&EPA
             United States
             Environmental Protection
             Agency
             Environmental Monitoring
             Systems Laboratory
             P.O. Box 93478
             Las Vegas NV 89193-3478
EPA/600/4-89/045A
November 1989
             Research and Development
Proximity of Delaware
Sanitary Landfills
to Wetlands and
Deep water Habitats
             Statewide Results

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                                               EPA 600/4-89/045A
                                               November 1989
        OF DELAWARE SANITARY LANDFILLS  TO  WETLANDS AND
                 DEEPWATER HABITATS
                  Statewide Results
                         by

                  Robin L. Gebhard
             National Wetlands Inventory
           U.S. Fish  and Wildlife Service
            St.  Petersburg,  Florida 33702

         Roy C.  Herndon and John E.  Moerlins
Center for Biomedical  and Toxicological  Research and
            • Hazardous Waste Management
              Florida  State University
           Tallahassee, Florida 32306-4016

                         and

                  Victor W. Lambou
     Environmental Monitoring Systems Laboratory
        U.S. Environmental Protection Agency
            Las Vegas, Nevada  89193-3478
    ENVIRONMENTAL MONITORING SYSTEMS LABORATORY
         OFFICE OF RESEARCH AND DEVELOPMENT
        U.S. ENVIRONMENTAL PROTECTION AGENCY
               LAS VEGAS,  NEVADA 89114

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                           NOTICE
The information  in  this document has been  funded  wholly or
in part  by the  U.S.  Environmental Protection  Agency  under
Grant No.  CR-815139010  to  the Florida State University.   It
has been subject to  the  Agency's  peer  and administrative
review and it has been  approved for publication  as an  EPA
document.   Mention of  trade  names  or  commercial products
does not constitute endorsement or recommendation for use.
                            11

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                          ABSTRACT
     Sanitary  landfills  can  cause  considerable  harm  to
sensitive  ecosystems  if  they  are not  properly  located,
designed,  and  managed.   The purpose of  this report  is  to
summarize  the  proximity of  sanitary landfills  in the state
of  Delaware  to  wetlands   and  deepwater  habitats   (i.e.,
rivers,  lakes,   streams,  bays,  etc.);  a companion  report
presents data  on individual landfills.    The  source  of data
used to  determine the  locations of the  sanitary landfills
was the computer data file developed by Development Planning
and  Research   Associates,   Inc.   for   use  by   the  U.S.
Environmental Protection  Agency's  Office  of  Solid Waste  in
its RCRA  Subtitle  D program.    The sanitary  landfills were
identified  on  U.S.  Fish  and  Wildlife   Service's  National
Wetlands Inventory  maps.   The nearness or proximity  of the
sanitary  landfills  to  wetlands  and deepwater  habitats  was
determined  by  drawing  three concentric   regions  around  the
point representing the location of each landfill.  The radii
of the  concentric regions were: 1/4 mile,  1/2 mile,  and 1
mile.  All sanitary landfills in the state of Delaware are
located  in or  are close  to either wetlands or deepwater
habitats.   These  facilities  have the potential to adversely
affect sensitive ecosystems, such as wetlands and deepwater
habitats,  either through  habitat alterations  or through the
migration  of contaminants from sanitary landfills.
                            111

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                       CONTENTS
Abstract	iii
Figures	v
Tables	vi
     Introduction	1
     Conclusions	1
     Materials and Methods	2
     Results and Discussion	5
Literature Cited	7
                            iv

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                       FIGURES
Number                                                  Page

1    Hypothetical sanitary landfill showing the point
         (latitude  and  longitude  coordinates)  that
        represents the  location  of the landfill,  the
        concentric  regions  used  to  determine  the
        nearness   or   proximity   of  the   sanitary
        landfill to  wetlands  and deepwater habitats,
        and  the  boundary  of an  100-acre  sanitary
        landfill   distributed  approximately  evenly
        around   its   point   location   (a   100-acre
        landfill uniformly distributed around a point
        will  have  a   radius  of  approximately  1/4
        mile).                                              8

2    Proximity  of 3  Delaware sanitary  landfills  to
        wetlands-                                           9

3    Distance of 3 Delaware sanitary landfills to the
        closest wetland.                                  10

4    Proximity  of 3  Delaware sanitary  landfills  to
        deepwater habitats.                                11

5    Distance of 3 Delaware sanitary landfills to the
        closest deepwater habitat.                         12

6    Proximity  of 3  Delaware sanitary  landfills  to
        either  the   closest   wetland  or  deepwater
        habitat.                                          13

7    Distance  of  3  Delaware  sanitary  landfills  to
        either  the   closest   wetland  or  deepwater
        habitat.                                          14

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                        TABLES
Number                                                  Page

1    Definition of wetlands used by the U.S. Fish and
        Wildlife Service                                  15

2    Definition  of deepwater  habitats  used by  the
        U.S. Fish and Wildlife Service                    17

3    Definitions of  the five  major systems  used  by
        the  U.S.   Fish  and  Wildlife   Service   in
        classifying wetlands and deepwater habitats       18

4    Number and  percentage of sanitary  landfills  in
        Delaware that are proximate to wetlands           23

5    Number and  percentage of sanitary  landfills  in
        Delaware  that  are  proximate  to  deepwater
        habitats                                          24

6    Number and  percentage of sanitary  landfills  in
        Delaware   that   are   proximate  to   either
        wetlands or deepwater habitats                    25
                           VI

