EPA-R2-73-257
MAY 1973                 Environmental Protection Technology Series
     Water  Pollution
     and Associated Effects
     from  Street Salting
                                     National Environmental Research Center
                                     Office  of Research and Monitoring
                                     U.S. Environmental Protection Agency
                                     Cincinnati, Ohio 45268

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            RESEARCH REPORTING SERIES
Research reports of the  Office  of  Research  and
Monitoring,  Environmental Protection Agency, have
been grouped into five series.  These  five  broad
categories  were established to facilitate further
development  and  application   of   environmental
technology.   Elimination  of traditional grouping
was  consciously  planned  to  foster   technology
transfer   and  a  maximum  interface  in  related
fields.  The five series are:

   1.  Environmental Health Effects Research
   2.  Environmental Protection Technology
   3.  Ecological Research
   U.  Environmental Monitoring
   5.  Socioeconomic Environmental Studies

This report has been assigned to the ENVIRONMENTAL
PROTECTION   TECHNOLOGY   series.    This   series
describes   research   performed  to  develop  and
demonstrate   instrumentation,    equipment    and
methodology  to  repair  or  prevent environmental
degradation from point and  non-point  sources  of
pollution.  This work provides the new or improved
technology  required for the control and treatment
of pollution sources to meet environmental quality
standards.

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                                                 EPA-R2-73-257
                                                May  1973
         WATER POLLUTION AND  ASSOCIATED EFFECTS

                  FROM STREET SALTING
                            By
                  Richard Field,  Chief
       Storm and Combined Sewer Technology Branch
        Edison Water Quality  Research Laboratory
    National Environmental Research Center - Cinn.
                   Edison, New Jersey

                Edmund J. Struzeski, Jr.
Staff  Assistant to the Director of Technology  Programs
            Division of Field Investigations
          National Field Investigations Center
                     Denver,  Colorado

          Hugh E. Masters and Anthony N. Tafuri
                     Staff Engineers
        Storm and Combined Sewer Technology Branch
          Env.lv                •"- Agency
          Li:- -
          National Environmental Research, Center
           U.  S. Environmental  Protection Agency
                  Cincinnati, Ohio 45268
For sale by the Superintendent of Documents, U.S. Government Printing Office, Washington, D.C. 20402
            Price 85 cents domestic postpaid or 60 cents GPO Bookstore

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                 EPA Review Notice
This report has been reviewed by the Office of Research
and Monitoring, EPA, and approved for publication.
Approval does not signify that the contents necessarily
reflect the views and policies of the Environmental
Protection Agency, nor does mention of trade names or
commercial products constitute endorsement or recommendation
for use.


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                               ABSTRACT

     This report comprises a state-of-the-art review of highway deicing
practices and associated environmental effects.

     The bare pavement policy has resulted in a great increase in the use
of deicing salts, in many cases replacing the abrasives previously used.
However, no conclusive evidence has been found to substantiate that salt
usage makes winter travel safer.

     Besides chemical melting, various methods for anti-icing/deicing
are available or have been conceived (external and in-slab thermal melt-
ing systems; mobile thermal "snow melters"; compressed air or high speed
fluid streams in conjunction with snowplow blades or sweepers; snow/ice
adhesion reducing [hydrophobic/icephobic] substances; improved vehicular
and/or tire design)  which may become more prominent in the future especi-
ally when communities realize that a price must be paid to alleviate the
environmental effects of wintertime salting.

     Salt storage facilities often become a major contributing source of
local groundwater and surface water contamination and vegetation damage.
Coverage and proper drainage of salt piles is becoming more prevalent,
but there has not been an adequate acceptance of approved practices and
a proper recognition of pollutional problems associated with this mater-
ial storage.  Types of enclosed structures are illustrated, and cost con-
siderations given.

     High chloride concentration levels have been found in roadway runoff.
The special additives in deicing salts may create more severe pollutional
problems than the chloride salts.  Many roadside wells, due to contamina-
tion by salt laden runoff, have had to be replaced in such snow belt
states as New Hampshire, Maine, and Massachusetts.  Widespread damage
of roadside soils and vegetation has been observed in areas of liberal
salt usage.

     Areas of future research are also indicated in this report.
                                   111

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                         TABLE OP CONTENTS
                                                                 Page
ABSTRACT
FIGURES
TABLES
ACKNOWLEDGEMENT
 ill
  vi
viii
 ix
SECTION
    I    CONCLUSIONS                                               1
   II    RECOMMENDATIONS                                           3
              Resulting EPA Projects                               3
              Additional Needs                                     6
  III    INTRODUCTION                                              9
   IV    USE OF DEICING COMPOUNDS                                 11
    V    CHLORIDE SALT REDUCTION POSSIBILITIES                    17
   VI    SALT STORAGE                                             19
  VII    ENVIRONMENTAL EFFECTS FROM DEICING COMPOUNDS             27
              Runoff/ Sewage and Surface Streams                  27
              Farm Ponds and Lakes                                29
              Deicing Additives                                   29
              Ground and Surface Water Supply Contamination       31
              Vehicular and Roadway Damage                        34
              Soil, Vegetation and Trees                          34
VIII    REFERENCES                                                41

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                               FIGURES


Figure                          Title                           Page

   1   Twin-disc salt spreader with tail-gate screens            16
       (placed inside truck body)  to prevent salt
       lumps from reaching feeder ports

   2   New design salt spreader with screen grid over            16
       top to preclude salt lumps

   3   Open salt storage pile, downtown Chicago, Illinois        20

   4   Open salt storage pile, Milwaukee, Wisconsin,             20
       estimated quantity 41,000 tons

   5   Moving salt by front-end loader inside enclosed           21
       storage structure

   6   Covered salt stockpile located adjacent to the            21
       Maumee River in Toledo, Ohio

   7   Salt storage - Approximate construction cost              22
       $3 to $5 per Ton of capacity

   8   Salt storage - Approximate construction cost              22
       $3 to $5 per Ton of capacity

   9   Salt storage - Approximate construction cost              22
       $3 to $5 per Ton of capacity

  10   Salt storage - Approximate construction cost              23
       $50 to $75 per Ton of capacity

  11   Salt storage - Approximate construction cost              23
       $50 to $75 per Ton of capacity

  12   Salt storage - Approximate construction cost              23
       $50 to $75 per Ton of capacity

  13   Salt storage - Approximate construction cost              23
       $50 to $75 per Ton of capacity

  14   Salt storage - Approximate construction cost              24
       $15 to $20 per Ton of capacity

  15   Salt storage - Approximate construction cost              24
       $10 to $30 per Ton of capacity
                                 VI

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16   Salt storage - Approximate construction cost              24
     $20 to $30 per Ton of capacity

17   Salt storage crib                                         25

18   Salt storage shelter                                      25

19   Salt storage building                                     25

20   The "Beehive" - Salt storage structure; note              26
     air vents at top

21   The "Beehive" - Method of loading; first stage            26
     by truck and dozer

22   The "Beehive" - Method of loading; second stage           26
     by conveyor

23   Dumping snow into nearby waterway                         30

24   Chloride concentration of wells in the Burling-           32
     ton, Massachusetts Area, 1963-1971

25   Relatively healthy sugar maples photographed              35
     1960, Route 17, Durham-Middletown Line, Conn.

26   Same trees as above - those on left exhibiting            35
     salt damage, photographed 1965

27   Closeup of sugar maples exhibiting pronounced             36
     damage, Route 17, Durham-Middletown Line, Conn.

28   Healthy (right) vs. damaged sugar maple leaves            36
     (left), from right and left side of Route 17,
     respectively, Durham-Middletown Line, Conn.
                               VII

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                               TABLES

Table                           Title                          Page

   I   Conclusions (Abbreviated Listing)                        2

  II   Chloride Salt Reduction Possibilities                    4
       (Abbreviated Listing)

 III   Recommendations (Abbreviated Listing)                    8

  IV   Reported Use (Tons) of Sodium Chloride, Calcium         12
       Chloride and Abrasives by States and Regions in
       the United States, Winter of 1966-1967.

   V   High Chloride Values in Runoff                          28

  VI   Special River Sampling, Milwaukee Sewerage Com-         28
       mission, January 16, 1969

 VII   Salt Tolerance of Fruit Crops                           37

VIII   Salt Tolerance of Vegetable Crops                       38

  IX   Salt Tolerance of Field Crops                           38

   X   Salt Tolerance of Grasses and Forage Legumes            39

  XI   Salt Tolerance of Trees and Ornamentals                 40
                                Vlll

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                          ACKNOWLEDGEMENTS
     The authors express appreciation to Ms. Pauline Weigel, Staff
Assistant, Storm and Combined Sewer Technology Branch, National
Environmental Research Center-Cinn.,  EPA, Edison, New Jersey, for
her cooperation and assistance in editing.
                                  IX

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                             SECTION I
                           CONCLUSIONS-^
     Some of the more pertinent conclusions drawn from the study are as
follows:  (Table I presents a synoptic version)
     1.  Highway salts can cause injury and damage across a wide environ-
mental spectrum, and these effects although not yet evident in certain
areas of the country, may appear in the future.
     2.  Practically all highway authorities in the U.S. believe that
ice and snow must be removed quickly from roads and highways, and that
"bare pavement" conditions are necessary, often resulting in excessive
salt application.  Conclusive evidence is needed to substantiate using
salt to make winter travel safer.
     3.  Salt storage sites are persistent and frequent sources of ground
and surface water contamination, and vegetation damage.
     4.  The special additives found in road deicers provoke great con-
cern because of their severe latent toxic properties and other potential
side effects.  Significantly, little is known as to their fate and dis-
position.  Field investigations must provide considerably more data to
determine safe levels when using these additives.
     5.  A sufficient number of incidents and detailed studies have been
described to show the adverse impact of deicing salts to water supplies
and receiving waters.
     6.  In less severe cases of salt intrusion into public water sup-
plies, salt-free patients have been cautioned to change their potable
water source.
     7.  Deicing salts are found in high concentrations in highway runoff.
     8.  Surveillance data are needed to clearly define the many influences
of deicing salts upon the environment.
     9.  The majority of in-depth studies support the finding that deic-
ing salts are a major factor in vehicular corrosion and roadway damage.
The literature also indicates that rust inhibiting additives do not pro-
duce results to justify their continued use.  It is further noted that
deicers may attack and cause damage to telephone cables, water distribu-

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tion lines, and other utilities adjacent to streets and highways.

