
MBAS
Calcium hardness
Total phosphate
Orthophosphate
Sulfate
Silica
Calcium
Magnesium
Sodium
Potassium
Tertiary Treated
Injection water
(mg/)2)
0.24
21
.26
25
.36
.00
<05
3
13
12
11
7.0
357
.02
42
3.6
3.1
137
14
18
5.2
69
11
Native Groundwater
Depth 171m
(mg/fi)
0.6
-
.01
-
—
_
.00
-
3.7
—
_
5.6
23
-
—
.01
-
4.1
7.4
.34
.17
3.7
.60
Depth 146m;
Distance 6.1m
(mg/£)
0.91
105
.23
18.5
.24
<.001
<.05
9
Lf
74
42
33
5.8
321
<.02
22
.60
.50
138
10
8.2
4.2
67
9
Depth 140m;
Distance 30m
(mg/B)
1.30
100
<.10
1.38
.04
<.001
<.05
1
24
34
6
5.1
123
<.02
16
.02
<.01
54
8.0
7.2
3.3
22
1.6
    Table 12  Selected chemical-quality characteristics of
              native water and tertiary treated injection
              water (after Vecchiolo and Ku, 1972) .
                            109

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Pollution Movement



In principle, any well that produces water will also accept



water.   The rate of acceptance is dependent on the nature of



the injected fluid, the hydraulic properties of the aquifer,



and other factors.  In some wells penetrating very permeable



aquifers, water can be introduced under gravity conditions



at rates that may be as high as several decaliters per



second or more without causing overflows.  In contrast, a



well penetrating a very poor aquifer may accept only a



fraction of a liter per second by gravity flow.  If pumps



are installed so that the fluid is injected under pressure,



the rate of injection can often be substantially increased.








The rate of injection is governed by the porosity,



permeability and thickness of the aquifer, the depth to the



natural water level in the well, the diameter of the well,



the area of openings in the well screen, and the chemical



compatibility of the injected fluid with the native ground



water.   If the fluid being injected contains suspended



materials or air bubbles, for instance, rapid clogging of the



aquifer can occur so that the injection rate falls off



sharply.  Growth of certain kinds of bacteria and formation



of chemical precipitates within the well and the adjacent
                            110

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aquifer also can interfere with injection.  In the case of a



water-table aquifer a further limitation on the rate of



injection is that an induced rise of the ground water level



may cause breakthrough and overflow at the land surface.







Injection of fluid through a well creates a local ground



water mound in an unconfined aquifer and a pressure mound in



a confined aquifer.  These mounds are essentially mirror



images of the water-level cones of depression that develop



around pumping wells tapping the same types of aquifers.



The configuration of a particular mound is generally



symmetrical, with the maximum rise in water level being



observed at the well.  Hypothetical shapes of contaminated



water bodies in homogeneous unconfined and confined aquifers



are shown in Figure D.  Departures from these shapes may



develop where aquifer lithologies are not uniform and where



the natural ground water flow is rapid.
                            Ill

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              WELL
                               Liquid contaminants
        — Aquiclude"^— —__—— — — — -—_—— ——- —

                     A.  Water table aquifer

                    WELL   _-*-" Liquid contaminants
                                at-New piezometric surface-
         Original— ^-^=*>	

                       B. Artesian aquifer
Figure D  Hypothetical pattern of flow of  contaminated
           water  (shaded) injected through  wells into
           water table and artesian  aquifers  (after
           Deutsch,  1963).
                           112

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After it has entered the saturated zone the injected fluid



begins to move radially away from the well, displacing the



native qround water in its path and creating a zone of mixed



water along the perimeter of the contaminated body.  The



polluted water mcves slowly in the direction of the



hydraulic gradient toward a point of discharge which may be



a well, a spring, or a surface-water body.  Where  injection



wells leak due to corrosion, casing breaks or poor



construction,the contaminated water may move into  fresh-



water aquifers above or below the injection zone.








Ex a m21 e s_ o f _t he _ Us e_o f _I n jec t i on_ We 11 s



Since 1965 a pilot experiment on recharging tertiary-treated



sewage in order to create a hydraulic barrier against



salt-water encroachment has been conducted by the U.S.



Geological Survey,in cooperation with the Nassau County



Department of Public Works,at Bay Park, Long Island



(Vecchioli and Ku. 1972).  A specially constructed injection



well (Cohen and Eurfor, 1966), 146 meters  (480 feet) deep,



with a fiberglass casing, stainless steel screen,  and



auxiliary monitoring wells at depths ranging from  about 30



to 200 meters (100 to 700 feet), were installed to



investigate the hydraulic and geochemical problems
                            113

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associated with the injection of treated sewage into a



confined.sand aquifer used for public-water supply.  The



injected water moved radially from the well as a thin body



in the injection zone and has been detected by monitoring



wells as much as 60 meters (200 feet)  away.  As shown in



Table 12, significantly higher concentrations of iron,



ammonia, sulfate, chloride, sodium, and other dissolved



constituents were present in the water at distances of 6.1



meters and 30.5 meters (20 feet and 100 feet), than in the



native ground water.  Bacteria were apparently filtered out



after about 6.1 meters (20 feet) of travel.  The



experimental results indicated that even low turbidity of



the effluent and bacterial growth around the well screen can



cause clogging and excessive head build up in the injection



well.  Similar experiments in California on recharging fresh-



water aquifers with Colorado River water and with reclaimed



sewage  (McGauhey and Krone, 1954), mainly as a barrier



against sea-water encroachment, have been successfully



conducted.  Some barrier systems using highly treated river



water are operational.  Baier and Wesner (1971) have



described experiments by Orange County Water District in



which tertiary-treated effluent from a trickling filter



sewage plant was injected into unconsolidated aquifers at
                             114

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depths of about 30 to 100 meters  (100 to 350 feet).  The



experiments indicated that after about 150 meters  (500 feet)



of travel, the injected water was free of bacteria  and



toxic substances, and the ammonia content was substantially



reduced.  However, the hardness and alkalinity of the water



increased, the water had a musty odor and taste, and the



dissolved solids content exceeded 1,000 mg/1.  Additional



pretreatment of the reclaimed waste water will improve the



quality of the water intended for injection, and the



dissolved-solids content will be reduced to drinking water



standards by mixing reclaimed waste water with desalted sea



water before injection.







Since the early 1930's, the State of New York has required



that water pumped from wells on Long Island at rates of 2.8



Ips (45gpm)  or more must be returned, through a closed



system of specially constructed recharge wells, into the



same aquifer from which the water was pumped.  This



requirement was imposed because heavy pumping had caused a



sharp decline in ground water levels in western Long Island,



with coastal encroachment of sea water.  The heated effluent



returned to the ground, which may range from 5 to 17<>C



warmer than the natural ground water, has increased the
                            115

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local temperature of shallow aquifers (Leggette and



Brashears, 1938) .  Warming of the ground water, although of



concern to users of ground water for cooling, has been



regarded as less detrimental than the saltwater encroachment



that could result from declining ground water levels.








In parts of western Long Island, stormwater that collects at



street intersections subject to flooding is disposed of into



dry wells that act as drains.  The wells are lined with



large-diameter, precast, perforated concrete rings.  The



stormwater moves downward through the wells into a shallow



aquifer.  Hundreds of dry wells are also used for highway



drainage in other parts of the country; notable are those in



the Fresno area cf California  (Gong-Guy, in Schiff, 1963).



In a few places, wells also have been drilled within ponds



to drain them.  Erainage wells commonly provide a bypass for



potential vertical movement of inorganic and organic



contaminants and bacteria into an underlying aquifer.








Control^Methods




Where injection of wastes through wells into fresh-water



aquifers is proposed   r is in progress, a hydrogeological



investigation shculd be undertaken as a first measure to
                            116

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control potential ground water pollution.  This should



include:








    1.    Definition of the hydrogeologic environment and the



         factors affecting the ground water flow.








    2.    Existing or planned nearby wells should be located.








    3.    The directions and rate of movement of the



         potential contaminated fluid should be ascertained



         so that estimates can be made of how much time will



         elapse before the arrival of the contaminated water



         at nearby wells.








    4.    Studies should be undertaken to determine the



         possibility of inter- and intra-aquifer movement of



         the injected water.








    5.    Information should be compiled on the chemical,



         biological, and physical properties of the waste



         fluids; the degree of pretreatment needed; and the



         compatibility of the treated fluids with the native



         ground water.
                            117

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    6.   An evaluation should be made of the most suitable



         locations and spacings of injection wells and of



         the rate of injection.







    7.   Consideration should also be given to future land



         use at the injection-well sites.







Where the threat from contaminated ground water is severe,



steps may have to be taken to block the underground flow of



the waste fluids or to actually remove the fluids by



pumping.  Blocking of the movement of the contaminant can be



accomplished by constructing physical subsurface barriers



although this is net an economically feasible solution in



most hydrogeologic environments.  Diverting the flow by



creating a hydraulic barrier is another approach that may be



implemented in many places.  This can be accomplished by



injecting fresh water through wells installed across the



path of flow or by pumping from wells so as to induce the



contaminants to flew toward these wells.







Pumping polluted fluids back out of the ground may create a



new pollution problem where the wastes are pumped into



surface water.  However if facilities can be provided for
                            118

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prooer treatment and disposal of the pumped water,  pumping



from wells can be a practicable solution.








Alternatives to disposing of wastes through injection



should, of course, be examined.  A careful evaluation of



alternatives is required to avoid adopting an expedient that



may prove to have ether, and perhaps more harmful,  effects.



Sewering for example, which exports the waste, can  have



deleterious effects due to loss of recharge and consequent



lowering of water levels,possibly causing salt-water



intrusion.  In the case of cooling water being returned to



the aquifer from which it is drawn an alternative is to use



atmospheric heat exchangers instead of cooling water.  Here



the loss of efficiency of the cooling system must be



considered; more electrical energy may be required, with



attendent air and thermal pollution problems.  Also the



undesirable "heat island" effect noted in large cities would



be further increased by widespread use of atmospheric heat



exchangers in place of the ground water for cooling.








Halting the disposal of wastes into wells may, in some



instances, be highly desirable but it should be noted that



halting the injection represents only a partial  pollution
                            119

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control measure; fluids already injected will continue to



pollute the aquifer.







MpHi£ or inc[_ Procedures



After a clear understanding has been developed of the



hydrogeologic environment and of the mechanisms of



contamination, a monitoring system should be designed and



implemented to provide continuing surveillance of polluted



water, and of the efficiency of any control measures that



may be instituted.  Depending on local conditons it may be



necessary to construct a series of wells at different depths



in the polluted aquifer and at scattered nearby locations.



Periodic monitoring of these wells for chemical content of



the ground water, and changes of ground water levels, can



provide valuable data on the behavior of the underground



contamination,and on the environmental threats to water



wells or to other fresh-water resources in the vicinity.
                            120

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References
1.   Baier, D.C., and Wesner, G.M., "Reclaimed Waste Water
    for Ground-Water Recharge," Jour. American Water
    B§ sources Assoc^^ v.7, no. 5, pp. 99T~TooT  (T971)".
2.   Cohen, Philip, and Durfor, C.N, ,  "Design and
    Construction of a Unique Injection Well on Long  island,
    New York," geological Survey Research, ^96^ U..  S.  Geol^
    Survey Prof7~Papjer 550-D^ pp. D253-D257  (1966).

3.   Deutsch, Morris, Ground-Water Contamination and  Legal
    Controls i.n Michicjan^ U." S, Geol. Survey Water-supply
    Paper 1691, 79~pp.   (1963) .

4.   Fuhriman, O.K., and Barton, J.R., Ground Water Pollution
    in Arizona^. Calif or niax Nevadax and Utah^ U. S.
    Environmental Protection Agency,  Water Pollution Control
    Research Series 16060, 249 pp.  (1971).

5.   Jones. P.H. , Sydrology of Waste Disposal National
    Reactor Testing Station^ .IdahOj. U. s. Geol. Survey
    Interim Report for U. s. Atomic Energy Comm. , Idaho
    Falls, Idaho  (1961) .

6.   Leggette, R.M. and Brashears, M.L., Jr., "Ground Water
    for Air Conditioning on Long Island, New York,"  Trans.
    Amer., Geoghys^  Union^ pp. U12-U18  (1938).           "

7.   McGauhey, P.H. , and Krone, P. B. ,  Report on the
    Investigation cf Travel of Pollution^ California State
    Water Pollution Control Board, Publ. no. 5, 218  pp.
    (1954) .

8.   Oregon State Sanitary Authority,  Water .Quaj-ity Control
    iEt Qregon, Oregon State Sanitary  Authority, vol.  1,  113
    pp. (1967).

9.   Sceva, J.E. , Liquid Waste Disposal j.n the Lava Terr an es
    2l Ceirtrs! Orecjonx U. S. Federal Water Pollution  Control
    Admin., Northwest Region, Pacific Northwest Water
    Laboratory, Corvallis, Oregon  (1968).
                             121

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10.  Schiff,  Leonard, (Editor), Ground Water E§£|j3rge and
    Ground Water Basin Managementf Proc. 1963 Biennial
    Conference Ground Water Recharge Center, Fresno, Calif.
    (1963) .

11.  Vecchioli, Hchn, and Ku, F.H., Preliminary Results of
    iQJSSiiDS Siahly Treated Sewage Plant Effluent into a
    Deep and Sand^Aquifer at Ba^ Parkx New York^ U. S. Geol,
    Survey Prof .~Paper 751A7 "l4 pp. (1972) .
                             122

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 SECTION III - POLLUTION FROM OTHER SUBSURFACE EXCAVATIONS








LAGOONS, BASINS, AND PITS








In general, a lagoon comprises a natural depression in the



land or a sector of some bay, estuary, or wetland area diked



off from the remainder.  No sharp line of definition



distinguishes it from a basin, which is most commonly



constructed by formal diking or by a combination of



excavating and diking.  Pits are distinguished from lagoons



and basins by a smaller ratio of surface area to depth.








Unlike excavations used in septic systems or in landfill



operations, lagocns, basins, and pits are usually open to



the atmosphere, although pits and small basins may sometimes



be placed under a roof.  Some are intended to discharge



liquid to the soil system and hence to the ground water,



others are designed to be watertight.  The former are,



therefore, unlined structures sited on good infiltrative



surfaces; the later are lined with puddled clay, concrete,



asphalt, metal, or plastic sheeting.  Thus, both by design



and by accident or failure, this type of structure is of



concern in the context of ground water quality.
                            123

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Lagoons and basins are adapted to a wide spectrum of



municipal and industrial uses including storage, processing,



or waste treatment on a large scale.  For example, the



unlined lagoon or basin may serve as a large septic tank for



raw sewage, a secondary or tertiary sewage oxidation pond,



or as a spreading basin for disposing of effluent from



treatment ponds cr conventional waste water treatment plants



by ground water recharge.  In industry the unlined system



may serve as a cooling pond or to hold hot waste water until



its temperature is suitable for discharge to surface waters,



or to store waste water for later discharge into streams



during flood flows or for application to the land during the



growing season.  Seme unlined lagoons are used for a special



purpose, such as evaporating ponds, to concentrate and recover



salt from saline water.  Lined basins are used for a number



of purposes, including evaporation ponds for concentrating



salts or process brines.  Recovery of minerals, or more



economic disposal of the concentrate, may be the motivating



factor.  In oil fields, refineries, and chemical processing



plants, lined pits are used as holding sumps for brines or



wastes as a stage in disposal by well injection,or other



acceptable procedure.  In the East Bay area of California, a



lined basin has served as a receiving sump for fruit and
                            124

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vegetable cannery wastes to be barged to sea or hauled to



land disposal sites.







Unlined pits serve to a limited extent in sewerage; examples



include pit privies and cesspools or percolation devices in



septic systems.  They are also widely used to dispose of



storm water from roof drains.  In California both pits and



basins are used to dispose of storm water which would



otherwise collect in highway underpasses and interfere with



traffic.







Lined pits have historically been used in industry for



processes ranging from tanning of animal hides to metal



plating.  They are commonly used to house sewage pumps below



the ground level.  In both industry and municipal sewerage,



they are used as intake sumps in pumping installations.



Although lined pits are commonly concrete or metal



structures, undetected leakage of highly concentrated



pollutants can have a significant effect on ground water.







Sc o£e_ of_P r ob le m



Data by which to evaluate the existing scope of the problem



of municipal and industrial waste lagoons and similar open
                            125

-------
excavations in relation to ground water quality have not



been assembled and analyzed.  State health departments and



water quality control boards can cite instances in which



ponded contaminants have created a local pollution problem.



To assess the degree to which the use of lagoons, basins,



and pits in fact degrade ground water quality will require



an extensive survey of the literature and of the practice of



ponding wastes and process materials.  The present outlook



is that the need for such an assessment will become



increasingly great with time.  Two factors support this



conclusion:








    •    As institutionalized in Public Law 92-500, there is



         a growing reluctance of regulatory agencies to



         permit waste discharges to surface waters, thus



         requiring either land disposal of sewage effluents



         or the creation of an increasing volume of process



         brines in achieving an acceptable effluent quality; and



    •    A growing tendency to require industry to process



         its own wastes prior to discharge to the municipal



         sewer, thus creating more need to use lagoons and



         basins either for waste processing or for managing



         waste processing brines.
                             126

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Both of these developments suggest a need to control the



pathways by which contaminants may move from ponds to ground



water and to monitor the effectiveness of control measures.








Potential Hazard tc^Ground Water



The potential of sewage lagoons to degrade ground water



quality is essentially the same as that of septic systems.



An extensive survey of the literature  (McGauhey and Krone,



1967)  shows that a continuously inundated soil soon clogs to



the extent that the infiltration rate is reduced below the



minimum for an acceptable infiltration system.  If the



ground water surface is too close to the lagoon bottom, a



hanging column of water will be supported by surface tension



and the soil will not drain.  Clogging will then continue



indefinitely even though no new liquid is added to the



system.  A spreading pond designed to discharge effluent to



the ground water must, therefore, be loaded and rested



intermittently to maintain an acceptable recharge rate.  If,



however, isolating the contents of the lagoon from the



ground water is the objective of the system, a low



infiltration rate may still mean an undesirable quantity of



polluted water passing the water-soil interface.  The



pollutants carried downward with percolating water from a
                            127

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sewage lagoon are those described in the section on septic



tanks.  Not all of the salts introduced to the ground water



originate in domestic use.   In some instances, such as that



of Colorado River water delivered to Southern California,



the mineral content of the imported water may be higher than



that of the local ground water.








Liquids percolating from lagoons or basins used by industry



have a greater potential to degrade ground water than does



domestic sewage.  Chromates, gasoline, phenols, picric acid,



and miscellaneous chemicals have been observed to travel



long distances with percolating ground water.  Unlined



lagoons, basins, and pits are commonly used by industry for



the storage of liquid raw materials and waste effluent.



Most of these facilities are simply open excavations or



diked depressions in which the liquid is temporarily or



permanently stored.  Few have been designed with proper



consideration to water tightness, so that leakage of



potential contaminants into the underlying ground water



reservoir is very common even though the leakage may seldom



be known to exist.  Liquids stored in industrial lagoons,



basins, and pits may contain brines, arsenic compounds,
                            128

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heavy metals, acids, gasoline products, phenols, radioactive



substances, and many other miscellaneous chemicals.








Where storage areas have been actively used for many years



and leakage through the sides and bottom of a particular



lagoon or basin has taken place, the quantity of



contaminated ground water can be significant and the plume



of polluted liquid may have traveled long distances with the



percolating ground water.  In some instances, the first



realization that extensive ground water pollution has



occurred may come when the plume reaches a natural discharge



area at a stream and contamination of surface waters is



noted.








An example of the fate and environmental consequences of a



leaky basin containing metal^plating waste effluent from an



industrial plant is given in Perlmutter and Lieber (1970).



Plating wastes containing cadmium and hexavalent chromium



seeped down from disposal basins into the upper glacial



aquifer of southeastern Nassau County, New York.  The



seepage formed a plume of contaminated water over 1200



meters (4,000 feet) long, about 300 meters (1,000 feet)



wide, and as much as 20 meters  (70 feet)  thick.  Some of the
                            129

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contaminated ground water is being discharged naturally into



a small creek that drains the aquifer.  The maximum observed



concentration of hexavalent chromium in the ground water was



about. 40 mg/1, and concentrations of cadmium have been



observed as high as 10 mg/1.








In another case in New Jersey, unlined waste lagoons



constructed in sand and gravel beds leaked over 75 million



liters  (20 million gallons) of effluent into the upper 6



meters  (20 feet) of aquifer over a period of only a few



years.  The contaminated ground water contains high



concentrations of phenols, chromium, zinc, and nickel.








Control,Methods




In the case of lagoons or basins for deliberate disposal of



sewage effluents, or surface runoff by ground water



recharge, controls specifically pertinent to ground water



protection are essentially self-generating — the system



simply will not work if not properly designed.  The first



control measure in ground water protection from spreading



basins is to apply existing knowledge to their siting and



design.  Existing engineering and hydrogeologic knowledge



would prohibit the construction of such systems directly in
                            130

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the aquifer; require adequate distance between the



infiltrative surface and the ground water surface to permit



drainage; and prohibit construction in faulted or fractured



strata or in unsuitable soils.







Control of industrial waste discharges to the ground water



is a complex problem.  In a state with a highly organized



water pollution control agency (e.g., California), individual



permits are issued on the basis of adequate design and



surveillance programs.  Because of the variety of industrial



wastes and the varied situations in which they occur,



control of ground water pollution from such wastes depends



both upon proper design of new systems and upon discovery



and correction of existing poor systems.  Methods for



controlling ground water pollution from industrial lagoons,



basins, and pits include:







    •    Pretreatment of wastes for removal of at least the



         toxic chemicals.



    •    Lining with impervious barriers of all lagoons,



         basins, and pits that contain noxious fluids.  This



         is the principal control technique recommended by
                            131

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         some agencies,  such as the Delaware River Basin




         Commission.



    •    Use barrier wells,  pumped to intercept plumes of



         contaminated ground water from existing industrial



         basins where leakage has occurred.  Such wells have



         been used successfully, but can be costly to



         install and operate.  The water removed must be



         treated before  redisposa}..



    •    Banning the use of  pits.  An example is found in



         Kansas, where thousands of brine pits were used by



         the oil industry.  Kansas was the first State to



         ban their use because of the contamination of



         ground water.



    •    Locating and identifying unauthorized pits on



         industrial sites, on a case-by-case basis, and



         apply appropriate regulatory action.








Monitoring Procedures



Lagoons, basins, and pits represent pollution sources which



may be of significance to ground water quality degradation.



Therefore, a program involving special monitoring wells on a



priority basis is a possible approach.
                            132

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A program of periodic sampling and evaluation of data from



existing wells, selected for their potential to reveal both



normal ground water quality and point contamination, is



another monitoring approach.  Accompanying this should be an



evaluation of the control measures themselves to assure that



ground water protection is indeed being accomplished.
                            133

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References
1.  Anon., "Well Pollution by Chromates in Douglas,
    Michigan," Michigan Water ^ Works News  (1947).

2.  California State Water Pollution Board, Wastewater
    Rec la mat ion in Re la ti on to Grgundwater^ Pollution ,
    Publication No. 6, Sanitary Engineering Research
    Laboratory, University of California, Berkeley  (1953) .

3.  Davids, H.W. , and Lieber, M. , "Underground Water
    Contamination by Chromium Wastes," Water and Sewage
    Works , Vol. 98, pp 528-534  (1951).

4.  Geraghty & Miller, Inc. , Consultant* s Report, Port
    Washington, Ne* York  (1972) .

5.  Harmond, B. , "Contamination of Groundwater Resources,"
                             H» P 343  (1941).
6.  Lang, A., "Pollution of Water Supplies, Especially  of
    Underground Streams, by Chemical Wastes and  by  Garbage,"
     Z-^Gesundheitstech^ &_Stadtehy.2- (Ger.) , Vol.24,  No. 5,
    p 174 (1932) .

7.  Lang, A., and Gruns, H. , "On Pollution  of Groundwater  by
    Chemicals," Ga^_ui_Wasjer, Vol. 83, No. 6; Abstract,
    JOU£BSi_^IDSJiS3n__Water_Works_A^soca.atig5i/ Vol.  33,  p
    2075  (1940) .

8.  McGauhey, P.M., and Krone, R.E., Soil Mantle as a
    Wastewater  Treatment System, Final Report SERL  Report
    No. 67-11,  Sanitary Engineering Research Laboratory,
    University  of California, Berkely  (1967) .

9.  McGauhey, P.H. and Winneberger, J.H. , Causes and
    H-E^ZSHtion  2J failure of Septic-Tank Percolation
    Systems, Technical Studies Report, FHA  No. 533, Federal
    Housing Administration, Washington, D.C.   (1964).

10, Muller, J. , "Contamination of Groundwater Supplies  by
    Gasoline,"  Gas u. Wasser,Vol. 93, pp 205-209 (1952) .
                            134

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11.  Perimutter, N.M., and Lieber, M., Dispersal of  Plating
    W§§^SS §nd Sewage Contaminants in Ground Water  and
    SU£f§ce Watery South Farmingdale-Massapegua Are a, Nassau
    County, New York,U. S. G. S. , Water Supply Paper 1879-G,~"67
    op (1970) .

12.  Sayre, A.N., and Stringfield, V.T., "Artificial Recharge
    of Groundwater Reservoirs,"  Journal of American^ Water
    Works Association,Vol. 40, pp 1152-1158  (1948).
                            135

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SEPTIC SYSTEMS



Scope of the^Prgblem



Septic systems are used in every state in the Union, the



heaviest concentration being in suburban subdivisions



developed following World War II and in recreational lake



development.  The predominant type of system is the



individual household septic tank.  From data available from



the Public Health Service and the Federal Housing



Administration, it is estimated that 32 million people were



served by septic tanks in 1970.  In addition to the total



subsurface percolation systems associated with these



installations, there are an unestimated number of summer



cabins. Forest Service campgrounds, and organized group



camps which depend upon subsurface disposal of waste water,



primarily during the summer season.







Although the septic tank with an associated subsurface per-



colation system is the most commonly used type of septic



system, raw sewage is still discharged directly from the



plumbing system of the house into cesspools dug in the



ground.  The practice is no longer approved for new



installations.  Nevertheless, they may be found in the



United States wherever soil conditions make the cesspool
                            136

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feasible.  In New York State there are probably 100,000 or



more such installations.  In less populous areas such as New



England, the Southwest, and the Northwest, cesspools are



known to exist.  Several thousand such systems discharging



into lava tubes are still in use in Hawaii.