    10.  There is little doubt that road deicers can disturb a healthy

balance in soils, trees, and other vegetation comprising the roadside

environment.


                              TABLE I

                             CONCLUSIONS
                        (ABBREVIATED LISTING)

       1.  SALTS CAN CREATE VARIOUS ENVIRONMENTAL PROBLEMS

       2.  "BARE-PAVEMENT" IS GENERAL PHILOSOPHY 	 EXCESSIVE
           APPLICATION USUALLY RESULTS

       3.  STORAGE SITES CAN CAUSE POLLUTION

       4.  DEICING ADDITIVES INCREASE PROBLEMS

       5.  HIGH SALT CONCENTRATIONS FOUND IN HIGHWAY SNOWMELT

       6.  SALTS CAN CONTAMINATE WATER SUPPLIES AND RECEIVING WATERS

       7.  SALTS CAN BE DETRIMENTAL TO HEALTH

       8.  SALT MONITORING IS NEEDED

       9.  SALTS INCREASE CORROSION

      10.  SALTS CAN DAMAGE VEGETATION
I/ Selected from a more comprehensive listing of conclusions contained
   in the Edison Water Quality Research Laboratory report(3).

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                              SECTION II
                         RECOMMENDATIONS—
Resulting EPA Projects

     Two major projects have been instituted and sponsored by the U.S.
Environmental Protection Agency's Office of Research and Monitoring
which were based on recommendations from the state-of-the-art survey on
the environmental impacts of highway deicing.
     One of these projects, recently completed, involved a search for
new technology in snow and ice control by Abt Associates, Inc. (1) .
This work has covered the alternate concepts as highlighted by Table II.
It revealed that many studies have been made on ice adhesion in general
and that a few experiments have been performed on ice releasing agents
for aircraft and vessel exteriors, and outdoor mechanical equipment.
However, little has been done to directly investigate the use of such
agents on pavement.  The search indicated the high potential of using a
hydrophobic or icephobic (water or ice repellant) substance for ice con-
trol and further recommended that development be sought.
     Recognizing the importance of this recommendation, EPA prepared a
request for proposal (RFP).  The product of this KFP will be a study to
develop a hydrophobic or icephobic substance which can be used to reduce
the adhesion of ice or hard packed snow on pavements.  This study will
evaluate the relative merits of using these substances, once determined,
as an alternate to salt.  The study will be undertaken from the point of
view of finding an economical hydrophobic anti-icing/deicing agent which
can be placed on or within pavement surfaces and that would not have
irreversible harmful effects on the environment.  While this approach is
novel, it is potentially the most valuable alternative.
     Another study which is also being considered, as a result of recom-
mendations from the Abt Project, aims to carefully evaluate the environ-
mental and economic impacts of the continued use of deicing compounds in

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a more proper perspective.

                                    TABLE II
                     CHLORIDE SALT REDUCTION POSSIBILITIES
                             (ABBREVIATED LISTING)
            1.  EXTERNAL/IN-SLAB THERMAL MELTING
            2.  STATIONARY/MOBILE MELTERS
            3.  SUBSTITUTE DEICING COMPOUNDS
            4.  COMPRESSED AIR TYPE SNOWPLOW
            5.  ADHESION REDUCING PAVEMENT MATERIALS
            6.  SOLAR ENERGY STORING PAVEMENT SUBSTANCES
            7.  ELECTROMAGNETIC ICE SHATTERERS
            8.  IMPROVED DRAINAGE, ENHANCING RUNOFF, ACCIDENT
                REDUCTION, AND SNOWMELT CONTROL/TREATMENT
            9.  SALT RETRIEVAL/TREATMENT
           10.  IMPROVED TIRE/VEHICULAR DESIGN

     The second, and larger project(2) will provide the following:
     1.  A Deicer Users Manual, to describe snow and ice removal practices
and the best systems of applying deicing chemicals to streets and highways.
(Several highway agencies and the salt industry are known to have various
instructional material that are principally directed to operational per-
formance.  The best data in this area will be incorporated into the Manual.
Pollution of the surrounding environment and potential in cost savings do
not warrant excessive saltings, and the Deicer Users Manual will give
utmost priority to environmental protection.)  More specifically, the
manual will include:
         a.  Absolute minimum amounts of deicing chemicals necessary to
maintain safe traffic flows;
         b.  Critical points or placement of application;
         c.  Higher degree of instrumentation, improved calibration, and

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increased reliability of existing and new deicing equipment;
         d.  Incorporation of applicable weather detection, prediction,
and warning systems as a basis for projecting manpower, equipment, and
material requirements for combatting winter storms more efficiently and
effectively;
         e.  Proper maintenance and repair schedules;
         f.  Methods of salt spreading to optimize operational and man-
power efficiencies;
         g.  A rating test(s) for materials and methods;
         h.  Suggested prime systems and alternatives;
         i.  Canadian, European, and British practices as they may apply;
and
         j.  Model codes or ordinances for using deicing compounds.
     2.  A Manual of Design and Recommended Practices for Storage Facil-
ities and Methods of Handling Deicing Materials Throughout Storage.   (Al-
though certain instructional materials are available from highway agencies
and the salt industry on proper salt storage, there has not been an
adequate acceptance of approved practices, and a proper recognition of
pollution problems associated with materials storage.  Many storage sites
are located on marginal lands adjacent to streams and rivers with the de-
icing materials often stockpiled unprotected in open areas, and too freq-
uently these sites have become chronic sources of ground and surface
water pollution.)  This Manual will describe:
         a.  Proper siting of materials storage to eliminate pollution;
         b.  Adequate covering of storage sites to protect materials and
preclude surface drainage;
         c.  Suggested design of storage facilities, particularly shielded
structures;
         d.  Adequate foundation and footing;
         e.  Sequence and timing of materials delivery;
         f.  Alternative methods for preventing caking of salt materials
including physical, mechanical, and chemical techniques; and
         g.  Drainage requirements for all storage sites including those
of salt manufacturers.

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     The aforementioned Deicer Users and Storage Manuals will include
important information necessary for policy making and management.
     3.  An evaluation of the pollutional magnitude from continued prac-
tices of removing and dumping the enormous quantities of snow from streets
and highways into nearby water bodies or onto water supply watersheds.
Particular studies will be undertaken to:
        a.  Determine the characteristics and quantities of the snow now
being disposed of in several selected locations within the snowbelt states;
        b.  Identify the areas and specific locations where the snow is
being disposed of (such as, water bodies and water supply watersheds);
        c.  Monitor the depository, before and after dumping, for time
effects, unit pollutant loads, and any other detrimental effects upon it
from the melted snow;
        d.  Summarize the toxic materials found in the snow from the
various snow dump test sites;
        e.  Develop model codes or regulations for the practice of snow
dumping;
        f.  Forecast what effect technological advances are expected to
have upon the future snow accumulations in the previously selected loca-
tions of investigation.  (New snow disposal practices will be compared
from an economic and technical standpoint); and
        g.  Develop recommendations for specific changes in existing
snow removal practices that are considered environmentally unacceptable.
     Present program work plans anticipate relating feasible project recom-
mendations for deicer alternatives into full-scale, municipal demonstra-
tion (s) .

Additional Needs
     In addition to the present work being carried out, the following
are recommended:  (Table III presents a synoptic version of these recom-
mendations)
     1.  Foster increased recognition of the problem at various govern-
mental levels which would include accelerated training, environmental
impact awareness, and demonstration of optimum procedures and techniques

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in wintertime deicing.
     2.  Carry forth detailed studies both in the laboratory and field
on the various toxic and nutrient additives mixed with deicing materials
so as to determine their potential hazards and safe levels of use.
     3.  Initiate a program for obtaining base-line data on long-term
environmental changes that may be taking place due to the increasing
use of deicing chemicals.  Data are especially needed on deicing chem-
icals in surface and groundwaters; in selected soils and vegetation; and
the deterioration levels prevailing among salt-affected vehicular traffic,
highway pavements and structures, and underground utilities.
     4.  Consideration be given by the various governmental authorities
in roadway design to reduce deicing requirements, and enhance the con-
trol, collection, and treatment of ensuing salt runoff.
     5.  Various suppliers and highway authorities make available full
information on marine salts - their current and future expected use in
highway deicing, chemical composition, physical properties including
melting efficiencies, and comparison with the common chloride salts.
Evaluation of the pollutional impact of marine salts should be made as
soon as possible.
     6.  Information be compiled and disseminated, and in other cases
developed, on best selection of roadside plantings, and the various
remedial measures for restoring roadside soils and vegetation damaged
by deicing chemicals.
     7.  Findings of past studies dealing with vehicular corrosion, dete-
rioration of highway pavements, structures, and utilities, potentially
caused by road deicers, be made readily available for further study and
use.
     8.  Various suppliers and users of highway deicers investigate and
present information on the merits and demerits of various substitute
materials that may be used in place of the common chloride salts.  A
major objective is to identify those deicers having high efficiency and
demonstrating minimum side effects.
     9.  Conduct studies to determine the use of deicing salts with re-
gard to the purpose for which they are intended, i.e., making winter
driving safer.