The relationship between a septic sytem and the quality of



nearby ground water is governed by the design and control of



the system.








The septic tank is a water-tight basin intended to separate



floating and settleable solids from the liquid fraction of



domestic sewage and to discharge this liquid, together with



its burden of dissolved and particulate solids, into the



biologically active zone of the soil mantle through a



subsurface percolation system. The discharge system may be a



tile field, a seepage bed, or an earth-covered sand filter.



In some instances, as in the vicinity of Sacramento,



California, where the soil is sandy and the water table far



below the surface, seepage pits are used.  These are drilled



holes some 75 centimeters (30 inches)  in diameter extending



down   to  a depth of 6 meters (25 feet)  or more, and filled



with gravel surrounding a wooden center frame.
                            137

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In the cold Northern and Northeast regions of the United



States, tile fields are located below the frost line.  This



places them below the biologically active zone of the soil.



In low lands, notably in the South, a high ground water



table makes it necessary to place the percolation system



above the normal ground level.  Here a one meter (three



foot) deep, soil-covered sand bed is used.  It discharges



back to standing water in the swamps or road drainage



ditches if it cannot percolate directly into the ground



water.







In a percolation system located in the biologically active



zone, biodegradable organic matter is stabilized by soil



bacteria, particulate matter is filtered out, and certain



ions  (e.g., phosphate) are adsorbed on the soil.  Liquid



passing through the active soil zone percolates downward



until it strikes an impervious stratum or joins the ground



water.  In the growing season, a portion, or even all, of



the septic tank effluent may be discharged to the atmosphere



by evapotranspiration.  Salts not incorporated in the plant



structure are left in the root zone to be redissolved and



carried downward by percolating water.  Thus, the purpose of



the percolation system is to dispose of sewage effluents by
                             138

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utilizing the same natural phenomena which lead to the



accumulation of ground water.







If the percolation system is below the biologically active



zone of the soil, filtering and adsorption phenomena



predominate.  Biodegradation in the system is confined to



the partial degradation of organics under anaerobic



conditions.







Environmental Congeguences



Two categories of environmental effects which bear upon



control measures may be identified:







    •    Those which lead to restrictions on the use of



         septic systems.



    •    Those which are inherent in a properly designed and



         well-functioning septic system in suitable soil.







Under the first category three situations may be identified.



Most common of these is the failure of percolation systems,



which creates a hazard to health and an unacceptable



nuisance as decomposing sewage effluent appears on the



surface of the ground.
                            139

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The second and more serious situation in the context of



ground water quality is direct discharge of untreated septic



tank or cesspool effluent into the ground water through



coarse gravel beds, fractured rock, solution channels, or



lava tubes.  In some areas of the United States, a local



practice is to cut trenches directly in bedrock and then



shatter the rock with explosives to create drainage



channels.  Hawaii was mentioned earlier as an area where



cesspools are dug into lava tubes.  In all of these cases,



the ground water itself often carries for long distances



putrescible sewage solids, bacteria, viruses, tastes and



odors, with consequent danger to health and impairment of



the aesthetic acceptability of water.







The third situation is somewhat similar to the second.  It



occurs when percolation systems are located below the



biologically active zone, which typically is only a meter or



so in depth.  Such systems may be installed where the frost



line is deeper than the biologically active zone, or they



may simply be buried too deeply because of lack of



understanding of proper construction techniques.   (Long



Island is perhaps the most publicized case where percolation



systems are commonly to be found below the biologically
                            140

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active soil zone.)   In such a situation, biodegradation in



the system is confined to the partial degradation of



organics under anaerobic conditions; the physical phenomena



of filtering and adsorption remain effective, but soluble



products of partial breakdown of organic matter may enter



the ground water and move with it.  Tastes and odors are



introduced, and the organic fraction, being biochemically



unstable, remains capable of supporting bacterial growth



when the ground water outcrops or is withdrawn through a



well.







It may be said that at best septic systems increase the



total dissolved mineral solids in ground water.  At worst,



they may introduce bacteria, viruses, and degradable organic



compounds as well.   The multiple-point nature of septic



system inputs tends to minimize the concentration of



pollutants in any unit of receiving ground water.  In some



local situations the effect may not be measurable by normal



analytical tests.  In other local situations such as Long



Island, New York, and Fresno, California, where numerous



septic systems are installed in a single subdivision, the



effect on local ground water has been readily detected.
                            141

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Control Methods



Control of the effects of septic systems on ground water



quality must be considered in three situations:







    1)    Septic tank installations are already in existence.



    2)    New septic tank systems are to be installed.



    3)    No practical alternative to the septic tank is



         presently feasible.







Of these situations, the first is the most difficult to deal



with because design is beyond recall and degradation of



ground water may have already occurred,  of course, if



system failure is involved, the situation is largely self-



curative.  The inability of soils to transmit effluent to



aquifers results in its appearance on the land surface and,



if the subdivision involved is of any significant size, to



an early replacement by conventional sewerage.  However, if



an existing system is functioning satisfactorily, its total



contribution of salts co the ground water can be computed



from an analysis of the water supply and the known



contribution of salts from domestic use.  The actual



immediate effect of any installation large enough to produce



measurable results may be estimated by monitoring the top of
                            142

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the ground water body.  The control program would then



involve mandatory monitoring and judgment of the



significance of the results by competent hydrogeologists.



Several control procedures are applicable, viz.,








    •    Require any existing subdivision subject to septic



         system failure or observed by mandatory monitoring



         to be damaging to ground water quality to enter



         into sewerage districts with collection and



         treatment facilities.



    •    Require householders to connect to a sewer as urban



         development fills in the open land that once set



         the subdivision apart from an urban center, or as



         land development extends the populated area beyond



         the initial subdivision.



    •    Prohibit the home regeneration of water softeners



         where septic systems are used for waste disposal.








In a situation where new septic tank installations are



proposed, possible measures for control include:








    •    Require approval of the site and design by



         competent hydrogeologists, soil scientists and
                            143

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engineers before septic systems are approved for



any proposed subdivision, recognizing that simple



percolation tests (USPHS, 1968) and standard codes



offer only inadequate criteria for the design of a



septic system.



Construct percolation systems by methods which do



not compact the infiltrative surface  (McGauhey and



Winneberger, 1964),  including:







--   No heavy equipment upon infiltrative surfaces.



—r-   Trenching, boring, or excavating for



     percolation systems only when soil moisture is



     below smearing level.



     Use cf trenching equipment which does not



     compact trench sidewalks.



     Use cf classified stone sizes in backfills to



     produce "clogging in depth"  (McGauhey and



     Winneberger, 1964).



     Utilize level bottom trenches with observation



     well risers at each end of each tile line.








Operate septic systems effectively by:
                   144

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         —   Alternately loading and resting one-half the



              percolation system; the cycle to be determined



              by the onset of ponding in the system at the



              observation well.



              Where size of system makes it practicable,



              loading the entire infiltrative surface of the



              system at each cycle as uniformly and



              sirrultaneously as possible by use of a dosing



              siphon.



              Inspecting and removing scum and grease from



              septic tanks annually.



         —   Drawing off half of the sludge rather than



              pumping out the entire contents of tanks.








    •    Use of zoning and other land management controls to



         prevent septic system installations in unsuitable



         soils (i.e., soils too impervious to accept



         effluents, or too coarse or fractured to maintain a



         biological and physical treatment system).








In situations where no practical alternative to septic



systems is presently feasible, the alternatives are to:
                            145

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    1.    Limit use of septic systems to the growing season



         for vegetation.



    2.    Permit the use of septic tanks if soil is suitable,



         and accept the consequences in terms of ground



         water quality.



    3.    Permit use of septic systems but restrict the



         materials which may be discharged to them,



         specifically, by prohibiting the installation and



         use of household water softening units which are



         regenerated on the site.



    4.    Permit the use of septic tanks under specific



         conditions.







The first alternative is applicable to such installations as



forest camps,  summer cottages, and summer camps in remote



areas where evapctranspiration and plant growth consume most



of the water and nutrients.  The subsequent pickup of salts



in the root zone is done by relatively large amounts of



meteoric water.







The second alternative is essentially necessary in the case



of isolated dwellings on relatively large plots of land



remote from any sewer.
                            146

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The fourth alternative is an appropriate control measure



where soil is suitable and good design and operating



procedures are followed.  Specifically, it may require that



sewers be provided in the streets of a housing development



and that house owners abandon septic systems and connect to



the sewer when it is available.  A 5- or 10-year maximum



permit to use septic tanks can be specified,
Assuming that unsatisfactory systems are to be controlled by



regulatory action or replaced as a result of failure,



monitoring procedures would be confined to analyses of



percolating waste water and of the receiving ground water,



and to requirement of permits and inspection for any



softener installations or other connections to the household



plumbing system.







Technologically, the use of Tensiometers for sampling



percolating water in both unsaturated and saturated flow



conditions is a well-established routine.  Questions to be



answered in the case of a subdivision based on septic



systems are: who is to make the installations, where are



they to be located, and how continuously are they to be
                            147

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observed and replaced.  The most likely method would be to



evaluate the percolate on the basis of an analysis of the



water supply, and of a seasonal analysis of percolate



obtained from a short-term field study in one or more septic



tank percolation fields.  Fundamentally, this procedure



yields baseline data but is not in itself a monitoring



sytem.  In general, the monitoring of septic system



percolate is probably an unnecessary and unrewarding



procedure.








If ground water receiving percolate from overlying septic



systems is to be monitored, it is desirable to sample both



at the water table and at greater depths.  Bacteria,



although they should not be present as a result of



percolating sewage effluents, tend to concentrate in soil at



the water table.  Greases and oils which might be discharged



by the householder also tend to float on the ground water.








Pragmatically, monitoring may prove to be necessary in order



to verify technological predictions that degradation of



groundwater quality will occur because of prolonged and



concentrated use of sf. tic systems.  In Suffolk and Nassau



Counties on Long Island, measurements of the degradation of
                            148

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ground water quality were a major factor in making decisions



to install sewers and treatment plants.  (Other factors also



enter into the decision, of course; for example, loss of



local recharge may cause lowering of the water table when



sewers collect effluent and discharge it to a stream or



coastal waters.)
                            149

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References
1.  Bendixen, T.Vi., et al.. Study to Develop Practical
    S^sign Criteria! for Seepage Pits as a Method of
    D.isJ2°.5<|l of S§Eii£~Tank Effluent, Report to FHA, Robert
    A. Taft Sanit.Eng. Center,~USPHS, Cincinnati  (1962).

2.  Coulter, J.E., et al., Study of Seepage Beds, Report  to
    FHA, Robert'ft. Taft Sanit. Eng. Center, USPHS,
    Cincinnati  (1960).

3.  McGauhey, P.H., and Winneberger, J.H., Soil Mantle  as a
    Wastewater Treatment System, Finai Report, slRL Sept.
    No. 6_T-_11X Sanitary Engineering Research Lab., Univ.  of
    California, Berkeley (1967).

4.  McGauhey, P.H., and Winneberger, J.H., Causes and
    H££¥§Biion of Failure Qf Septic-Tank Percolation
    Systems, Tech. Studies Rept., FHA No. 533, Federal
    Housing Administration, Washington, D.C.  (1964).

5.  Perlmutter, N.W., and Guerrera, A.A., "Detergents and
    Associated Contaminants in Ground Water at Three Public-*
    Supply Well Fields in Southwestern Suffolk County,  Long
    Island, New York," U. S. Geol. Survey, Water-Supglv^
    £aper_2001-B, 22 pp  (1970) .

6.  Schmidt, D. E. , "Nitrate in Groundwater of the Fresno-
    Clovis Metropolitan Area, California,"  Ground Water,
    v.10, no., 1 pp. 50^64  (1972).

7.  U. s. Public Health service, Quad-City Solid Wastes
    EE23§ct - An Interim Report, July 1, 1966 to May 13,
    1967, USPHS, Cincinnati  (1968).
                             150

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LANDFILLS



The Matter of Definition

To evaluate the effects of land disposal of solid wastes in

the context of "landfills" it is necessary to recognize an

unfortunate lack of distinction between the properly

designed and constructed sanitary landfill   and the variety

of operations that are properly classed as refuse dumps.  A

landfill is herein defined as any land area dedicated or

abandoned to the deposit of urban solid waste regardless of

how it is operated or whether or not a subsurface excavation

is actually involved.  A "sanitary landfill" is:
    "A method of disposal of refuse on land without creating
    nuisances or hazards to public health or safety, by
    utilizing the principles of engineering to confine the
    refuse to the smallest practical area, to reduce it to
    the smallest practical volume, and to cover it with a
    layer of earth at the conclusion of each day's operation
    or at such mere frequent intervals as it may be
    necessary."
Less than 10 percent of the refuse disposal sites in the

United States are operated within this accepted definition

of a sanitary landfill.  Very few of those considered true

sanitary landfills were established in sites studied and
                            151

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selected for the special purposes of hazardous waste
disposal.

Urban, or municipal, solid waste is considered to include
household, commercial, and industrial wastes which the
public assumes responsibility for collecting.  However,
commercial solid waste and industrial solid wastes, presently
collected and hauled privately, may be discharged into a
public landfill, along with municipal wastes and refuse
which the citizen himself delivers.
              2 °D s eguence s
The potential hazard of landfills to ground water quality
via leachate is a function of the total amount of waste
generated, its areal distribution, the composition of the
waste itself, and the siting, design, and operation of the
fill.  The U.S. Environmental Protection Agency estimated
that in 1969 urban solid waste totaled 225 million tons per
year, while industrial solid waste was about 100 million
tons.  Various estimates of this total for 1972 are about
one ton  per capita per year — almost 2.72 kilograms per
person per day.  In 1970 there were some 16,000 authorized
land disposal sites, and perhaps 10 times that many
                            152

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unauthorized dumping grounds.  Because wastes are generated



and disposed of where people are, the pattern of population



distribution gives a clue to the location and intensity of



landfill practice.