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                              TABLE III

                           RECOMMENDATIONS
                        (ABBREVIATED LISTING)

      1.  FOSTER PROBLEM RECOGNITION AND ALLEVIATION METHODS

      2.  INVESTIGATE  TOXIC ADDITIVE EFFECTS

      3.  ESTABLISH  ENVIRONMENTAL BASE-LINE DATA

      4.  REDUCE SALT  POLLUTION BY IMPROVED HIGHWAY DESIGN

      5.  FURTHER INVESTIGATE MARINE SALT IMPACTS

      6.  IMPROVE ROADSIDE  CONDITIONS

         — Better  Plant Selection

          — Soil and  Vegetation Restoration

      7.  FURTHER EVALUATE  VEHICULAR AND ROADSIDE CORROSION

      8.  FURTHER INVESTIGATE SALT SUBSTITUTES

      9.  SUBSTANTIATE THAT SALT USAGE MAKES WINTER TRAVEL SAFER
I/ Selected from a more comprehensive listing of recommendations  contained
   in the Edison Water Quality Research Laboratory  report(3).

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                            SECTION III

                            INTRODUCTION

     Salt contamination in runoff is generated by storm events.  Accord-
ingly, countermeasures for this form of pollution are being investigated
by the U.S. Environmental Protection Agency's Storm and Combined Sewer
Pollution Control Research, Development, and Demonstration Program.
     This report comprises a state-of-the-art review of highway deicing
practices and associated environmental effects, and offers a critical
summary of the available information on:
     1.  Methods, equipment, and materials used for snow and ice removal;
     2.  Chlorides found in rainfall and municipal sewage during the
winter;
     3.  Salt runoff from streets and highways;
     4.  Deicing compounds found in surface streams, public water sup-
plies, groundwater, farm ponds, and lakes;
     5.  Special nutritious or toxic additives incorporated into deic-
ing agents;
     6.  Vehicular corrosion and deterioration of highway structures and
pavements attributable to salting; and
     7.  Effects of deicing compounds on roadside soils, vegetation and
trees.

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                             SECTION IV

                      USE OF DEICING COMPOUNDS

     It has been found from a study(3) that the current annual use of high-
way deicers is approximately 9 to 10 million tons of sodium chloride, 0.3
million tons of calcium chloride, and about 11 million tons of abra-
sives (3-5).  Reported amounts of these materials deployed for highway
deicing by individual States and Regions during the winter of 1966-1967
are presented in Table IV.  Twenty-one states in the eastern and north-
central sectors of the country use more than 90 percent of all chloride
compound deicers.  Leading States in deicer use are Pennsylvania, Ohio,
New York, Michigan and Minnesota.  It is noted that the State of New
Hampshire, although relatively small in area, has used highway salts since
the mid-40's, and over this period the cumulative use of highway salts in
this State alone has probably exceeded 2.3 million tons.
     The demand that roads be safe and usable at all times, and that June
driving conditions be provided in January, has in recent years led to
adoption of a "bare-pavement" policy by practically all highway depart-
ments in the snow belt region.  As a result, the use of deicing salts has
greatly increased and in many cases has replaced the abrasives previously
used.  Unfortunately, the more damaging chlorides are more efficient in
melting snow and ice, won't be blown off the road as easily by wind and
traffic, require less application time, and are less costly both in appli-
cation and cleanup.  At the end of the winter, large amounts of abrasives
must be retrieved from shoulder areas, catch basins, and conduits in order
to establish proper road drainage(6);  whereas chemical deicers directly
attack and melt the ice and packed snow surfaces.  The salt dissolves the
ice and most importantly, causes a break in the tight bonding of ice to
pavement.  Chemicals also prevent the formation of new ice.  The result-
ing salt residue is then readily washed off the pavement.
     Marine salts have shown to be comparable in cost/effectiveness to
rock salt and are receiving use for highway deicing(6).  These salts are
probably being sold separately or mixed together with commercial rock

                                 11

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                              TABLE IV
      REPORTED USE (TONS)  OF SODIUM CHLORIDE, CALCIUM CHLORIDE,
      AND ABRASIVES BY STATES AND REGIONS IN THE UNITED STATES,
                      WINTER OF 1966-1967^—•
           STATE
 SODIUM
CHLORIDE
CALCIUM
CHLORIDE
ABRASIVES
      EASTERN STATES
Maine
New Hamsphire
Vermont
Massachusetts
Connecticut
Rhode Island
New York
Pennsylvania
New Jersey
Delaware
Maryland
Virginia
99,000
118,000
89,000
190,000
101,000
47,000
472,000
592,000
51,000
7,000
132,000
77,000
1,000
-
1,000
6,000
3,000
1,000
5,000
45,000
6,000
1,000
1,000
22,000
324,000
26,000
89,000
423,000
335,000
86,000
1,694,000
1,162,000
70,000
2,000
40,000
204,000
                          1,975,000
                 92,000
            4,455,000
   NORTH-CENTRAL STATES
Ohio
West Virginia
Kentucky
Indiana
Illinois
Michigan
Wisconsin
Minnesota
North Dakota
511,000
55,000
60,000
237,000
249,000
409,000
225,000
398,000
2,000
12,000
9,000
1,000
6,000
10,000
7,000
3,000
14,000
1,000
43,000
230,000
-
77,000
60,000
6,000
102,000
84,000
13,000
                          2,146,000
                 63,000
              615,000
    SOUTHERN STATES
Arkansas
Tennessee
North Carolina
Mississippi
Alabama
Georgia
South Carolina
Louisiana
Florida
  1,000

 17,000
 2,000
  75,000
                             18,000
                  2,000
                75,000
                                 12

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     WEST-CENTRAL STATES
Iowa
Missouri
Kansas
South Dakota
Nebraska
Colorado
     SOUTHWEST STATES
Oklahoma
New Mexico
Texas
     WESTERN STATES
Washington
Idaho
Montana
Oregon
Wyoming
California
Nevada
Utah
Arizona
District of Columbia

1966-1967 REPORTED
TOTALS—
   54,000
   34,000
   25,000
    2,000
   10,000
    7,000

  132,000
    7,000
    7,000
    3,000
   17,000
    2,000
    1,000
    4,000
    1,000
    1,000
   11,000
    4,000
   28,000


   52,000

   36,000

4,376,000
 2,000
 3,000
 2,000
 1,000
                                              8,000
165,000
  291,000

   31,000
   36,000
    6,000
  150,000

  291,000
                2,000

                1, OOP

                3,000
              155,000
               47,000
               80,000
              200,000
               43,000
               94,000
               50,000
               56,000


              725,000
6,164,000
a/  Data taken from Salt Institute 1966-1967 Survey for U.S. and
    Canada(4).
b/  Represents data by all governmental authorities reporting within
    each State.
£/  Overall values given in Table IV represent about 75 percent of true
    values (reported and unreported) of salts and abrasives used in
    1966-1967.  With confidential data and appropriate adjustments,
    the Salt Institute estimates that U.S. total consumption for the
    winter 1966-1967 was 6,320,000 tons sodium chloride, 247,000 tons
    calcium chloride, and 8,400 tons abrasives.
                                 13

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salt amounting to hundreds of thousands of tons annually.  It is known
that the major constituents in sea water approximate 30.5% sodium, 55.1%
chlorides, 3.7% magnesium, 7.7% sulfates, 1.2% calcium, 1.1% potassium,
0.2% bromides, and 0.4% bicarbonates and carbonates(7-9).  Although com-
merical marine salts exclude impurities to a large extent, information
on product composition is not readily available.  Further marine salt
data are definitely required on composition; comparative deicing effi-
ciency; and significantly, the potential consequences of sulfates, mag-
nesium, potassium and other available constituents possibly contributing
to environmental pollution.
     Highway salting rates are generally in the range of 400 to 1,200
pounds of salt per mile of highway, per application(10-12).  Over the
winter season, many roads and highways in the U.S. may receive more than
20 tons of salt per lane mile, or more than 100 tons per road mile.
     Considerable wasting of highway deicers undoubtedly occurs because
of excessive application, misdirected spreading, and general wintertime
difficulties.  In some cases, salts are applied as soon as or even before
snow occurs, based upon weather forecast probability.  It is believed that
there have been frequent instances where highway salts were used but no
snow followed.
     Environmental problems are minimized by deploying chemicals as spar-
ingly as possible to maintain "bare-pavement" conditions.  The proper
application and spreading efficiency of highway salts have generated some
studies but nonetheless this area has not received deserved attention.
The Highway Research Board in a 1967 report(15) indicates several chal-
lenges presented by previous research findings, one being to improve
present maintenance practices including the over-application of highway
salts where conditions do not warrant; poor regulation of spreading
equipment which distributes salt material beyond the pavement break; and
too many improperly located and inadequately-protected stockpiles of
chloride salts.  Greene(16) cites the viewpoint of the Bureau of Public
Roads that improper calibration of salt spreaders is extremely common.
This along with improper operation of equipment leads to excessive salt
application rates, which not only increases over-all costs but also con-

                                  14

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tributes to the damage of vegetation and water supplies/ and the dete-
rioration of concrete pavement and structures.  In Ontario, it is claimed
$1 million per year is saved by better application of highway salts(16).
Over recent years salt use in the State of Maine is reported to have been
reduced some 30,000 tons annually due to improved practices(11).  Greene
estimates operational savings of several million dollars per year are
possible Nation-wide without reducing the quality of wintertime road
maintenance(16).  Significant improvements in wintertime road maintenance
practices would be derived from better field testing and control, good
equipment with good maintenance schedules, greater use of mechanized
equipment, frequent calibration, increased reliance and improvement of
salt metering instrumentation, education and awareness through the ranks
particularly at the working level, concerted effort and increased train-
ing carried forth at the state highway department level, and due con-
sideration to environmental protection.
     Various types of snow-control equipment are used, two of which are
shown in Figures 1 and 2.   These figures show the use of screen grids in
salt spreaders for precluding problems with salt lumps.  Other new salt
spreader designs include "electronically-controlled" 10-wheel vehicles,
capable of distributing 14 cubic yards of salt before reloading(13,14).
We should not neglect the possible use of sweepers as a substitute for
snow plows to alleviate pavement damage.  This snow removal mechanism
could also allow direct snow pick-up as opposed to just pushing it aside.
                                 15

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                  FIGURE 1
   Twin-disc salt spreader with  tail-gate
screens (placed inside truck  body)  to  prevent
    salt lumps from reaching  feeder ports
                   FIGURE 2
     New design salt spreader with screen
     grid over top to preclude salt lumps
                       16

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                             SECTION V

                 CHLORIDE SALT REDUCTION POSSIBILITIES

     Besides chemical melting, various methods for deicing are available
or have been conceived which may become more prominent in the future
especially when communities realize that a price must be paid to alle-
viate the pollutional effects of wintertime salting.  Some of these
methods are:
     1.  External and in-slab thermal melting systems;
     2.  Stationary (or pit) and mobile thermal "snow melters";
     3.  Substitute deicing compounds;
     4.  Compressed air or high speed fluid streams in conjunction with
snowplow blade or sweepers to loosen pavement bond and lift snow;
     5.  Snow adhesion reducing substances in pavement;
     6.  Pavement substances that store and release solar energy for
melting;
     7.  Electromagnetic energy to shatter ice;
     8.  Road and drainage design modifications to enhance runoff, reduce
wintertime accidents, and capture snowmelt for treatment or control;
     9.  Salt retrieval or treatment possibly enhanced by the addition
of chelating agents; and
    10.  Improved tire or vehicular design to reduce deicer requirements.
Although it is recongized that power, maintenance, and chemical costs for
the above systems are high when compared to rock salt, municipalities,
such as Burlington, Massachusetts have expressed(17) a deep willingness
to explore and demonstrate new methods regardless of cost.  Burlington
has recently suspended roadway salting practices when a study(17-19) in-
dicated that their well water chloride concentrations could exceed the
recommended limit of 250 mg/l(20,21)  if salting was continued.   It should
also be pointed out that experience,  operational data, and knowledge of
environmental effects are lacking for the substitute chemical deicers.
                                  17

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                              SECTION VI

                            SALT STORAGE

     Salt storage is needed for sustaining highway deicing operations,
but too frequently these facilities, which concentrate great quantities
of salt, become a major contributing source of local ground and surface
water salt contamination.  Because of water supply contamination, desir-
ability of better product handling, and aesthetic improvements, many
communities have turned to covering of salt piles, enclosed structures,
and the diversion of collection of salt-laden drainage(22,23) .  Typical
open salt storage areas in Chicago and Milwaukee are shown in Figures 3
and 4.  Figures 5 and 6 illustrate covered salt stockpiles in New York
City and Toledo, Ohio, which again from a water pollution control stand-
point, are highly preferred over open storage.
     Example sketches of the types of salt storage facilities most fre-
quently used in the United States are illustrated in Figures 7 to 19.  It
is noted that construction costs as given for these storage facilities
were prepared around 1965, and are undoubtedly somewhat below current
estimates.  The more expensive structures are often reported to be the
least expensive to use depending on local climate, amounts of stored
materials, type of equipment available, and services.
     Fitzpatrick(24) of the Ontario Department of Highways has described
a dome-like structure or "beehive", as shown in Figure 20, which is now
being used to store large quantities of sand-salt mixtures in the Province.
The "beehive" is rather unique in storing up to 5,000 cubic yards of sand-
salt under one roof with a clear span free of posts, poles or pillars.
The structure has a 100 foot base diameter and is 50 feet high.  Trucks,
front-end loaders and other equipment, as shown by Figures 21 and 22, can
easily move about the structure for loading and unloading thus alleviating
the pollution effects from spillage in open areas.  Costs are reported
around $5.00-$6.00 per ton of sand-salt mixture stored (approximately
equal to $3.50 per square foot of floor area)(24).
                                  19

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                   FIGURE 3
Open salt storage pile, downtown  Chicago,  111
                                                    Courtesy of city of
                                                     Chicago, Illinois
                   FIGURE 4
    Open salt storage pile, Milwaukee, Wis,
        estimated quantity 41,000 tons
                      20

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           FIGURE 5

     g Sa]t by f™nt-end loader
      enclosed storage structure

          FIGURE 6

 u S2U stockPHe located adjacent
the Maumee River in Toledo,  Ohio
            21

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                          FIGURE  7


    Approx.  Construction  Cost  $3  to  $5  per  ton  of  capacity
Rock salt can easily be stored outdoors.   This  shows  a  rec-
 tangular-conical  pile of bulk salt covered by  a  tarpaulin
  held down by stakes.   The  platform is  approximately 30'
  square and is composed of  3" planks  held up by  4" by  4"
 wood sills.  It will  hold approximately a 40-ton minimum
                  carload of bulk  salt.
                           FIGURE 8


     Approx. Construction Cost $3 to $5 per ton of capacity
   Rock salt may also be stacked against a garage or shed wall.
   Here a portable conveyor stacks it.  The pile is covered by
    a tarpaulin and anchored at the lower end by large rocks.
                           FIGURE 9


     Approx. Construction Cost $3 to $5 per ton of capacity
                                   f P "• COflfuCA rio
                                                                Courtesy  of  the
                                                                Salt  Institute,
                                                                Alexandria,  Va.
 Open bin storage like this is favored by many Ohio communities,
   and the dimensions shown here are given to scale.  The roof
   has a very large overhang in order to protect the open salt
   from the weather.  Trucks are backed up to the bins and the
   salt is partly dumped and partly shoveled in.  It is removed
   by shoveling into trucks, or portable conveyors may be used.
                              22

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                    FIGURE 10
                                                                                  FIGURE  11
           Approx. Construction Cost
         $50 to $75 per ton of capacity
       Approx. Construction Cost
     $50 to $75 per ton of capacity
                                                                                            D
    Standard steel  bins  like  those  used  by
    contractors  for cement, sand  and  gravel
      provide excellent  rock  salt storage
    space.   Dump trucks  feed  salt into the
    portable conveyor, which  carries  it  up
                  to the bin.
 The same type of bin  as  that shown  in
Figure 10, except that a  vertical  chain
     and bucket elevator  is  used.
                  FIGURE 12
                                                                                   FIGURE 13
           Approx. Construction Cost
          $50 to $75 per ton of capacity
        Approx. Construction Cost
      $50 to $75 per ton of capacity
   In hilly communities  the  bin  may  be
placed close to a hillside to facilitate
                loading.
  This variation on the bin in Figure 12
      follows the contour of the hill.
                                                    23
                                                                                         Courtesy of the
                                                                                         Salt Institute,
                                                                                         Alexandria, Va.