Typical values of components of solid wastes collected in



urban communities are shown in Table 13.  From this Table it



may be concluded that slightly over 70 percent of domestic



refuse is biodegradable organic matter of which about three-



quarters (50 percent of total waste) is paper and wood.  An



additional fraction ranging from 1 to 15 percent in the



Table involves materials which might include some leachate



solids such as ashes and certain soils.  Studies made in



Berkeley, California, in 1952 and repeated for the same area



in 1967 verify this conclusion and show that the percentages



of individual components changed very little over the 15-



year period.








Data on the amount and composition of industrial solid



wastes and its disposal are less extensive.  A survey



(Manufacturing Chemists Association, 1967)  of 991 chemical



plants, of which 889 were production facilities is reported



in Table 14.  It shows that 75 percent of waste solids were
                             153

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noncombustible process solids and that 71 percent of the

total was disposed of by landfill on company-owned property.

No data are at hand on the composition of these wastes but

it must be presumed that some fraction of the total was

leachable if conditions leading to leaching occurred.

Santa Los Louis-
Clara'1 Angeles^5 villec
Paper Products 50 41 60
Food Wastes 12 6 18
Garden Waste1- 9 21
Plastics 1 2
Cloth, Leather
Rags, Rubber 42 —
Wood 22-
Rocks, Dirt
Miscellaneous
Unclassified 7 12 3
Metals 869
Glass and
Ceramics 7 8 10
a. EPA, 1970; University of California
b. Bergman, 1972
c. EPA, 1970; University of Louisville
d. US Public Health Service, 1968
e. Bell, 1963
f. Niessen and Chanskey, 1970
Quad-
Cities Purdue 23 Madison National
N.J.d Univ.e Citiesf Wis.g Avg.
45 42 46 52 50
1 12 17 10 15
1 12 10 8 5
2 1 1 2 3J

5 2 4 4 2k
i 2 3 2


10 15 1 -- 7
98978

66 9 15 8
g. Ham, 1971
h. Salvato, et al, 1971
i. Total 3 categories « 23 percent
j. Includes rubber
k. Rubber included with plastics

         Table 13  Components of domestic solid
                   waste  (expressed as percentages
                   of total).
                             154

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Type of Waste
Process solids, non-combustible
Process solids, combustible
Containers, non-combustible
Containers, combustible
Fly ash from fuel combustion
Other, or unspecified

Disposal Method
Landfill on company property
Landfill away from company
property
Incineration, with heat recovery
Incineration, without heat recovery
Open dump burning
Contracted disposal
Other, or unspecified

Total Per Year
(Thousands of
Metric Tons)

7,624
520
58
152
1,440
423
10,217

7,318

472
83
210
99
1,476
559
10,217
Percent
Total

75
5
1
1
14
4


71

5
1
2
1
15
6

Table 14  Landfill disposal
          of chemical process wastes.
                    155

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Leaching^of^Lan dfillg



Leaching of landfills with consequent degradation of



underlying ground water depends upon several factors.



These, together with measures for control were summarized in



1971  (Salvato, et al, 1971).








If a  landfill   is to produce leachate there must be some



source of water iroving through the fill material.  Possible



sources include: (1) precipation,  (2) moisture content of



refuse, (3) surface water infiltrating into the fill,  (t)



percolating water entering the fill from adjacent land area,



or  (5) ground water in contact with the fill.  In any event,



leactiate is not produced in a landfill until at least  some



significant portion of the fill material reaches field



capacity.   To accomplish this U.ll cm of water per meter of



depth of fill is reported to be necessary.  This value is



far in excess of that which might be produced from a typical



mixed refuse.  Moisture in refuse is about 20 percent  by



weight.  Because of the high paper content and the



relatively inert material  shown in the typical analyses.



Table 13, only a small amount of moisture is released  by the



decomposition of the organic solids  in refuse.  A composite



sample of an average municipal refuse is shown in Table 15.
                             156

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   Moisture
   Cellulose, sugar, starch
   Lipids
   Protein - 6.25N
   Other organics
   Inerts
Percent

 20.73
 46.63
  4.50
  2.06
  1.15
 24.93

100.00
         Table  15  Composition of
                    municipal refuse
To induce composting,  a moisture content of 50 to 60 percent

is required,  hence a fill in a very arid region having no

source of moisture except that cf urban  refuse will

decompose very  slowly and produce little if any leaqhate.

On the other  hand, if a fill were made of fruits and

vegetables having 80 to 90 percent moisture, anaerobic

decomposition would proceed rapidly and  leachate would be

produced.  Thus,  landfill is not recommended for cannery

wastes alone.



Percolating water entering a landfill from surrounding land

is not likely in  a proper landfill.  If  other sources of
                             157

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water are excluded from a landfill by employing procedures



described in a later section, the production of leachate in



a well designed and managed landfill can be effectively



eliminated.  A proper landfill not intersecting the water



table will not cause water quality impairment for either



domestic or irrigation use.  Subsequent reports of test



borings around landfills dating back as far as 50 years in



England showed no evidence of ground water pollution as a



result of leaching.  Similarly, no evidence was found in



Holland that past landfilling has been a source of pollution



of ground water.  Evidence reported from Illinois and



Minnesota is that leaching did not contaminate ground water



in two major fills built within the aquifer itself.



Compaction of fill material, clogging of fill area walls and



balance of hydrostatic pressure cause ground water to flow



around the fill rather than through it.








Absence of leaching as an important problem is



characteristic of landfill  sites engineered and constructed



in accord with best current technology.  In this category



are most of the sanitary landfills comprising 8 percent of



the present land disposal situations, and presumably those



to be built in the future.  The 75 percent of urban refuse
                            158

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placed in dumps, which in varying degrees are open to



external sources of water, are likely to produce leachate in



significant amounts.  It is estimated that of 124 cm annual



rainfall in New York, 45 percent will infiltrate into an



unsealed and unprotected dump.  At some seasons of the year



up to 75 percent of the infiltrated water may be returned to



the atmosphere by evapotranspiration.  The remainder, and at



times all, cf the infiltrate will percolate through the



landfill.  If the fill is in a subsurface excavation, this



percolate will mcve downward to the ground water at a rate



governed by the degree of clogging of the underlying and



surrounding soil.  Clogging, however, may reduce



permeability at the infiltrative surface; it cannot be



assumed that the landfill will long discharge leachate at an



appreciable rate.  It may tend to become essentially a basin



filled with saturated refuse and soil.  Further rainfall



will then run off the fill surface without coming in contact



with refuse.  However, if leachate is produced within a fill



and soil clogging controls its escape to the ground water, a



large fill area, even at a low rate of movement into the



underlying strata, could with time, discharge a significant



volume of leachate.
                            159

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A secondary leaching phenomenon associated with all types of



landfills not subjected to specific controls is the result



of COz generated in the fill being forced outward into the



surrounding soil.  When picked up by percolating rain water,



this increases the aggressiveness of water to limestones and



dolomites and so increases the hardness of ground water.  A



refuse of the composition shown in Table 15 is theoretically



capable of producing 0.169 cubic meters of CO^ per kilogram



of refuse (Anderson and Callinan, 1969).  However, the



balance of nutrients, the moisture, and other environmental



factors are unlikely to exist over the time span necessary



for any such complete destruction of the carbonaceous



fraction of refuse.







Nature and Amount^cf Leachate



Data on the analysis of leachate vary widely.  Much of it



comes from short-term lysimeter studies in which researchers



had to make special effects to saturate the refuse so as to



produce maximum leaching.  Thereafter, experiments were



often terminated before the leaching rate reached an



equilibrium.  Data on leachate from several sources are



summarized in Table 16.
                             160

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Table 16 indicates what many observers have reported:  the



initial values of EOD and COD are always high.  Studies of



operating landfills show constituents of leachate to



include:



    COD            8,000 - 10,000 mg/1



    BOD            2,500 mg/1



    Iron           600 mg/1



    Chloride       250 mg/1








Table 16 also shows hardness, alkalinity, and some ions to




be significantly increased.  The California data also show



that continuous flew through one acre-foot of newly



deposited refuse might leach out during the first year



approximately:








         Sodium plus potassium    1.36 tons



         Calcium plus magnesium   0.9 tons



         Chloride                 0.83 tons



         Sulfate                  0.21 tons



         Bicarbonates             3.54 tons
                            161

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Determination (mg/£)

pH
Total hardness (CaCCb)
Iron total
Sodium
Potassium
Sulfate
Chloride
Nitrate
Alkalinity as CaCCb
Ammonia nitrogen
Organic nitrogen
COD
BOD
Total dissolved solids
a. No age of fill specified
5 is from 3-year old fill
b. Data from Los Angeles
c. Data from Emrich and

lb
5.6
8,120
305
1,805
1,860
630
2,240
no result
8,100
815
550
no result
32,400
no result
for Sources 1-3, Source 4
, 6 is from 15-year old fil
County (1968).
Landon(1969).

2b
5.9
3,260
336
350
655
1,220
no result
5
1,710
141
152
7,130
7,050
9,190
is initial



Sourcea
3b 4c
8.3
537
219 1,000
600
no result
99
300 2,000
18
1,290
no result
no result
no result 750,000
no result 720,000
2,000
leachate composition,




5C 6C

8,700 500



940 24
1,000 220






11,254 2,075




Table 16  Leachate composition
                             162

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Rates for subsequent years were expected to be greatly



reduced.








Field studies of the amount and quality of leachate through



well-designed fills have been made by the Los Angeles County



Sanitation Districts.  At their Mission Canyon Landfill,



underdrains were installed beneath two large fills to entrap



leachate.  One was installed in 1963; the other in 1968.  At



the time  of Meichtry's report (1971)  the first of these two



had produced nothing but odorous gases although the fill was



heavily irrigated from 1968 onward.  The second, deeper fill



produced  odorous gases but no leachate until March 1968 when



11 cm of  rain fell in 2U hours.   On that occasion 806.1



liters of leachate were collected.  Flow then continued at a



rate of about 5678 liters per month.   Periodic analysis of



the leachate indicated that a spring in the canyon wall



beneath the fill, rather than infiltration of the fill, was



the source.








Table 17  shows both the initial composition of the leachate



and its reduction with time over a 3-year period.  The Table



shows a decrease in concentration of most constituents of



the leachate with time.  This same phenomenon has been
                            163

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observed in comparing a 21-year old abandoned fill with an



active fill.







Pilot studies were made in 1964 to 1966 to study the effects



of rainfall and irrigation on landfill leaching.  Two cells,



15 meters square at the bottom and sloped to the top, were



filled with a single 5.3 meter lift of refuse, plus a 61 cm



earth cover.  Devices to collect leachate at various depths



were installed.   Cne was subjected to simulated rainfall,



the other to irrigation of turf.  After 27 months and 330 cm



of rainfall, no leachate appeared in the rainfall cell,  A.



small amount of water appeared in the topmost cell of the



irrigated system at 27 months and 429 cm of applied water.
                             164

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Constituent

PH
Total Solids, mg/£
Suspended Solids, mg/6
Dissolved Solids, mg/fi
Total Hardness, mg/C CaCO^
Calcium, mg/C CaCO^
Magnesium, mg/£ CaC03
Total Alkalinity, mg/£ CaCO3
Ammonia, mg/£ N
Organic Nitrogen, mg/£ N
BOD, mg/5 O
COD, mg/C O
Sulfate, mg/C 804
Total Phosphate, mg/£ PO4
Chloride, mg/8 Cl
Sodium, mg/£ Na
Potassium, mg/C K
Boron, mg/C B
Iron, mg/£ Fe
Leachate Analysis
Mission
3-18-68
5.75
45,070
172
44,900
22,800
7,200
15,600
9,680
0.0
104
10,900
76,800
1,190
0.24
660
767
68
1.49
2,820
Canyon Landfill
3-24-71
7.40
13,629
220
13,409
8,930
216
8,714
8,677
270
92.4
908
3,042
19
0.65
2,355
1,160
440
3.76
4.75
Table 17  Change in leachate
          analysis with time  (Meichtry, 1971)
                   165

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Limited experiments, such as the foregoing, support the



conclusion previously cited that leachate from well-designed



fills is not a significant problem.







The time required to produce leachate from a fill penetrated



by rainfall can be predicted by moisture-routing techniques



(Remson, 1968).  For example, a 2.U4 meter lift of refuse



with 61 cm of earth cover will take from 1 to 2 1/2 years to



reach field capacity and produce leachate if 117.8 cm of



rainfall is allowed to infiltrate and percolate into the



fill.







In one field observation (Hassan, 1971) a landfill partly



inundated by ground water was investigated.  Well water 325



meters down gradient from the fill showed leachate effects



in terms of hardness, alkalinity, Ca, Mg, Na, K, and Cl.  At



a distance of 1,000 meters the effects were undetectable.