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                          FIGURE  14


  Approx.  Construction Cost $15  to $20  per ton  of  capacity
 Many communities  use this  method  of storing  bags  of  rock  salt
 outdoors.   The sketch shows  50  tons of bags  placed on  a plat-
   form about 30'  wide with the  bags many  layers deep.  The
 planks are 3" and supported  by  4"  by 4" sills.  The  bags  are
  covered by a tarpaulin held down  by rocks.   Note the  method
of piling bags on  the outside of the pile.  Trucks are  apt to
 bump into the pile while backing  up for loading,  and it is
important that the stacking be in  such a way  that  the bags stay
             firmly in place  or  else fall  inward.
                           FIGURE 15


   Approx. Construction Cost $10 to $30 per ton of capacity
   Bulk salt stored under a  shed.   The  salt  is  loaded  in by  a
  portable conveyor, which is  also  used for  getting  it  out and
                 onto trucks for distribution.
                            FIGURE 16


    Approx. Construction Cost $20 to $30 per ton of capacity
This piling arrangement, similar to that in Figure 14 features
a platform about 3' off the ground in order to facilitate load-
 ing onto trucks.  Under these conditions, the storage is not
over 40 tons of salt as a rule.  The tarpaulin is held in place
               by tying underneath to the posts.
                                  24
                                                                          Courtesy of the
                                                                          Salt Institute,
                                                                          Alexandria, Va

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                                                                                FIGURE  17


                                                                           Salt  Storage Crib
                                                        Here  is  a  crib with walls built of 2 x 6 tongue and
                                                      grooved creosote treated material.  Posts are railroad
                                                    ties set  three feet apart on center.  Note the 2x4 cleat
                                                       nailed to crib wall posts as tie-down for tarpaulin or
                                                                         other covering.
                 FIGURE  18


            Salt Storage Shelter
Umbrella structure  protects  material  from weather
   Panel on both  sides  keeps salt  from  collect-
            ing around  posts.
                                                                                                Courtesy of the
                                                                                                Salt Institute,
                                                                                                Alexandria, Va.
                                                                FIGURE  19

                                                          Salt  Storage  Building
                                                Tie  corner posts  of storage buildings together with
                                                  underground  galvanized cables with turnbuckles.
                                                    25

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  The "Beehive" -
Method of loading;
  first stage by
 truck and dozer
                                                           FIGURE 20

                                                        The "Beehive" -
                                                    Salt Storage Structure;
                                                     note air vents at top
                                                          FIGURE  22
                                                       The "Beehive"  -
                                                     Method of loading;
                                                       second stage by
                                                          conveyor
                                  26

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                            SECTION VII

            ENVIRONMENTAL EFFECTS FROM DEICING COMPOUNDS

Runoff, Sewage, and Surface streams

     Street runoff from the melting of ice and snow mixed with chloride
salts, finds its way via combined and sanitary sewers to the local sewage
treatment plant and then to the streams; and also via storm sewers to
nearby receiving waters.  Daily chloride loads were shown to be 40 to 50
percent higher for winter months as compared to summer months in municipal
sewage at Milwaukee, Wisconsin(12,25).  During days of heavy snow-melt,
daily chloride loads were three-fold the normal summertime loads.  Cal-
culations (10) show that 600 pounds of salt when applied to a one-mile
section of roadway 20 feet wide containing 0.2 inches of ice, will pro-
                                              o
duce an initial salt solution of 69,000 (at 10 F) mg/1 to 200,000 (at
25 F) mg/1.  Street runoff samples collected from a downtown Chicago ex-
pressway in the winter of 1967 showed chloride contents from 11,000 to
25,000 mg/l(26,27).  Table V illustrates some high chloride concentration
values found in runoff.
     At Milwaukee, on January 16, 1969, extremely high chloride levels of
1,510 to 2,730 mg/1 found in the Milwaukee, Menomonee, and Kinnickinnic
Rivers, were believed directly attributable to deicing salts entering
these streams from highway snow melt(23).   Table VI contains the Milwaukee
results.  Meadow Brook in Syracuse, New York contained chloride concentra-
tions usually in the range of 200 to 1,000 mg/1, but frequently exceeded
a few thousand mg/1(29).  For example,  a sample in December showed about
11,000 mg/1 chlorides in the Meadow Brook watershed(27).   From the limited
data available on streams, increasing chloride trends are evident for
some large rivers in the U.S.(10).  Wintertime highway runoff eventually
running into freshwater streams and natural or man-made lakes or ponding
areas may have adverse effects upon water life in the future(10,24).
     The dumping of extremely large amounts of accumulated snow and ice
from streets and highways, either directly or indirectly into nearby water

                                 27

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                                   TABLE V
    Location

Chippewa Falls,
Wise.

Madison, Wise.

Lake Monona
Wise.

Chicago, 111.
Des Moines, Iowa
                        HIGH CHLORIDE VALUES IN RUNOFF

                                              Chlorides
   Source

Highway


Street

Snow Pile
  Date      (mg/1)
Reference
1956-1957   10,250    Schraufnagel (12)


1956-1957    3,275    Schraufnagel (12)

1956-1957    1,130    Schraufnagel (12)
JFK Express-    1966-1967   25,100    Schraufnagel  (26,27)
way

Cummins Pkwy.   1958-1969    2,720    Henningson, et al.  (28)
Storm Drain
                                  TABLE VI
              SPECIAL RIVER SAMPLING, MILWAUKEE SEWERAGE COMMISSION,
                               January 16, 1969^-
           Location

  Kinnickinnic River at
     Chase Avenue

  Menomonee River at 13th St.
     and Muskego

  Menomonee River at 70th and
     Honey Creek Pkwy.

  Milwaukee River at Silver
     Spring Road

  Milwaukee River at Port
     Washington Road
                      Water
                 Temperature( C)

                       10.0


                       10.5


                        5.0


                        4.0


                        6.5
                       Chlorides  (mg/1)

                              2,005


                                200


                              2,730


                              2,680


                              1,510
  a/  Records received from the Milwaukee Sewerage Commission, May 1970(25)
                                        28

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bodies could constitute a serious pollution problem.  These deposits have
been shown(30) to contain up to 10,000 mg/1 sodium chloride, 100 mg/1 oils,
and 100 mg/1 lead.  The latter two constituents attributable to automotive
exhaust.  Figure 23 shows a dumping operation.

Farm Ponds and Lakes

     Effects of highway salts upon farm ponds and as a cause of induced
stratification in lakes have been described by various investigators.  A
1966-1968 survey of twenty-seven farm ponds along various highways in the
State of Maine showed that road salts have strong seasonal influence on
the chloride level of these waters, and that salt concentrations were in-
creasing yearly(10,26,31,32).  Density stratification of chlorides was
observed in Beaver Dam Lake at Cumberland, Wisconsin(12); in First Sister
Lake near Ann Arbor, Michigan(33); and Irondequoit Bay at Rochester, New
York(34), all three cases attributed to salt runoff from nearby streets
entering these lakes.  It has also been estimated that highway salts con-
tribute 11 percent of the total input of waste chlorides entering Lake
Erie annually(10,35).  Sodium from road salts entering streams and lakes
may additionally serve to increase existing levels of one of the mono-
valent ions essential for optimum growth of blue-green algae, thereby
stimulating nuisance algal blooms(36,37).
     Recent investigations(38)  have brought attention to the hazardous
potential of sodium and calcium ion exchange with mercury tied up in
bottom muds.  This could release highly toxic mercury to the overlying
fresh waters.  Undoubtedly other poisonous heavy metals can also be re-
leased in this manner.

Deicing Additives

     Special additives present within much of the highway salts sold today
may create pollutional problems(39) even more severe than caused by the
chloride salts(40).   Ferric ferrocyanide and sodium ferrocyanide are com-
monly used to minimize the caking of salt stocks(12).  The sodium form

                                   29

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            FIGURE 23
Dumping snow into nearby waterway
               30

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in particular, is quite soluble in water, and will generate cyanide in
the presence of sunlight(10).  Tests by the State of Wisconsin showed that
15.5 mg/1 of the sodium salt can produce 3.8 mg/1 cyanide after 30 min-
utes (10,12).  Maximum levels of cyanide allowed in public water supplies
range from 0.2 to 0.1 mg/1(20,41).  Chromate and nutritious phosphate(10,
12) additives are used in deicers as corrosion inhibitors(10,12,40).  As
with cyanide, chromium is a highly toxic ion(40), and limits permitted in
drinking and other waters are in the same low range(20,41).  During the
winter of 1965-1966 in the Minneapolis-St. Paul area, snow melt samples
showed maximum levels of 24 mg/1 sodium chromate, 1.7 mg/1 hexavalent
chromium, and 3.9 mg/1 total chromium(40).

Ground and Surface Water Supply Contamination

     Serious groundwater pollution has occurred in many locations due to
the heavy application of salts onto highways and inadequate protection
given to salt storage areas(6,10,17-19,31,32,42-56).  The State of New
Hampshire up to 1965, is reported to have replaced more than 200 road-
side wells, due to contamination by road salts.  Some of these wells had
contained in excess of 3,500 mg/1 chlorides(10,49).  In Manistee County,
Michigan, a roadside well located 300 feet from a highway department salt
storage pile, was found to contain 4,400 mg/1 chlorides(10,43).  Tastes
and odors in domestic water supplies in Connecticut have been traced to
chlorides and sodium ferrocyanide originating from salt storage areas(51).
Within Massachusetts, salt increases have been noted in the water supplies
of some 63 communities(19,42,57), and various supplies have been abandoned
at least in part due to road salting and salt storage piles(17-19,42,50,
52,53,57).
     The previously cited Town of Burlington,-^Massachusetts conducted a
study(17,18)  indicating area wells are becoming .increasingly high in
chlorides as shown in Figure 24.  If this chloride concentration were to
increase at the rate shown, water supplied by these Burlington wells could
soon exceed the upper limit of 250 mg/1 chloride established by the U.S.
Public Health Service(20), a condition which could possibly force closing

                                 31

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                                                              00
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CM
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10
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                                         9 *
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                                 FIGURE 24