Inasmuch as the fill was an old one, it might be concluded



that the ground water was not seriously affected.  However,



similar studies in Germany revealed the presence of leachate



effects in ground water 3,000 meters away.
                             166

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In the case of industrial wastes disposed of by landfill on



company property, little is known of the nature and extent



of leachate.  Table 14 shows that noncombustible solids



represent 75 percent and ashes another 1U percent of the



total.  These data suggest that soluble minerals provide the



most common materials which might be leached from industrial



waste fills.  In terms of ground water pollution, oil,



process sludges, and salt solutions from lagoons and pits



are likely to be the most significant industrial wastes.








Control^Methgds




In general, procedures for the control of leachate are those



which exclude water from the landfill, prevent leachate from



percolating to ground water, or collect leachate and subject




it to biological treatment.  Obviously, the possible



utilization of these three approaches is maximum in the



design phase of a landfill operation and minimal in some



types of existing landfills.








In existing situations the potential of a landfill to



pollute ground water can be limited by such procedures as:



    •    separating at the source wastes which are



         unacceptable in a given landfill situation.
                            167

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    •    Controlling haulers by requiring permits and by



         enforcing restrictions on materials for disposal,



    •    Licensing private haulers of industrial wastes.







In the case of a new projected landfill the control measures



include:



    •    Select site to achieve both general regulations and



         specific objectives.   Typical of the general



         measures for siting control are those of Los



         Angeles County which recognize three classes of



         fills:



              Class I, which may accept all types of solid



              wastes by reason of its geologic isolation



              from any contact with the ground water.  This



              type of site is essentially an impervious



              bowl, and hence is not common.



         "    Class II, which may accept the normal run of



              mixed municipal solid refuse  (no waste oils,



              or chemical sludges) .



         -    Class III, which may accept only inert earth-



              type materials.
                             168

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Specific siting involves evaluation of alternate



locations by hydrogeologists and engineers to



determine such things as:



-    Location and depth of ground water in the



     vicinity.



     Importance of underlying ground water as a



     resource, both present and future.



     Nature of geology of the site.



     Feasibility of excluding both surface water



     and ground water from the finished fill.








Design landfill to correct deficiencies of best



available site:



     Use compacted earth fill to seal walls and



     bottom of fill site.  If the fill is above



     water table, as is most commonly required,



     this will minimize the rate of escape of



     leachate from the fill.  If the fill is in an



     aquifer, the movement of the ground water into



     and out of the fill will be minimized.



     Provide underdrainage system to collect



     leachate and deliver it to a sump.
                    169

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     Drain sump to surface by a valved pipe or by a



     vertical well into which a submersible pump



     may be inserted, if necessary, to collect and



     deliver leachate for biological treatment.







Construct fill with purpose of keeping the minimum



of refuse surface exposed to rainfall, and the



working surface and site well drained.  Use dike



and fill technique to isolate fill from unfilled



area.







Utilize water for dust control during construction



in such amounts that evaporation rather than



infiltration is its fate.







Divert surface water from the fill site during and



after fill construction by means of peripheral



bypass drains.







Compact and slope fill cover for good surface



drainage, vent gases through the fill cover with J-



vents.
                    170

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In new or existing landfills:



•    Provide continuing maintenance of the graded



     finished fill cover,  fill in and regrade surface as



     shrinkage of the fill causes cracks or depressions



     which might serve to increase infiltration.



•    Seed completed fill surface with a high



     transpiration cover crop.



•    Avoid over irrigation of  surface plantings.



•    Divert both surface and ground water around fill



     site where feasible.



•    Reduce the amount of putrescible solid waste by



     initiating regional reclamation activities under a



     statewide authority which features energy



     conversion of the organic fraction of refuse.







In the case cf existing landfills and dumps:



•    Intercept polluted ground water at the fill site by



     well points in or near the fill area if the



     situation is serious.



•    Initiate and implement statewide programs of waste



     management which feature  regional landfills, thus



     replacing numerous small  refuse dumps with
                        171

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         landfills en an economic scale, phasing out with



         time the leachate contribution to ground water.








Of the foregoing control measures only those which are



applicable to new sanitary landfills have the potential to



prevent or essentially to eliminate the possibility of



ground water pollution by leachate.  Siting, constructing,



operating, and maintaining fills are in this category of



control measures.  Existing well-engineered landfills,



although not generally equipped with underdrains, are



minimal in their effects upon ground water quality and hence



of secondary importance in comparison with dumps.  Similarly,



old landfills may have contributed the major portion of



their leachate already and are now of secondary importance.



Reshaping the soil surface and maintaining surface drainage



are measures which reduce the effect of leachate from



existing fills.  The overall effect of dumps may be lessened



by a geographical distribution of the volume of wastes they



contain.  Control measures such as well-point interception



reduce rather than prevent or eliminate leachate discharges.



Regionalization of waste treatment is a control measure



which can reduce and eventually phase out the leachate from



existing dumps.
                             172

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Monitoring Procedures
In new fills,  properly engineered and sealed off from
underlying and sidewall strata, the drainage system and a
pumped well located in or near the fill can be used both for
inspection (monitoring)  and for control.

A system of three observation wells is illustrated in Table
18 along with the results of ground water quality
observations.
Groundwater
Characteristics
Total Dissolved
Solids
pH
COD
Total Hardness
Sodium
Chloride
Background
(mg/liter)

636
7.2
20
570
30
18
Fill
(mg/liter)

6712
6.7
1863
4960
806
1710
Monitor Well
(mg/liter)

1506
7.3
71
820
316
248
         Table 18  Ground water quality
                            173

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It would be feasible to drill and gravel pack a sampling



well in a landfill, then seal its bottom and drill through



to the ground water below.  Portable submersible pumps could



be used to pump these two essentially concentric wells for



sampling purposes.  An alternative might be to drill a



pumped monitoring well downstream from the landfill or



directly through the fill.  Concentrations of TDS, hardness,



and chlorides could be measured and used to surmise the



presence of leachate, provided the discharge rate needed to



produce a significant drawdown cone under the fill did not



obscure the effect of leachate on the ground water quality.



In any event the best procedure is the use of control



measures which minimize the possibility of leaching of



landfills.
                             174

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References

1.  Anderson, D.R., and Callinan, J.P., Gas Generation and
    Movement in Landfills, paper  (1969) .

2.  Anon. , "Sanitary Landfills: The Latest Thinking," Civil
    Ingineer. ing , Vcl. 43, No. 3, pp 69-71  (1973) .
3.  Bergman, R.D., "Urgent Need to Recycle Solid Wastes?,"
    Civil Engineering, Vol. 42, No. 9  (1972).

4.  Bell, J.M., "Characteristics of Municipal Refuse,"
                of ttotional Conference OQ Solj.d Wastes
              American Public Works Association Research
    Foundation, Chicago  (1963) .

5.  Burch, L. A. , "Solid Waste Disposal and Its Effect on
    Water Quality", Vector View^, Vol. 16, No. 11  (1969).

6.  California State Water Pollution Board, Report on.
    iGY^stigation 2£ I^SShi23 2% a SaniiSO Landfill,
    Publication No. 10, Sacramento, California  (1954) .

7.  Dall, Frank R. , "The Effect of Solid Waste Landfills on
    Groundwater Quality," Sixth Biennial Conference on
    SESuncl Water Recharge^ Development Management,
    University of California, Berkeley (1967) . """

8.  Emrich, G.H,, and Landon, R.A., "Generation of Leachate
    from Landfills and Its Subsurface Movement," Annual
    Northeastern Regional An ti.- Pollution Conference
    University of Bhode Island, Kingston  (1969) .
                                                    ,
9.  Environmental Protection Agency, "A Citizen's Solid
    Waste Management Project", Mission 5000, EPA  (1972)
                            175

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10. Environmental Protection Agency, Cpmprehensive Studies
    2£ Solid Waste Managementx First and second Annual
    gepgrt§7 U.S. Public Public Health Service, Publication
    No. 2039, Research Grant EC-00260, University of
    California (1970).

11. Environmental Protection Agency, Solid Wastes Disposal
    S&idv.' YQi- Ir J§fJj£Spn County., Kentucky; Institute of
    Industrial Research,, University of Louisville, U.S.
    Department of Health, Education, and Welfare, Bureau of
    Solid Waste Management  (1970).

12. Golueke, C.G., and McGauhey, P.H., Comprehensive Studies
    of Solid Waste Management, First Annual Report7~SERL
    Report No. 67-7, Sanitary Engineering Research
    Laboratory, University of California, (Berkeley 1967).

13. Ham, R.K., personal communication. University of
    Wisconsin  (1971).

14. Hassan, A.A., "Effects of Sanitary Landfills on Quality
    of Groundwater — General Background and Current Study,"
    Paper presented at Los Angeles Forum on Solid Waste
    Management (1971) .

15. Hughes, G.M., et alr Hy.drogeoloc[y. of Solid Waste
    Disposal Sites in Northeastern Illinois, Progjrejfs Regprt
    DQirQQOOj6, UjS. Department of Health, Education, and
    Welfare  (1968) .

16. Kaiser, E.R., "Chem-ical Analysis of Refuse Components,"
    Ergceedings 1266 Incinjeratqr Conference, American
    Society of Mechanical Engineers, New York, New York
    (1966) .
                             176

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17. Los Angeles County, Development of Construction on Usg
    Criteria for Sanitary Landfills, USPHS~Grant~No.^DOl-Ul-
    00046, County^of Los Angeles, California (1968).

18, Manufacturing Chemists Association, "Most Solid Wastes
    from Chemical Processes Used as Landfill on Company
    Property," Currents (1967).

19. Meichtry, T.M., "Leachate Control Systems," Paper
    presented at Los Ancjeles Forum on Solid Waste Management
    (1971) .

20. Merz, R.C., and Stone, R.r Progress Report on Study of
    Percolation Through a Landfall, USPHS Research Grant SW
    00028-07 (1967) .

21. McGauhey, P.H., and Krone, R.B. , Soil Mantle as a
    Wastewater Treatment System, Final Report,  SERL Report
    No. 67-11, Sanitary Engineering Research Laboratory,
    University of California, Berkely  (1967).

22. McGauhey, P.H., and Winneberger, J.H., Causes and
    Prevention of Failure of Septic^Tank Percolation"
    Systems, Tech. Studies Report, FHA No. 533", Federal
    Housing Administration, Washington, D.C. (1964).

23. LeGrand, H.E., "Systems for Evaluation of Contamination
    Potential of Solid Waste Disposal Sites", American
    Waterworks Association Journal,  Vol.56,  pp 959-974
   (1964).
                            177

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SEWER LEAKAGE
Gravity sewers above the ground water table, and pressure



outfalls either above or below it, are common elements of the



domestic sewerage system of organized communities.



Seasonally, storm sewers involving underground conduits and



lined and unlined open channels carry runoff from paved and



unpaved land surfaces.  Essentially all of these conduits



are sited to accomplish drainage objectives.







Many major sewer systems had their beginnings at least a



century ago and soire original sectors of these systems are



still in use.  Over this long period, construction materials



and methods have changed profoundly as the total length of



sewers has grown to tens of thousands of kilometers.  Joints



in many of the gravity sewer systems carrying domestic



sewage number from 621 to 1243 per kilometer.  Joining



materials have ranged through the years from cement mortar



to asphaltic and similar special compounds, and to plastic O-



rings and heat- shrinkage joint covers.
                             178

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Causal Factors



The potential of a municipal sewage system to contaminate



ground water is both varied and variable.  Conceptually, a



sewer is intended to be water-tight and thus to present no



hazard to ground water except when temporarily disrupted by



accident.  In reality, however, leakage is a common



occurrence, especially from older sewers.  Leakage in



gravity sewers may result from causes such as:







    •    Poor workmanship, especially at the time mortar was



         applied by hand as a joining material,



    •    Cracked or defective pipe sections incorporated in



         the sewer,



    •    Breakage of pipe and joining material by tree roots



         penetrating or heaving the sewer line,



    •    Displacement or rupture of pipeline by superimposed



         loads, heavy equipment, or earthfill on pipe laid



         on a pocr foundation,



    •    Rupture of pipe joints or pipe sections by slippage



         of soil in hilly topography,



    •    Fracture and displacement of pipe by seismic



         activity; e.g., a sewerage system in California,
                             179

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         still suffers from fractures caused by an



         earthquake in 1909,



    •    Loss of foundation support due to underground



         washout,



    •    Poorly constructed manholes or shearing of pipe at



         manholes due to differential settlement,



    •    Infiltration surcharging the system and causing



         sewage to back up into abandoned sewer laterals.








Environmental consequences



Except at times of heavy infiltration during storms, which



may surcharge a system, the piezcmetric pressure inside a



gravity sewer laid above ground water is small.  The static



head may vary from a maximum equal to the pipe diameter to a



minimum of perhaps 20 percent of that diameter.



Consequently, the rate of leakage accompanying several of



the cited failures is quite small.  In fact, some small



leaks become stopped through closing of the opening by



suspended solids.  Major fractures may release an



appreciable amount of sewage which moves along the pipe




foundation as the soil clogs, causing the trench locally to



function like the percolation system of a septic tank.
                             180

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Material escaping from a sewer via leakage is raw sewage,



which may be actively decomposing, together with such



industrial waste chemicals as may be present in the sewer.



Thus, if a sewer is deep underground and close to the ground



water, pollutants may be released below the biologically



active zone of the soil and so introduce into the receiving



ground water BOD and COD as well as chlorides and unstable



organics productive of tastes and odors.  Because this



tendency is partly offset by the clogging of soils under



anaerobic conditions, the true effect of sewer leakage on



ground water quality is probably far less than the



theoretical potential.







If a fractured sewer is below the water table, infiltration



rather than leakage is the result.  If infiltration is



seasonal and leakage occurs part of the year, the effect of



the intermittent flow may be to unclog the system and so



maintain a higher seasonal leakage rate than that of year-



round leakage.







Pressured outfall sewers are normally made of cast iron,



steel, transite, or concrete pipe.  Except in very large



diameters they have fewer joints per mile than gravity
                            181

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sewers,  and the joining is less likely to be of poor quality



or so readily ruptured.  Because of superior construction



and engineering attention, the outfall sewer is not often a



threat to ground water quality.  Due to the internal



pressure when leakage does occur, it is normally outward



regardless of whether the pipe is above or below the water



table.  Small openings may clog,but most commonly sewage is



injected into soil cr ground water directly.  It may appear



on the surface of the soil or outcrop on a hillside where it



is easily detected by sight and odor.








The effect of storm drains is generally to hasten the flow



of surface water to a surface stream.  Therefore, it is



likely to have less potential than uncontrolled surface



runoff to spread the oils and soluble matter from streets,



fertilized land, and pesticide-treated gardens over



infiltrative surfaces feeding the ground water.








Looking to the future, it seems certain that sewer leakage



will be less of a hazard to ground water than at present,




even though the extent of sewer systems is certain to



increase to accommodate the growth and urbanization of
                             182

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population.  The principal reasons are improved construction



and maintenance practices:








    •    Both new sewers and replaced old lines are laid



         with joining materials which are water-tight and



         also permit some change in pipe alignment without



         fracturing.



    •    Better construction methods are practiced by



         contractors.



    •    More rigid specifications and better inspection



         characterize the larger units of government now



         responsible for sewerage.



    •    Equipment for photographing or televising the



         interior of a pipeline is available and



         increasingly used to locate leaks and fractures in



         a sewer system,



    •    Muncipal public works departments, using their own



         personal or private contractors, are increasingly



         and systematically surveying the condition of



         sewers within their jurisdictions in a "search and



         destroy" program of sewer repair and maintenance.



    •    Sewer maintenance has become a special division of



         public works departments, and both the Water
                             183

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         Pollution Control Federation and its member



         societies conduct annual short courses and training



         programs in the technology of maintaining sewers.







Control_Met.hods



Procedures for controlling the potential of sewer leakage to



degrade ground waters are implicit in the improved practices



listed above.  The sewerage system of a large community is



an infinite point system of possible leaks.  Moreover, the



system is underground and hence not subject to control by



surface observation and repair.  Therefore, the most



productive control program has the following features:



    •    A public policy of maximum protection of ground



         water as a part of an overall concern for resource



         conservation,



    •    An organized and identified responsibility for



         sewer construction and maintenance in the community,,



    •    Formulation and modernization of codes and



         specifications for sewer construction as a state,



         rather than a city responsibility, together with



         appropriate inspection procedures,



    •    A program of internal and external inspection of



         existing sewers at five-year intervals to detect
                             184

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         and repair major leaks or to replace unrepairable



         sectors of the sewer system,



    •    Emphasis en training of sewer maintenance personnel,



    •    Exclusion from discharge to municipal sewers of any



         materials found to be irretrievably hazardous to



         ground water.








Monitoring^Procedures



As in the case of lagoons, basins, and pits, monitoring of



ground water quality in relation to sewer leakage is best



accomplished by a program of collection and evaluation of



ground water data in each metropolitan area.  Similarly,



surveillance of the control procedures should be maintained



so as to prevent and to correct leakage.
                            185

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TANK AND PIPELINE LEAKAGE







Scope of thgt Problem



In the United States, underground storage and transmission of



a wide variety of fuels and chemicals is a common practice



for commercial, industrial, and individual uses.



Unfortunately, the pipes and tanks are subject to failures



from a wide variety of causes and the subsequent leakage



then becomes a source of contamination to local ground



waters.  European countries also have experienced these



problems; their technical literature is well worth



consulting.







This section describes the nature and occurrence of tank and



pipeline leakage and summarizes the practices that have been



found effective in the control and abatement of ground water



pollution.  Emphasis in this section is on petroleum



products because they constitute the majority of materials



stored or transmitted in subsurface excavations.  Leakage of



petroleum and petroleum products from underground pipelines



and tanks may be much more pervasive than is generally



realized.  This is particularly true for small installations



such as home fuel oil tanks and gasoline stations, where
                             186

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installation, inspection, and maintenance standards may be



low.  In Maryland, where standardized investigative



procedures have been adopted, some 60 instances of ground



water pollution were reported in a single year from gasoline



stations.  In northern Europe, where most homes are heated



by oil stored in subsurface tanks, oil pollution has become



a major threat tc ground water quality (Todd, 1973).








Radioactive_Wastes



Tanks of solid radioactive wastes often are buried in



underground pits, primarily as a means of storing them in a



shielding medium while the radioactivity decays.  Five sites



for storing low-level wastes are used in the United States,



operating under license and regulated by the states in which



they are located: Pichland, Washington; Beatty, Nevada;



Sheffield, Illinois; West Valley, New York; and Morehead,



Kentucky.  Under state regulations, the sites are designed



and operated so that no leakage should occur.  To assure



that no leakage is occurring, the states require and perform



monitoring of surface water and ground water in the vicinity



of the sites as well as from sumps in the backfilled pits.



The high-level wastes are under Federal control and there
                            187

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has been some leakage from such facilities.   The EPA is



reviewing both types of storage at this time.








History



In the United States the use of underground tanks and pipes



has been most heavy in the petroleum industry.   Here their



use has expanded with the industry to the point where



pipelines are now the major mode of transportation for



liquids and gases within the continental United States.  The



present and increasing emphasis on the aesthetic value of



burying utilities and other commercial or industrial



structures will undoubtedly increase the number of tanks and



pipes that will be placed in excavations.  Because pipelines



are an economical means of shipping, there is an increasing



trend toward developing methods for pipelining solids such



as coal or ores by powdering the solids and mixing them with



water or oil to produce a pumpable slurry.








Leakage in the United Statgs



Underground storage tanks are used in the United States by



industries, by commercial establishments, and by individual



residences.  Industrial use is predominantly for fuels, but



a wide range of ether chemicals are also stored in tanks.
                            188

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Commercial businesses and individual homeowners use



underground storage almost exclusively for fuel.  The most



numerous underground storage tanks are those used by



gasoline stations and for fuel oil at residences.  These



small tanks are usually coated with a protective paint or



corrosion resistant material, but they are frequently



subject to corrosion-induced leakage.  The primary problem



associated with such tanks is the fact that their



installation and use are not usually well regulated.  If any



regulation exists concerning such tanks, in most cases it is



a local regulation requiring that tank construction and



installation be satisfactory, but it is rare that any



follow-up or periodic checks are required to determine



whether or not leaks have developed.  Because such tanks are



small and comparativley inexpensive, cathodic protection is



not required even when the tanks are buried in clay soils,



which are known to promote galvanic action.
Pipelines are used for transportation, for collection, and



for distribution.  Transportation pipelines are used for a



wide number of chemicals including oil, gasr ammonia, coal,



and sulfur.  Their heaviest use is for the transportation of
                            189

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petroleum products, natural gas, and waterr in that order.



The list of commodities lost by accidents during one year



from liquid interstate pipelines is shown in Table 19.








Many industries employ underground collection pipelines to



move process fluids and wastes in-plant or for storage or



shipment.  In oil fields, collection pipelines are used to



bring crude oil from wells to tanks for separation of



brines, and for storage and shipment.








The only pipelines for which any program of leak prevention



and any requirements for decontamination exist are the



transportation pipelines, and all of these are not covered.



All interstate transportation pipelines and some intrastate



pipelines are regulated; on collection and distribution



pipelines there is no regulation other than that of the



initial installation.  The purpose and intent of the



regulations that exist are for preventing the escape of



combustible, explosive, or toxic chemicals.  Prevention of



ground water pollution has not heretofore been the primary



consideration.  Because interstate piplines are a major



means of transportation, they are regulated by Federal



government agencies in the Department of Transportation.
                             190

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Because leaks of petroleum products can produce a fire or



explosion hazard, these regulated pipelines have been



required, for the past five years, to report leaks and



spills.  An analysis of these reports has been made and is



summarized in Table 20.  It should be noted that the



quantities reported represent only leakage associated with



interstate carrier systems.  This means that local



collection and distribution systems, gas stations,



residential users, and even relatively large intrastate



carriers are not included.  Therefore, it must be assumed



that the leakage reported covers considerably less than 100



percent of the total leakage in the country.








Environmental Consequences



Pipeline and tank leakage into the soil can have several



environmental consequences, depending upon the chemical



leaked.  Oils and petroleum products in even trace



quantities will render potable water objectionable because



of taste, odor, and effects on vegetation.








In sufficiently high concentrations,the vapors of lighter



fractions of petroleum products, liquified petroleum gas,



and natural gas can seep into basements, excavations.
                             191

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tunnels, and other underground structures.  These vapors

mixed with the air in the cavity constitute a severe

explosion or fire hazard in the presence of open flame or

sparks.

Commodity
Crude Oil
Gasoline
L. P. G.
Fuel Oil
Diesel Fuel
Condensate
Jet Fuel
Natural Gasoline
Anhydrous Ammonia
Kerosene
Alkylate
Total
No. of
Accidents
172
51
39
21
5
5
4
4
3
2
2
308
%of
Total
55.9
16.6
12.7
6.8
1.6
1.6
1.3
1.3
1.0
.6
.6
100.0
Loss
(kiloliters)
18,404
6,677
6,341
2,102
1,105
582
355
1,390
1,560
111
252
245,057
%of
Total
47.2
17.1
16.3
5.6
2.8
1.5
.9
3.6
4.0
.3
.7
100.0
         Table 19   Summary of interstate liquid pipeline
                    accidents for 1971  (Office of Pipeline
                    Safety, 1972).
                             192

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      Number of accidents - 300 to 500


      Number of tons lost —  33,333 to 66,666

      Value of property damage - $650,000 to $1,300,000


      Number of deaths - 1 to 11

      Number of injuries — 8 to 32

      Major cause — Corrosion

      Major commodity lost — Crude oil
Table 20   Range  of annual pipeline  leak  losses
            reported on  DOT Form 7000-1 for the
            period 1968  through 1971.
                       193

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Chemicals such as ammonia and other agricultural or



industrial chemicals can have toxic properties.  For



example, ammonia will add to the nitrification of ground



water, while acids can change the pH of ground water which,



in turn, will accelerate the solution of soil solids and



heavy metals.







The leakage of water can produce undesirable effects if the



dissolved solids in the water introduce objectionable



hardness or if the water is a brine.







Causal Factors



The annual report of leakage of interstate pipelines appears



to be representative of the cause of leaks for all pipelines



and tanks.  Table 21 is extracted from Office of Pipeline



Satety  (1972) to show the relative frequency of causes.



Other causes that have been reported in other years but did



not occur in 1971 were floods and surges of fluid in the



pipeline.  Examination of the Table indicates that the major



cause of leakage is corrosion, which attacks the lines both



externally and internally.  The second greatest cause can be



found by aggregating those related to pipeline component,



equipment, personnel failure, or malfunction.  The third
                             194

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greatest cause is line rupture as the result of accidents

caused by earth moving equipment.  The remaining few causes

include vandalism (usually bullet holes in exposed sections

of pipe, tanks or valves), severe weather, lightning, floods,

earthquakes and forest fires.
Cause
Corrosio n-ex ternal
Equipment rupturing line
Defective pipe seam
Corrosion-internal
Incorrect operation by carrier personnel
Miscellaneous
Ruptured or leaking gasket
Ruptured or leaking seal
Defective repair weld
Unknown
Ruptured leaking or malfunction of valve
Rupture of previously damaged pipe
Malfunction of control or relief equipment
Cold weather
Defective girth weld
Threads stripped or broken
Pump packing failure
Vandalism
Lightning
Total
Number
102
67
31
22
22
12
7
6
6
6
5
4
3
3
3
3
2
2
2
308
Percent
33.1
21.8
10.1
7.1
7.1
3.8
2.3
2.0
2.0
2.0
1.6
1.3
1.0
1.0
1.0
1.0
0.6
0.6
0.6
100.0
         Table 21  Frequency of causes of pipeline  leaks
                   in 1971  (Office of Pipeline Safety, 1972)
                             195

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Pollution Movernent



Liquid leaked into an underground excavation can behave in



several ways, depending on the characteristics of the soil



and the depth below the leak of the saturated zone.  The



statements below apply not only to oil but also to all



liquid pollutants emanating from underground tanks and



pipelines.  If the leak is from a tank of limited horizontal



extent or from a pipeline in relatively permeable soil, the



liquid will remain in the vicinity of the leak and move



downward through the soil under the influence of gravity.



On the other hand, if the leak is from a pipeline in



relatively impermeable soil, the leak liquid will tend to



remain in the trench.  In a sloping trench in impermeable



soil, the fluid will tend to move through the backfill in



the trench along the outside of the pipe in the direction of



the slope.  As liquid moves downward through the soil under



the influence of gravity, it will coat the soil particles as



it advances.  This process removes some liquid from the



downward moving material.  If the quantity of liquid is



small enough, it may be immobilized by this process,'



however, the leaked liquid may not remain immobilized.



Subsequent rainfall may wash the pollutant from the soil
                             196

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particles and carry it further downward until it reaches the



saturated zone.