                                     32

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of wells.  It should be emphasized that a desirable concentration of
chlorides is considered to be 25 mg/1 or less(21) and that the American
Heart Association(10,19,58,59) recommends water containing more than 20-22
mg/1 of sodium  (59 mg/1 sodium chloride) should not be used when patients
are on diets with an intake of sodium restricted to less than 1,000 mg/
day(59).  The normal adult intake of sodium is about 4,000 mg/day(10).
     Other specific cases of water supply contamination in Massachusetts
merit attention.  The Town of Becket in 1951 found the water in one of
its wells had drastically increased in chloride content to about 1,360
mg/1 attributable to a salt storage pile located uphill from the well(54).
Private and public water supplies in the Weymouth, Braintree, Randolph,
Holbrook, Auburn, and Springfield areas were among those believed to be
affected by highway salts, in Massachusetts.  Large salt storage piles
located at Routes 128 and 28 in Randolph, and located alongside the Blue
Hill River, were suspected of introducing contamination into Great Pond,
which serves as water supply for Braintree, Randolph, and Holbrook.  Water
supplies in Tyngsboro and Charlton were similarly experiencing salt in-
creases, and two wells in Charlton were likely to be abandoned(55).  Also,
in the general Boston area, snow removal and disposal practices are cited
as- contributing to heavy salt content in the Mystic Lakes(56).
     On the subject of industrial water use, Schraufnagel(12,49) found
that chlorides have been responsible for the corrosion of various metals
including stainless steels.  Schraufnagel also cites an industry state-
ment that "increasing the salinity average above the then 40 to 50 mg/1,
or lengthening the periods of high salinity, would increase corrosion of
all metals used in the handling system".  McKee and Wolf in 1963(60), in
their extensive review of the literature summarized chloride tolerances
for various industries as follows:  food canning and freezing - 760 mg/1;
carbonated beverages, food equipment washing, and paper manufacturing
(Kraft)  - 200 to 250 mg/1; steel manufacturing - 175 mg/1;  textiles,
brewing, and paper manufacturing (soda and sulfate pulp) - 60 to 100 mg/1;
and dairy processing, photography and sugar production - 20 to 30 mg/1(10,
60).  Other reviews on water quality needs for industry including chloride
limits are also available(61,62).

                                 33

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Vehicular and Roadway Damage

     Road salts not only promote vehicular corrosion, but may also affect
structural steel, house sidings, and other property(6,49,63-73).   It has
been previously estimated that the private car owner pays for corrosion
in the amount of about $100 per year(65).  Deicers may cause appreciable
damage to highway structures and pavements, particularly those constructed
of Portland cement(6,69,70).  Even though air-entrained concrete is re-
ported superior to non air-entrained concrete in its resistance to salts,
it is preferrable that neither form be exposed to road salts for at least
one year, after being poured(6,69,70).  Detrimental effects from deicing
salts have been reported(49,73) on various underground utilities, such
as cables and water mains.

Soil, Vegetation, and Trees

     Widespread damage of roadside soils, vegetation, and trees has been
observed where there has been liberal application of road salts(10,32,46,
74-109).  Most studies dealing with plant injury and death have focused
on the sugar maple decline(10,87-93,95-98,109) which has occurred over a
16-State area, mostly in the New England States.  Figures 25 through 28
resulting from a study conducted by the Connecticut State Highway Depart-
ment (95-98,109) show the progressive deterioration of sugar maples and
associated leaf damage.  Figure 25 taken in 1960 depicts the condition of
sugar maples on two sides of a road where longitudinal drainage is from
right to left.  Figure 26 depicts the condition of these maples five years
later.  Leaf margin burn, limb die-back, and varying degrees of defolia-
tion are pronounced on the trees on the left receiving the impact from
salt-laden drainage.  These effects are more readily illustrated by Fig-
ures 27 and 28.  The tree in Figure 27 on the left side of the roadway
shows severe stages of deterioration, and the leaves in Figure 28 demon-
strate severe leaf-margin burn.  It is important to realize here, in
general that until the 1960's, highway maintenance departments princip-
ally relied on abrasives as opposed to salt(3).

                                  34

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             FIGURE 25
  Relatively healthy Sugar Maples,
Photographed 1960, Route 17, Durham-
       Mi ddletown line, Conn.
              FIGURE  26
    Same trees as above - those on
      left exhibiting salt damage
           photographed 1965
                                       Courtesy of E. F. Butto
                                        State of Conn. Dept. o-
                                            Transportation
                 35

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            FIGURE 27
Close-up of Sugar Maple  exhibiting
   pronounced damage,  Route  17,
   Durham-Middietown line, Conn.
              FIGURE 28
 Healthy (right)  vs.
 Maple leaves,  from
  side of Route 17,
  Durham-Middletown
 damaged Sugar
right and left
respectively,
line, Conn.
Courtesy of E.  F.  Button,
 State of Conn.  Dept.  of
     Transportation
                 36

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     Tables VII through XI give relative salt tolerances of various fruit

crops, vegetable crops, field crops, grasses, forage legumes, trees, and

ornamentals.  It is hoped that this information may be used by highway

authorities and others in selecting roadside plants and vegetation.


                               TABLE VII

                     SALT TOLERANCE OF FRUIT CROPS—
                           Moderately
 Tolerant                   Tolerant                   Sensitive

 Date palm                 Pomegranate                 Pear
                           Fig                         Apple
                           Olive                       Orange
                           Grape                       Grapefruit
                           Cantaloup                   Prune
                                                       Plum
                                                       Almond
                                                       Apricot
                                                       Peach
                                                       Strawberry
                                                       Lemon
                                                       Avacado
 I/ Original Source, Bernstein, L.,  1965(101)
                                 37

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                           TABLE VIII

                                                2/
               SALT TOLERANCE OF VEGETABLE CROPS—
                          Moderately
Tolerant                   Tolerant                    Sensitive

Garden beet               Tomato                       Radish
Kale                      Broccoli                     Celery
Asparagus                 Cabbage                      Green bean
Spinach                   Caulifower
                          Lettuce
                          Sweet corn
                          Potato
                          Sweet potato-yam
                          Bell pepper
                          Carrot
                          Onion
                          Pea
                          Squash
                          Cucumber
2/ Original Source, Bernstein, L.,  1959(102).
                            TABLE IX

                 SALT TOLERANCE OF FIELD CROPS—

                          Moderately
Tolerant                   Tolerant                    Sensitive
Barley                    Rye                          Field bean
Sugar beet                Wheat
Rape                      Oats
Cotton                    Sorghum
                          Sorgo  (sugar)
                          Soybean
                          Sesbania
                          Broadbean
                          Corn
                          Rice
                          Flax
                          Sunflower
                          Castorbean
3/ Orignial Source, Bernstein, L., 1960(103)
                                38

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                            TABLE X
                                                     4/
         SALT TOLERANCE OF GRASSES AND FORAGE LEGUMES-
    Tolerant

Alkali sacaton
Saltgrass
Nuttall alkali-grass
Bermuda grass
Tall wheatgrass
Rhodes grass
Rescue grass
Canada wildrye
Western wheatgrass
Tall fescue
Barley
Birdsfoot trefoil
   Moderately
    Tolerant
Sensitive
White sweet clover     White dutch clover
 Yellow sweet clover            Meadow foxtail
 Perennial ryegrass Alsike clover
 Mountain brome     Red clover
 Harding grass      Ladino clover
 Beardless wildrye  Burnet
 Strawberry clover
 Dallis grass
 Sudan grass
 Hubam clover
 Alfalfa
 Rye
 Wheat
 Oats
 Orchard grass
 Blue gamma
 Meadow fescue
 Reed canary
 Big trefoil
 Smooth brome
 Tall meadow oatgrass
 Milvetch
 Sourclover
4/ Original Source, Bernstein, L., 1958(104)
                                39

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                                 TABLE XI
                                                       5/
                SALT TOLERANCE OF TREES AND ORNAMENTALS—
   Tolerant

Common matrimony vine
Oleander
Bottlebrush
White acacia
English oak
Silver poplar
Gray poplar
Black locust
Honey locust
Osier willow
White poplar
Scotch elm
Russian olive
Squaw bush
Tamarix
Hawthorne
Red oak
White oak
Apricot
Mulberry
  Moderately
   Tolerant

Silver buffalo berry
Arbor vitae
Spreading juniper
Lantona
Golden willow
Ponderosa pine
Green ash
Eastern red cedar
Japanese honey suckle
Boxelder maple
Siberian crab
European black currant
Pyracantha
Pittosporum
Xylosma
Texas privet
Blue spruce
Douglas fir
Balsam fir
White spruce
Beech
Cotton wood
Aspen
Birch
     Poorly
    Tolerant

Black walnut
Little leaf linden
Barberry
Winged euonymus
Multiflora rose
Spiraea
Artie blue willow
Viburnum
Pineapple guava
Rose
European hornbeam
European beech
Italian poplar
Black alder
Larch
Sycamore maple
Speckled alder
Lombardy poplar
Red maple
Sugar maple
Compact boxwood
Filbert
 5/ From  Zelazny, L.,  1968(100).
                                     40

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                             SECTION VIII
                            REFERENCES
 1.  "Highway Snow and Ice Control:  A Search for Innovative Tech-
     nological Alternatives", EPA Contract No. 68-01-0706, Abt Assoc.,
     Inc., Reports for EPA (1972).

 2.  "Study of the Environmental Impact of Highway Deicing", EPA Con-
     tract No. 68-03-0154, Arthur D. Little, Inc. (1972).

 3.  "Environmental Impact of Highway Deicing", 11040 GKK 06/71, Storm
     and Combined Sewer Technology Branch, Edison Water Quality Research
     Laboratory, EPA (June 1971).