If the leakage is large enough to reach the saturated zone



before exhaustion, its path of movement will depend upon the



density and viscosity of the fluid and whether it is



miscible with water.  Miscible liquids will dilute slowly



with distance and time.  Subsequent rainfall will tend to



displace oil or ether low density fluids floating on the



water table, producing a contaminated mixture in the upper



part of the aquifer.  Once in the saturated zone, a



pollutant will move downgradient.
Figure E shows a plan view of an actual situation involving



a large gasoline spill and indicates how the leakage is



apparently concentrated in a depression in the water table



created by pumping wells.








It is quite possible for leaked liquids to move laterally



for great distances above the saturated zone.  If a spill is



large enough,  or if a leak continues long enough, the fluid



can migrate along impermeable layers above the water table
                            197

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and the same can happen along a pipeline, as described



earlier, until it reaches a permeable region where it can



move downward.








It should be noted that most chemicals do not move with the



velocity of ground water.  Because of the effects of



sorption, varying iriscibility, solubility in water, and



varying chemical activity in the soils, chemicals usually



migrate through the soil in the direction of the ground



water flow but at a slower rate  (Committee on Environmental



Affairs, 1972).








Contrgl^Methods



Most of the research and development on methods for



controlling and abating the contamination of ground water by



leakage from tanks and pipelines in underground excavations



has been concerned with reducing fire, explosion, and



toxicity hazards.  Although it would appear that this work



is not often aimed toward abating pollution of ground water,



it may be applicable if judiciously applied.  Many described



methods for handling hazardous materials can also be applied



to handling leakage materials such as sewage, brines, and
                             198

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agricultural and  industrial chemicals net consic

hazardous.
                      STRONG TASTE
                      AND ODOR AREA
                         TEETx 100
                        PUMPING WELL
                        OBSERVATION WELL
         Figure E  Area contaminated by  subsurface gasoline
                    leakage and ground water contours in the
                    vicinity of Forest Lawn  Cemetery, Los Angeles
                    County, as of 1971  (Williams and Wilder,
                    1971).
                              199

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Prevention.  Primary control methods emphasize three types



of leak prevention:








    1)    Corrosion-preventing coatings such as tar or



         plastic used on the outside of tanks and pipelines,








    2)    Cathodic protection used to minimize corrosion




         resulting from galvanic action (Dept. of



         Transportation, 1969, 1970a),








    3)    Internal fiberglass linings,  which do not



         deteriorate, used for small tanks such as those



         used for gasoline storage  (Matis, 1971).








Containment.  Storage sites can be designed to contain



leaked liquids so that they can be trapped and removed



before they get into the soil.  These methods are almost



exclusively applied to tanks.  Lined excavations are



sometimes used to enclose a subsurface tank with an



impermeable material such as clay, tar, or sealed concrete.



These are analogous to the dikes used for containment in



oil-tank farms.
                             200

-------
Another method has been used in Switzerland (Todd, 1973) for



containing liquids that are lighter than water, such as oil.



An underground dam is built around the tank.  The dam is



designed to penetrate the water table to such a depth that



the full volume cf the tank could leak into the space inside



the dam, and the bottom of the pool of leaked fluid would be



well above the bottom of the dam.








In pipelines, containment can be accomplished by use of



automatic shutoff valves inserted in the pipe at intervals.



These valves are designed to close off any section of pipe



where a significant drop in line pressure occurs.  This



method, like containment devices for tanks, tends to limit



the spread and the volume of the leak and thereby permit



easier cleanup.  At the present time this form of protection



is required on interstate pipelines but not on most small



collection and distribution systems.








Abatement by removal of soil.  If a leak is discovered and



is accessible soon after it occurs, perhaps the best method



for preventing ground water contamination is removal of the



contaminated soil.  It is important that this method be



applied before rainfall occurs in the region.   Normally,
                             201

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without the flushing action of rainfall, liquids move



downward very slowly.








Figure F indicates that from several hours to a day or more



may be available before leaked liquids reach depths beyond



those that would be reasonable for normal earth removal.



This slow migration downward is a characteristic not only of



leaks small enough that they will be exhausted to immobility



before they reach the saturated zone,but also of leaks large



enough to eventually reach the saturated zone.  Thus, in



dealing with the large leaks that are associated with a



catastrophic failure, such as a tank or pipe rupture, it is



important to initiate cleanup procedures rapidly.
                            202

-------
                       OIL SATURATION IN %
g
z
I—H
ffi
£
CD
Q
          1 -
          2 M
          3-
          6 —
          7-J
                   10
                   I
20
 I
30
 I
                                    40
                                INITIAL
                    , 10 HOURS
                L/
                  23 HOURS
         S(0)  =  50 %
         S(10) =  8,5%
         S(23) =  6,1%
         S(72) =  4, 6%
                 • 72 HOURS
  50
d -
d =


d =
                 0,59m
                 3,45m
                 4,80m
                 6,40m
Figure F  Experimental results from Switzerland  on the
           distribution of  oil in  soil as  a  function
           of  time  (Toddr 1973).
                            203

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After the soil has been removed, the problem of how to



dispose of it must be addressed.  The most suitable method



for handling biodegradable materials, such as oil, and many



agricultural chemicals such as ammonia, is to spread the



contaminated soil in a thin layer, 20 centimeters or less in



thickness, and permit the natural aerobic soil bacteria to



degrade it.  This is usually accomplished within six months.



If the liquid is not biodegradable, the soil must be removed



to an appropriate industrial waste treatment plant and



processed as an industrial waste.








It should be noted that earth removal can be an extensive



operation requiring more than simply digging a hole with a



bulldozer and hauling the soil away in a truck.  In at least



one case in an urban area, such earth removal involved the



demolishing of buildings and excavation of an area of



approximately the size of a city block.








Abatement by pumping or ditching.  In cases where the



pollutant has reached the water table but has not yet moved



a significant distance from the leakage site, a removal well



can be used.  This method works best for water-soluble



chemicals and for materials that float on the water table;
                             204

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however, it can be expensive and time consuming.  With



respect to soluble chemicals, the effect of pumping will be



to reverse the normal direction of movement away from the



site of the leak.  With respect to oil, the drawdown cone



that the well produces will trap the oil.  In the case of



oil, two pumping locations are often used—a deep pump inlet



to maintain the drawdown cone and a skimming pump with its



inlet floating on the surface to remove the oil (Figure G).







If the pollutant has moved so far downgradient that



recapture by use of a drawdown cone is infeasible, a ditch



placed across a shallow contaminated plume can be used to



capture the pollutant.  Figures H and I illustrate this



method.







When the water table is far below the surface of the ground,



a row of pumping wells may be required.  Placed across the



contaminated plume, their drawdown cones will merge,



producing a trench in the water table.  The contaminant



cannot escape from the depression and with time will



gradually be removed by the wells.  After the contaminated



water is removed, it must be processed as an industrial



wastewater before disposal to a sewage system or return to
                            205

-------
the aquifer.   The appropriate technique will depend upon  the


nature of  the  pollutant and upon  available wastewater



treatment  facilities.
       >V? "oo^c?" o_'_ °re° fp n ^^l*g!c
=>i.. ~ ^ _« c^ &r?.a o o,

        Perforated Casing ^^
           Figure G  Swedish  two-pump method for

                     removal  of oil pollution from

                     a well  (Todd, 1973).
                               206

-------
           Spill Area
Impermeable
 Barrier
^•••••v--ff«-4qaa

WateFJ.ffe;&:-:.^^^

'•"&•:'•••:•:'• JU^V'-'-v'-v"/'' .'.V-:-:-::-')Y-aler Movement :,i^^^.\;:V.y;V;'.^
                        Cross Section

 Figure  H  Oil moving with  shallow ground water
             is intercepted by a ditch constructed
             across  migration path  (Comm.  on
             Environmental Affairs,  1972).


                                                Al
                                              Line Of Section
                                                 Fig.2-B
          Water Movement
                         Plan View

                        207

-------
 Support
    Rod
    U
!
  To Suction
                                Power
                                Supply
         $m&y®
                          Support
                          Cable
Discharge
Line
                                        B   Submersible
                                           Electric Pump
           A Flotation Device May Be Substituted
           For The Handling Cable Or Rod.
Figure I  Three systems for  skimming oil from
           a water  surface  in ditches or wells
            (Comm. on  Environmental Affairs,  1972)
                      208

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Abatement by biodegradation.  A method currently under



investigation is that of subsurface biodegradation.  Many



chemicals such as ammonia and petroleum products are



biodegradable by aerobic bacteria, but below the surface air



transfer is slow and the aerobic bacteria tend to consume



the oxygen.  At the present time research is being conducted



to identify anaerobic bacteria that would also be capable of



such biodegradation.








Abatement by chemical action.  The use of chemicals to cause



precipitation of pcllutants within the soil is being



investigated.  Sc far as is known no experimental results



are available.  Further research on such methods is



required.








Monitoring Procedureg



In general the mcnitoring required for the detection of



leaks from tanks and pipelines in excavations is



proportional to the quantity of chemicals handled.








In small installations such as the household fuel storage



tank, gasoline station storage tank, and local collection or



distribution system, local monitoring is probably not
                            209

-------
economically feasible.  If local governments regulate such



operations at all, they do so by ordinances and codes



specifying the materials and methods of installation.  The



most frequent occurrence of leaks from underground pipes and



tanks is from these small systems.  Commonly, monitoring for



such leaks is by "discovery," when a nearby owner discovers



that his water well is contaminated.  Other examples occur



when an owner or operator discovers that the chemical is



disappearing from his tank faster than he is using it, or



when, during the rainy season the water table rises above



the level of a leak in a tank, the owner or operator



discovers that the tank is supplying water (Gilmore, 1973).



Monitoring methods and procedures for interstate carriers



are under the control of the Office of Pipeline Safety.  To



assure that interstate carrier monitoring and pipeline



operation are being done satisfactorily, the Office of



Pipeline Safety requires detailed reports of all leakage in



excess of 8000 liters of commodities from initiation of the



leak to the time of cessation.








Monitoring procedures have been developed and implemented by



interstate carriers, but they can be applied to any



underground tank or pipeline.  Pipelines contain pressure-
                            210

-------
monitoring devices that automatically close valves to



isolate a section of pipe whenever a significant pressure



loss occurs.  Regular checking of pipelines and tanks is



accomplished by throughput monitoring, periodic inspection,



and periodic pressure testing.








In all of these monitoring procedures emphasis has been on



hazard and on economics; in general, if the leak is so small



or so located that it constitutes no hazard (as defined by



the Office of Pipeline Safety), and the costs of repairing



the leaks are greater than the loss incurred by the leakage,



no attempt will te made to detect, locate, or repair the



leak.








Throughput monitoring.  Throughput monitoring compares input



and output.  This irethod will detect large leakage rates,



but small rates, comparable to the fluctuations in



difference between the input and output measurements



resulting from temperature cnanges, inaccuracies in the



measuring instruments, etc., will go undetected.  Improved



instrumentation might permit the detection of such leaks,



but usually they are detected by periodic inspections and



pressure tests.
                            211

-------
Periodic inspection.  Periodic inspection includes a visit



to the site and at least a visual inspection.  Often, if



volatile chemicals are involved, a tube is inserted into the



soil and air samples are drawn through portable gas



detectors.  The periodic inspection of pipelines usually



takes the form of a patrol on foot, by truck, or by



aircraft.  In all cases the dominant method of detection is



visual.  In addition to seeking direct evidence of pipeline



leaks,inspectors are adept at identifying leaks by their



effects on adjoining vegetation.








For tanks in lined excavations, liquid level sensors or



vapor sensors (fcr volatile fluids) can be placed in the



space between the lining of the excavation and the tank.



These are connected to an alarm located where personnel are



on duty.








Pressure tests.  Pressure tests are usually made on both



pipelines and tanks after repairs and periodically whenever



corrosion may be a problem.  A tank or a section of pipeline



is filled and pressurized and the pressure monitored.



Allowance is made for temperature change and expansion under



pressure and the degree of leakage, if any, is determined.
                            212

-------
The normal pressure-test duration is 24 hours.  A report



must be filed with the operator and the office of Pipeline



Safety.








This type of test is more sensitive than throughput



monitoring and periodic inspection, but because of the



potential variation of many parameters affecting the



pressure, small persistent leaks may go undetected and tests



may prove inconclusive.  An example of the ambiguity of such



a test resulted at Forest Lawn Cemetery in Los Angeles



County.  A pipeline near the cemetery was suspected as the



source of gasoline leakage, shown in Figure E.  It was



pressure tested, but some experts said that the results



indicated that the pipe was tight, while others felt that



the results indicated a small leak.  As of 1972, 189,000



liters of gasoline had been recovered at this site, and it



is estimated that the total spill amounted to 946,000



liters.








Monitoring solid radioactive wastes.  The monitoring methods



used for tanks containing radioactive wastes buried in pits



include sampling from sumps, wells, and surface water.



Laboratory analyses are made for beta and gamma activity and
                            213

-------
tritium content.  In practice, the methods are similar to



those for monitoring leachates from sanitary landfills.
                            214

-------
References
1.  Atomic Energy Commission,  "Category  VITT  -
    Services,"  The Nuclear Industry,  pp.  251-268 (1969).

2.  Bureau of Surface Transportation  Safety,  A  Systematic
    ABE roach to Pit^JLine Safety,  National Transportation
    Safety Board,"ftashingtonT  D.  C,   (1972).

    Committee on Environmental Affairs,  The Migration oj:
              Products in SoiJ. and Ground Water—Princijo
        Cojanterineasures, Publ.no. 4149,  Amer, Petroleum
    Inst, , Washington, D. C. ,  36  pp.  (1972).
<).  Department of Transportation,  "Title  49  -
    Transportation," federal Register,  v.  34,  no.  191,
    Washington, E> C. , 4 October  (1969).

5.  Department of Transportation,  "Part 195—
    Transportation," Federal Register,  v.  35,  no,  (>2,
    Washington, E.G., 31 March  (1970),

6.  Department of Transportation,  "Title  49  —
    Transportation," Federal Register, v.  35, no.  218,
    Washington, D.C», 7 November ll97Oa).

7,  Geraqhty, J.J. , "Movements  of  Contaminants"  Water  Well
    Jour., v. 16, October  (1961).

8.  Gilmore, D., Personal  Communication,  March (1973).

9,  Hepple, P.  (Ed.), The  Joint Problems  of  the  oil and
    Waiter Indu_strj.es, Proc. of  a Symposium Held  at the Motel
    Metropole, Brighton, 18-20  January  1967, The Institute
    of Petroleum, London,  England  (1967).

10. Jones, W.M.C., "Prevention  of  Water Pollution  from Oil
    Pipelines," Water Pollution by Oil, The  Institute  of
    Petroleum, London, England  (1971).

11. Laska, L., "Water Pollution Control in Alaska," Water,
    Air, and Soil Pollution, D. Reidel  Publishing  Co. ,  *~
    Dordrecht-Holland, pp. 415-432 (1972).
                            215

-------
12. Matis, J.R., "Petroleum Contamination  of  Groundwater in
    Maryland,"  Ground Water, v.  9,  no.  6,  pp.  57-61  (1971).

13. McKee, J.E., et al. , "Gasoline  in Groundwater," Jour._
    Water Pollution Control Federation,  v.  44,  pp.  293-302
    "(1972) ,

14. Office of Hazardous Materials,  Summary of Liguid
    J?i£§Ii,I,,£ Ac£i§,§Qts B§E2J£^ed on  DOT Form 7000-1  from
    3 $•££&£% I» i^i8 through December 31, 1968,  Dept.  of
    Transportation, Washington, D.  C.   (1969)".

15. Office of Pipeline Safety, Summary of  Liquid  Pipeline
    Accidents Reported on DOT Form  7000-1  from January 1^
    1^70 through December 3_1, 1970,  Dept.  of  Transportation,
    Washington, cT C.  (1971)".

16. Office of Pipeline Safety, Summary of  LjLgu^.d  Pipeline
    Accidents Reported on DOT Form  7(H)0^1  Trom January 1,
    JL2.Zi £ii£2iJ2li SSS^SlJb^E =li» J:5Zi»  Dept.  of  Transportation,
    Washington, C.~C.  (1972).

17. Office of the Secretary of Transportation,  "Title 49 -
    Transportation", Federal Register, v.  35, no.   5,
    Washington, C. C., 8 January  (T970).

18. Office of the Secretary of Transportation,  "Title 49 -
    Transportation," Federal Register, v.  36, no.  86,
    Washington, C. C. , 4~April  (1971)"-

19. Office of the Secretary of Transportation,  "Title 49 -
    Transportation," Federal Register, v.  37, no.  180,
    Washington, E. C., 15 September (1972).

20. Todd, O.K., Grcundwater Pollution in Euroge —  A
    Q2B£§£eQ5S Summary, GE73TMP-1,  Seneral Electric Co.,
    Santa Barbara, Calif., 79 pp.  (1973).

21. Toms, R.G., "Prevention of Oil  Pollution  from Minor
    Users," Water Pollution by Oil,  The  Institute of
    Petroleum, London, England  (1971).

22. Williams, D.E., and Wilder, D.G., "Gasoline Pollution of
    a Groundwater Reservoir—a Case History," Ground  Water,
    v. 9, no. 6, pp. 50-56  (1971).
                            216

-------
23.  Wood,  L.A.r "Groundwater Degradation—Causes and Cures,"
    Groundwater Duality and Treatment, Proc. of the 14th
    Water  Quality Conference, Univ. of Illinois, College of
    Engineering, Urbana-Champaign, pp. 19-25 (1972).
                             217

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                          APPENDIX
ADMINISTRATOR'S DECISION STATEMENT NO. 5
SUBJECT:  EPA POLICY ON SUBSURFACE EMPLACEMENT OF FLUIDS BY
         WELL INJECTION
    This ADS records the EPA's position on injection wells
and subsurface emplacement of fluids by well injection, and
supersedes the Federal Water Quality Administration's order
COM 5040.10 of October 15, 1970.
GOALS

    The EPA Policy on Subsurface Emplacement of Fluids by
Well Injection is designed to:

    1.   Protect the subsurface from pollution or other
         environmental hazards attributable to improper
         injection or ill-sited injection wells.

    2.   Ensure that engineering and geological safeguards
         adequate tc protect the integrity of the subsurface
         environment are adhered to in the preliminary
         investigation, design, construction, operation,
         monitoring and abandonment phases of injection well
         projects.

    3.   Encourage development of alternative means of
         disposal which afford greater environmental
         protection.
PR INCIP AL_ FINDIN G S_ AN D_^ POLI CY_ RATIONALE

    The available evidence concerning injection wells and
subsurface emplacement of fluids indicates that:
    1.    The emplacement of fluids by subsurface injection
         often is considered by government and private
         agencies as an attractive mechanism for final

-------
         disposal or storage owing to:   (1)  the diminishing
         capabilities of surface waters to receive effluents
         without violation of quality standards, and (2)  the
         apparent lower costs of this method of disposal  or
         storage over conventional and advanced waste
         management techniques.   Subsurface storage capacity
         is a natural resource of considerable value and
         like any other natural  resource its use must be
         conserved for maximal benefits to all people.

         Improper injection of municipal or industrial
         wastes or injection of  other fluids for storage  or
         disposal to the subsurface environment could result
         in serious pollution of water supplies or other
         environmental hazards.

         The effects of subsurface injection and the fate of
         injected materials are uncertain with today's
         knowledge and could result in serious pollution  or
         environmental damage requiring complex and costly
         solutions on a long-term basis.
POLICY AND PROGRAM,, GUIDANCE

    To ensure accomplishment of the subsurface protection
goals established above it is the policy of the
Environmental Protection Agency that:
         The EPA will oppose emplacement of materials by
         subsurface injection without strict controls and a
         clear demonstration that such emplacement will not
         interfere with present or potential use of the
         subsurface environment, contaminate ground water
         resources or otherwise damage the environment.

         All proposals for subsurface injection should be
         critically evaluated to determine that:

         (a) All reasonable alternative measures have been
         explored and found less satisfactory in terms of
         environmental protection;

         (b) Adequate preinjection tests have been made for
         predicting the fate of materials injected;
                             II

-------
 (c) There is conclusive technical evidence to
demonstrate that such injection will not interfere
with present or potential use of water resources
nor result in other environmental hazards;

 (d) The subsurface injection system has been
designed and constructed to provide maximal
environmental protection;

 (e) Provisions have been made for monitoring both
the injection operation arid the resulting effects
on the environment;

 (f) Contingency plans that will obviate any
environmental degradation have been prepared to
cope with all well shut-ins or any well failures;

 (g) Provision will be made for plugging injection
wells when abandoned and for monitoring plugs to
ensure their adequacy in providing continuous
environmental protection.

Where subsurface injection is practiced for waste
disposal, it will be recognized as a temporary
means of disposal until new technology becomes
available enabling more assured environmental
protection.

Where subsurface injection is practiced for
underground storage or for recycling of natural
fluids, it will be recognized that such practice
will cease or be modified when a hazard to natural
resources or the environment appears imminent.
The EPA will apply this policy to the extent of its
authorities in conducting all program activities,
including regulatory activities, research and
development, technical assistance to the States,
and the administration of the construction grants,
State program grants, and basin planning grants
programs and control of pollution at Federal
facilities in accordance with Executive Order
                               Signed 6 Feb. 1973
                            William  D.  Ruckelshaus
                                Administrator
                   III

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RECOMMENDED DATA REQUIREMENTS.. FOR. ENVIRONMENTAL F,VALUATION_

   OF SUBSURFACE EMPLACEMENT OF FLUIDS _BY_WELL_INJECTION

    The Administrator's Decision Statement Mo. 5 on
subsurface emplacement of fluids by well injection has been
prepared to establish the Agency* s position on the use of
this disposal and storage technique.  To aid in
implementation of the policy a recommended data base for
environmental evaluation has been developed.

    The following parameters describe the information which
should be provided by the injector and are designed to
provide regulatory agencies sufficient information to
evaluate the environmental acceptability of any proposed
well injection.

    (a) An accurate plat showing location and surface
elevation of proposed injection well site, surface features,
property boundaries, and surface and mineral ownership at an
approved scale.

    (b) Maps indicating location of water wells and all
other wells, mines or artificial penetrations, including but
not limited to oil and gas wells and exploratory or test
wells, showing depths, elevations and the deepest formation
penetrated within twice the calculated zone of influence of
the proposed project.  Plugging and abandonment records for
all oil and gas tests, and water wells, should accompany thf:
map.

    (c) Maps indicating vertical and lateral limits of
potable water supplies which would include both short-- and
long-term variations in surface water supplies and
subsurface aquifers containing water with less than 10,000
mg/1 total dissolved solids.  Available amounts and present
and potential uses of these waters, as well as projections
of public water supply requirements must be considered.

    (d) Descriptions of mineral resources present or
believed to be present in area of project and the effect of
this project on present or potential mineral resources in
the area.

    (e) Maps and cross sections at approved scales
illustrating detailed geologic structure and a stratigraphic
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section (including formations, lithology, and physical
characteristics) for the local area, and generalized maps
and cross sections illustrating the regional geologic
setting of the project.

    (f) Description of chemical, physical, and biological
properties and characteristics of the fluids to be injected.

    (g) Potentiometric maps at approved scales and isopleth
intervals of the proposed injection horizon and of those
aquifers immediately above and below the injection horizon,
with copies of all drill-stem test charts, extrapolations,
and data used in compiling such maps.

    (h) Description of the location and nature of present or
potentially useable minerals from the zone of influence.

    (i) Volume, rate, and injection pressure of the fluid.

    (j) The following geological and physical
characteristics cf, the injection interval and the overlying
and underlying impermeable barriers should be determined and
submitted:

          (1)  Thickness;

          (2)  areal extent;

          (3)  lithology;

          (>4)  grain mineralogy;

          (5)  type and mineralogy of matrix;

          (6)  clay content;

          (7)  clay mineralogy;

          (8)  effective porosity (including an explanation of
         how determined);

          (9)  permeability (including an explanation of how
         determined) ;

          (10)  coefficient of aquifer storage;
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     (11)  amount and  extent of  natural  fracturing;

     (12)  location, extent,  and effects of  known or
     suspected faulting  indicating whether  faults are
     sealed,  or fractured  avenues  for fluid movement;

     (13)  extent and  effects of natural solution
     channels;

     (14)  degree of fluid  saturation;

     (15)  formation fluid  chemistry (including local and
     regional variations) ;

     (16)  temperature  of formation (including an
     explanation of how  determined) ;

     (17)  formation and  fluid pressure  (including
     original and modifications resulting from fluid
     withdrawal or injection) ;

     (18)  fracturing  gradients;

     (19)  diffusion and  dispersion characteristics of
     the waste and the formation fluid  including effect
     of  gravity segregation;

     (20)  compatibility  of injected waste with the
     physical,  chemical  and biological  characteristics
     of  the reservoir; and

     (21)  injectivity profiles.

(k)  The  following engineering data should be supplied:

     (1)  Diameter of  hole  and total depth of well;

     (2)  type,  size,  weight, and strength,  of all
     surface, intermediate, and injection casing
     strings;

     (3)  specifications  and proposed installation of
     tubing and packers;
         proposed cementing procedures and type of
     cement;
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          (5) proposed coring program;

          (6) proposed formation testing program;

          (7) proposed logging program;

          (8) proposed artificial fracturing or  stimulation
         program;


          (9) proposed injection procedure;

          (10) plans of the surface and subsurface
         construction details of the system including
         engineering drawings and specifications of  the
         system  (including but not limited to pumps, well
         head construction, and casing depth);

          (11) plans for monitoring including a  multi-point
         fluid pressure monitoring system constructed  to
         monitor pressures above as well as within the
         injection zones; and description of annular fluid;

          (12) expected changes in pressure, rate of  native
         fluid displacement by injected fluid,  directions of
         dispersion and zone affected by the project;

          (13) contingency plans to cope with all shut-ins or
         well failures in a manner that will obviate any
         environmental degradation.

    (1)  Preparation of a report thoroughly investigating the
effects of the proposed subsurface injection well should be
a prerequisite for evaluation of a project.  Such a
statement should include a thorough assessment  of: 1)  the
alternative disposal schemes in terms of maximum
environmental protection; 2) projection of fluid pressure
response with time both in the injection zones  and overlying
formations, with particular attention to aquifers which may
be used for fresh water supplies in the future; and  3)
problems associated with possible chemical interactions
between injected wastes, formation fluids, and  mineralogical
constituents.
                                    SU.S GOVERNMENT PRINTING OFFICE 1973 -.-l.

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