 4.  "Survey of Salt, Calcium Chloride and Abrasive Use for Street and
     Highway Deicing in the United States and in Canada for 1966-1967",
     The Salt Institute, Alexandria, Virginia (date not given).

 5.  "Survey of Salt Calcium Chloride and Abrasive Use in the United
     States and Canada for 1969-1970", The Salt Institute, Alexandria,
     Virginia (date not given).

 6.  "Legislative Research Council Report Relative to the Use and Effects
     of Highway Deicing Salts", The Commonwealth of Massachusetts (Jan-
     uary 1965).

 7.  "The Encyclopedia of Oceanography", Encyclopedia of Earth Sciences
     by Fairbridge, R.W., Reinhold Publishing Company, New York, N.Y.
     (1966).

 8.  "Chemical Oceanography 1", Edited by Riley, J.P. and S. Kirrow, G.,
     Academic Press, London and New York  (1965).

 9.  Harvey, H.W., "The Chemistry and Fertility of Sea Waters", Cambridge
     at the University Press, London and New York (1963).

10.  Hanes, R.E., et. al., "Effects of Deicing Salts on Water Quality
     and Biota-Literature Review and Recommended Research", National Co-
     operative Highway Research Program Report 91, Virginia Polytechnic
     Institute and Highway Research Board (1970).

11.  Hutchinson, F.E.,  Personal communication (May 1970).

12.  Schraufnagel, F.M., "Chlorides", Commission on Water Pollution,
     Madison, Wisconsin (1965).
                                  41

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13.  "Mayor Sees Demonstration of New Salt Spreader", New York Times
     newspaper article (November 26, 1970) .

14.  "Mayor Inspects Cleanup Arsenal", New York Times newspaper article
     (October 24, 1970).

15.  "Highway Research Record Report No. 193 on Environmental Considera-
     tions in the Use of Deicing Chemicals", Foreword, Highway Research
     Board, Washington,  D.C. (1967).

16.  Greene, W.C., "What are the Problems",  Paper presented at the Univer-
     sity of Connecticut Symposium - Pollutants in the Roadside Environ-
     ment  (February 29,  1968).

17.  Burling, Jr., William H.,  Personal communications (August 1972).

18.  "Salt Contamination of Existing Well Supplies", Whitman and Howard,
     Inc., Report for Town of Burlington, Mass. (October 1971).

19.  Huling, E.E., and Hollocher, T.C., "Groundwater Contamination by Road
     Salt:  Steady-State Concentrations in East Central Massachusetts",
     Science, 176, 288 (April 21, 1972).

20.  "Public Health Service Drinking Water Standards - 1962", Public Health
     Service Publication No. 956, U.S. Department of Health, Education and
     Welfare, U.S. Government Printing Office, Washington, D.C. (1962) .

21.  "Water Quality Criteria",  National Technical Advisory Committee to
     the Secretary of the Interior, Washington, D.C.  (1968) .

22.  "Storing Road Deicing Salt", The Salt Institute, Alexandria, Virginia
     (1967).

23.  "The Snowfighter's Salt Storage Handbook", The Salt Institute, Alex-
     andria, Virginia (1968).

24.  Fitzpatrick, J.R.,  "Beehives Protect Snow-Removal Salt and Prevent
     Water Pollution",  American City  (September 1970).

25..  Members of the Milwaukee Sewerage Commission and Jones Island sewage
     treatment plant personnel,  Personal communication  (May 1970).

26.  Sullivan, R.H., "Effects on Winter Storm Runoff of Vegetation and as
     a Factor in Stream Pollution",  Paper presented at the Seventh Annual
     Snow Conference, Milwaukee, Wisconsin  (April 12, 1967).

27.  "Water Pollution Aspects of Urban Runoff", 11030 DNS 01/69, Contract
     No. WA 66-23, American Public Works Association, Report for U.S. EPA
     (January 1969).


                                   42

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28.  "Rainfall-Runoff and Combined Sewer Overflow",  Contract No. 14-12-402,
     Henningson, Durham and Richardson, Inc., Final Draft Report for U.S.
     EPA (March 1970).

29.  Hawkins, R.H., "Street Salting and Water Quality in Meadow Brook,
     Syracuse, New York",  Paper presented at the Street Salting Urban
     Water Quality Workshop, SUNY Water Resources Center, Syracuse Univer-
     sity,  Syracuse, N.Y. (May 6, 1971).

30.  Soderlund, G., et. al., "Physicochemical and Microbiological Proper-
     ties of Urban Stormwater Runoff",   Paper presented at the Fifth
     International Water Pollution Research Conference, San Francisco,
     California (July-August 1970).

31.  Hutchinson, F.E., "The Influence of Salts Applied to Highways on the
     Levels of Sodium and Chloride Ions Present in Water and Soil Samples",
     Project No. R1086-8, Progress Report No. II (July 1, 1966-June 30,
     1967).

32.  Hutchinson, F.E., "Effect of Highway Salting on the Concentration of
     Sodium and Chloride in Private Water Supplies",  Research in the Life
     Sciences (Fall 1969).

33.  Judd,  J.H., "Effect of Salt Runoff from Street Deicing on a Small
     Lake", Thesis submission - University of Wisconsin, Madison, Wiscon-
     sin (1969).

34.  Diment, W.H.  and Bubeck, R.C., "Runoff of Deicing Salt:  Effect on
     Irondequoit Bay, Rochester, New York", Paper presented at the Street
     Salting Urban Water Quality Workshop, SUNY Water Resources Center,
     Syracuse University, Syracuse, N.Y. (May 6, 1971).

35.  Ownbey, C.R.  and Kee, D.A., "Chlorides in Lake Erie", Tenth Con-
     ference Great Lakes Research, First Meeting International Associa-
     tion of Great Lakes Research, Toronto, Canada (April 1967).

36.  Keup,  L.E., Personal communication (1971).

37.  Sharp, R.W.,  "Road Salt as a Polluting Element", Special Environ-
     mental Release No. 3, Bureau of Sport Fisheries and Wildlife, U.S.
     Department of Interior  (December 14,  1970).

38.  Feick, G.,  et. al., "Release of Mercury from Contaminated Freshwater
     Sediments by the Runoff of Road Deicing Salt", Science, 175, 1142
     (March 10,  1972).

39.  Smith, H.A.,  "Progress  Report on NCHRP Project 16-1; Effects of
     Deicing Compounds on Vegetation and Water Supplies", Paper pre-
     sented at the 54th Annual Meeting of the American Association of
     State  Highway Officials, Minneapolis, Minnesota (December 5, 1968).


                                  43

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40.  "Toxicity and Pollution Study of Carguard Chemicals, 1965-1966",
     Cargill, Inc., Minneapolis, Minnesota.

41.  Materials in the Files of the Storm and Combined Sewer Technology
     Branch, Edison Water Quality Research Laboratory, U.S. EPA (1970).

42.  "Salt Buildup in Drinking Water a Danger to Some Bay Staters",
     Boston Globe newspaper article (May 8,  1970).

43.  Deutsch, M., "Ground Water Contamination and Legal Controls in Michi-
     igan", Water Supply Paper No. 1691, USGS (1963).

44.  Walker, W.H., "Salt Piling - A Source of Water Supply Pollution",
     Pollution Engineering, 2_, 3  (July-August 1970).

45.  Hutchinson, F.E., "The Influence of Salts Applied to Highways on the
     Levels of Sodium and Chloride Ions Present in Water and Soil Samples",
     Project No. R1086-8, Progress Report No. I (July 1, 1965-June 30,
     1966).

46.  Hutchinson, F.E., "The Influence of Sodium and Chloride Ions Present
     in Water and Soil Samples", Project No. R1088-8, Progress Report No.
     Ill  (1968).

47.  Smith, R.D., "The Groundwater Resources of Summit County, Ohio",
     Ohio Division of Water, Bulletin No. 27 (1953).

48.  Rahn, P.H., "Movement of Dissolved Salts in Groundwater Systems",
     Paper presented at the University of Connecticut Symposium-Pollutants
     in the Roadside Environment  (February 29,  1968).

49.  Schraufnagel, F.M., "Pollution Aspects Associated with Chemical
     Deicing", Highway Research Record Report No.  193, HRB, Washington,
     D.C. (1967).

50.  U.S. Geological Survey, Personal communication (May 1970).

51.  Scheldt, M.E., "Environmental Effects of Highways", Journal of the
     Sanitary Engineering Division, Proceedings of the American Society
     of Civil Engineers, 93, No. SA5, Paper No. 5509  (October 1967).

52.  "Side Effects of Salting for Ice Control", American City, 80,
     (August 1965).

53.  "Salting Highways Could Contaminate Ground Water", Reclamation News
     (April 1965) .

54.  "Road Salt Blamed for Souring Water", Boston Globe newspaper article
     (April 1970) .
                                   44

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55.  "Do Road Salts Poison Water Supplies?", Boston Globe newspaper
     article (1968 or 1969).

56.  "Alewife Brook Polluted", Boston Globe newspaper article (May 1970).

57.  "The Massachusetts Department of Public Health last year warned 62
     communities in the Bay State that the sodium content in their drink-
     ing water was high enough to pose a health hazard to people on low
     salt diets", Boston Globe newspaper article, Section 1, p.  2, (Aug-
     ust 1, 1971).

58.  "Your 500-Milligram Sodium Diet", The American Heart Association
     (1957).

59.  "Your 1000-Milligram Sodium Diet", The American Heart Association
     (1957) .

60.  McKee, J.E., and Wolf,  H.W., "Water Quality Criteria", Second
     Edition, State Water Quality Control Board, Sacramento, Calif.
     (1963) .

61.  Moore, E.W., "Tolerable Salt Concentrations in Drinking Waters",
     Progress Report to the Sub-committee on Water Supply of the Com-
     mittee on Sanitary Engineering and Environment (1950).

62.  "Manual on Industrial Water", Spec. Tech. Pub. No. 148, ASTM,
     Committee D-19 on Industrial Water (1953).

63.  Lockwood, R.K., "Snow Removal and Ice Control in Urban Areas",
     Research Project No. 114, Volume I, American Public Works Associa-
     tion  (August 1965).

64.  Kallen, H.P., "Corrosion", Special Report, Power (December 1956).

65.  "What is Highway Salt Doing to Us?", Milwaukee Journal newspaper
     article (May 4, 1970).

66.  "Report Discusses Salt Corrosion", APWA Reporter (October 1970).

67.  Article appearing in Automotive Industries  (February 1, 1964).

68.  Article appearing in Steel  (March 2, 1964).

69.  "U.S. Highway Research Board Bulletin No. 323", Washington, D.C.
     (1962).

70.  Dickinson, W.E., "Publication No. 98", National Ready Mixed Con-
     crete Association, Washington, D.C.  (1961).

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71.  "The Elimination of Pavement Sealing By Use of Air Entraining
     Portland Cement", HB 18.8,  Portland Cement Association,  Chicago,
     Illinois.

72.  "Protection of Existing Concrete Pavements from Salt and Calcium
     Chloride", HB 1-2, Portland Cement Assoication, Chicago, 111.

73.  Hamman, W. and Mantes,  A.J., "Corrosive Effects of Deicing Salts",
     Journal American Water  Works Association,  58,  11 (November 1966) .

74.  Hutchinson, F.E., "The  Influence of Salts  Applied to Highways on
     the Levels of Sodium and Chloride Ions Present in Water and Soil
     Samples", Project No. A-007-ME, Project Completion Report (July
     1965-June 1969).

75.  Roberts, E.G., and Zybura,  E.L., "Effect of Sodium Chloride on
     Grasses for Roadside Use",  Highway Research Record Report No.
     193, HRB, Washington, D.C.  (1967).

76.  Prior, G.A., "Salt Migration in Soil", Paper presented at the
     University of Connecticut Symposium - Pollutants in the Roadside
     Environment (February 29, 1968).

77.  Prior, G.A. and Berthouex,  P.M., "A Study  of Salt Pollution of
     Soil by Highway Salting", Highway Research Record Report No.
     193, HRB, Washington, D.C.  (1967).

78.  Hutchinson, F.E. and Olson, B.E., "The Relationship of Road Salt
     Applications to Sodium  and Chloride Ion Levels in the Soil Border-
     ing Major Highways", Highway Research Record Report No.  193, HRB,
     Washington, D.C.  (1967).

79.  Thomas Jr., L.K., "Notes on Winter Road Salting (Sodium Chloride)
     and Vegetation", Scientific Report No. 3,  National Park Service
     (March 31, 1965).

80.  Hutchinson, F.E., "The  Relationship of Road Salt Applications to
     Sodium and Chloride Ion Levels in the Soil Bordering Major High-
     ways", Paper presented  at the University of Connecticut Symposium -
     Pollutants in the Roadside Environment (February 29, 1968).

81.  Thomas Jr., L,K., and Bean, G.A., "Winter  Rock Salt Injury to
     Turf  (Poa pratenais L.)", Scientific Report No. 5, National Park
     Service  (August 23, 1965).

82.  Wester, H.V. and Cohen, E.E., "Salt Damage to Vegetation in the
     Washington, D.C. Area During the 1966-1967 Winter", Plant Disease
     Reporter, 52, 5  (May 1968).
                                   46

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83.  Thomas Jr., L.K., "A Quantitative Microchemical Method for Deter-
     mining Sodium Chloride Injury to Plants", Scientific Report No.
     4, National Park Service  (1965).

84.  Roberts, E.G., "Effect of Deicing Chemicals on Grassy Plants",
     Paper presented at the University of Connecticut Symposium -
     Pollutants in the Roadside Environment (February 29, 1968).

85.  Verghese, K.G., et. al., "Sodium Chloride Uptake and Distribution
     in Grasses as Influenced by Fertility Interaction and Complementary
     Anion Competition", Unpublished Report, Virginia Polytechnic
     Institute  (1969).

86.  French, D.W., "Boulevard Trees are Damaged by Salt Applied to
     Streets", Minnesota Farm and Home Science, XVI, 2, 9 (1959).

87.  LaCasse, N.L., "Maple Decline in New Hampshire", M.S. Thesis,
     University of New Hampshire (1963).

88.  LaCasse, N.L., and Rich, A.E., "Maple Decline in New Hampshire",
     Phytopathology, 54 (1964) .

89.  Rich, A.E., and LaCasse, N.L., "Salt Injury to Roadside Trees",
     Forest Notes (Winter 1963-1964).

90.  Rich, A.E., "Effect of Deicing Chemicals on Woody Plants", Paper
     presented at the University of Connecticut Symposium - Pollutants
     in the Roadside Environment (February 29, 1968).

91.  Kotheimer, J., Niblett, C., and Rich, A.E., "Salt Injury to Road-
     side Trees - A Progress Report", Forest Notes, 85, 3-4 (1965).

92.  Westing, A.H., "Sugar Maple Decline:  An Evaluation", Botany,
     20_, 2 (1966) .

93.  Holmes, F.W.  and Baker, J.H.,  "Salt Injury to Trees, II.  Sodium
     and Chloride in Roadside Sugar Maples in Massachusetts",  Phyto-
     pathology, 56, 6 (June 1966).

94.  Zelazny, L.W., et.  al., "Effects of Deicing Salts on Roadside
     Soils and Vegetation, II. Effects on Silver Maples (Acre sac-
     charinum L.)", Unpublished Report, Virginia Polytechnic Institute
     (1970).

95.  Button, E.F.  and Peaslee, D.E., Unpublished data from Connecticut
     State Highway Department, Department of Research and Development
     and Connecticut Agricultural Experiment Station.

96.  Button, E.F., "Influence of Rock Salt Used for Highway Ice Control
     on Natural Sugar Maples at One Location in Central Connecticut",
     Report No. 3, Connecticut State Highway Department (1964).
                                   47

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 97.  Button, E.F., "Influence of Rock Salt, Salt Used for Highway Ice
      Control on Natural Sugar Maples at One Location in Central Connect-
      icut", Report No. 3A, Connecticut State Highway Department (1964).

 98.  Button, E.F., "Ice Control Chlorides and Tree Damage", Public
      Works, 93_, 3 (1965).

 99.  Allison, L.E.,  "Salinity in Relation to Irrigation", Advances in
      Agronomy, 16 (1964).

100.  Zelazny, L.W.,  "Salt Tolerance of Roadside Vegetation", Paper pre-
      sented at the University of Connecticut Symposium - Pollutants
      in the Roadside Environment (February 29, 1968).

101.  Berstein, L. "Salt Tolerance of Fruit Crops", Department of
      Agriculture Bulletin No. 292 (1965).

102.  Bernstein, L.,  "Salt Tolerance of Vegetable Crops in the West",
      Department of Agriculture Bulletin No. 205 (1959).

103.  Bernstein, L.,  "Salt Tolerance of Field Crops", Department of
      Agriculture Bulletin No. 217 (1960).

104.  Bernstein, L.,  "Salt Tolerance of Grasses and Forage Legumes",
      Department of Agriculture Bulletin No. 194 (1958) .

105.  Monk, R.W., and Peterson, H.B., "Tolerance of Some Trees and
      Shrubs to Saline Conditions", Proc. American Soc. Hort. Sci., 81
      (1962) .

106.  Rudolfs, W., "Influence of Sodium Chloride Upon the Physiological
      Changes of Living Trees", Soil Science 8^  (1919).

107.  Strong, F.C., "A Study of Calcium Chloride Injury to Roadside
      Trees", Michigan Agr. Exp. Sta. Quart. Bull., 27^ (1944).

108.  Sauer, G., "Damage by Deicing Salts to Plantings Along the Federal
      Highways", News Journal, German Plant Protective Service, 19, 6
      (1967).

109.  Button, E.F., Personal communication  (August 1972).
                                   48

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SELECTED WATER
RESOURCES ABSTRACTS
INPUT TRANSACTION FORM
/. Report No,
 EPA-R2-
 73-257
w
    Water Pollution and Associated Effects from
    Street Salting
                    5.  Kepor' J' : ors gnvironmentaj  damages,  hydrophobic  substances,  highway deicing,  groundwater
     contamination, plant tolerances,  public water supplies,  salt  storage,  vehicular
     corrosion, water pollution effects, wintertime highway  runoff, snow removal
     practices.

i~b. Identifiers Stormwater Runoff
                                                    Send To:
                                                    WATER RESOURCES SCIENTIFIC INFORMATION CENTER
                                                    US DEPARTMENT OF THE INTERIOR
                                                    WASHINGTON. D C 2O24O
         Richard Field
 USEPA/EWQRL, Edison, New Jersey  08817

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