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                         INTRODUCTION

     Sanitary  landfills,  as  typically  defined,  are  waste
management  facilities  regulated under  Subtitle D of  the
Resource  Conservation   and  Hecovexy  Act   (RCKA).     These
facilities  are  commonly  referred  to  as  municipal  waste
landfills and  they are  primarily used to  receive household
refuse and nonhazardous  commercial waste.  However,  sanitary
landfills also receive other types of  Subtitle D waste, such
as sewage sludge  and industrial wastes.   Sanitary landfills
typically  receive  some  hazardous   waste  in  the  form  of
household hazardous waste, and hazardous  waste  from  small
quantity  generators  as defined  in  40  CFR  Part  261.10
(Definitions).  Depending upon  the  definition  of a  sanitary
landfill  used  by  the  individual states, there  are between
6,500 and 9,300 of these facilities permitted  in the United
States (U.S. EPA,  1987).

     Sanitary  landfills can   cause   considerable  harm  to
sensitive  ecosystems  if  they   are not  properly  located,
designed, and managed.   These  facilities have  the potential
to adversely  affect sensitive  ecosystems,  such  as  wetlands
and deepwater  habitats,   either  through  habitat  alterations
or  through  the  migration of   contaminants  from  sanitary
landfills.   In order  to  evaluate  the seriousness  of this
problem,   information  is  needed on the nearness  of  sanitary
landfills to wetlands and surface water bodies.  The purpose
of  this   study  is  to document the proximity of  sanitary
landfills in the state of Delaware to wetlands  and deepwater
habitats  (i.e.,  rivers,   lakes,  streams,  bays,  etc.).   This
report gives statewide summary  results;  a  companion report,
"Proximity  of  Delaware  Sanitary Landfills  to Wetlands  and
Deepwater Habitats,  Data on  Individual Landfills,"  presents
data on the individual landfills.
                           CONCLUSIONS
1.   All  sanitary landfills  in the  state  of Delaware  are
     located in or are close to either wetlands or deepwater
     habitats.

2.   These facilities have the potential to adversely affect
     sensitive  ecosystems,  such  as  wetlands  and  deepwater
     habitats, either through habitat alterations or through
     the migration of contaminants from sanitary landfills.

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                    MATERIALS AND METHODS
     The source  of data used to  determine  the locations of
the sanitary  landfills  was  the computer data file developed
by Development Planning and Research Associates, Inc.  (DPRA)
for use by the U.S. Environmental Protection Agency's Office
of Solid Waste  in its RCRA Subtitle D program  (DPRA, 1986).
The DPRA  data  file  includes  information on  1,683 sanitary
landfills, and  6,849 of these  facilities have latitude and
longitude  coordinates  in  degrees,  minutes,  and  seconds
specified in  the  data file.  Each set of coordinates defines
a  point  which  represents the  geographic  location  of  a
sanitary  landfill (Figure 1) .   In addition,  the  data file
contains the  names of the landfills and data on the cities
or  counties  in  which  the  landfills  reside.    Individual
states  are  responsible for  permitting sanitary  landfills
under  Subtitle  D  of  RCRA  and,  since DPRA  obtained  the
information  for  the data file  from state sources,  the site
location  information varies  in terms  of   accuracy  and the
point chosen  to represent the location  of  each facility.

     Four  types  of errors  or  omissions were  identified in
the DPRA  data  file.    These  errors and omissions include:
missing latitude and longitude,  missing state  code,  wrong
state code, and erroneous latitude/longitude.  The first two
items  relate to  data  that were  omitted  in  the  facility
record.  Facilities that did not have latitude and longitude
coordinates  were not used in  this study  while  facilities
that did not  have a state code were assigned an appropriate
state   code   by   comparing   the   latitude  and  longitude
coordinates  for  the  facilities  with  maps  of the  various
states.   The last  two  items   relate  to ' errors in  the data
file.   Facilities with  the wrong state code  were corrected
and  included  in  the  study.    The  last   item relates  to
erroneous   latitude  and/or   longitude  records.     Where
discovered,  the  erroneous coordinate(s) were  corrected,  if
possible.   Errors may  still  exist in  the  DPRA  data  file;
however,  it  is  believed  that  the  overall  results  and
conclusions   contained   in   this   report    will   not   be
significantly affected,  since  the  number  of  errors  is
probably small.

     Wetlands typically form part of a continuous transition
zone  between uplands  and  open  water.    Therefore,  the
delineation of the upper and lower boundaries in any wetland
definition  is somewhat  arbitrary.   There  are a  number of
definitions of wetlands that  have been  developed for use in
classifying natural environments or for regulatory purposes.
While  these   definitions  are  not  identical,  they  are very
similar.   The selection of a  specific definition for use in

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this  study was determined  by the  availability  of national
wetlands and deepwater habitats geographic data.
     The  most, extensive, consistent  source  of wetlands
deepwater  habitats  geographic data  is the  U.S.  Fish and
Wildlife  Service's National Wetlands  Inventory  (NWI) .   The
NWI  has   developed   detailed,   large-scale  maps   for  a
significant portion  of the  United States.   To date, wetland
maps have been developed for approximately 40 percent of the
contiguous  48  states,   10  percent  of Alaska,  and  all  of
Hawaii.   Large-scale NWI maps typically are either 1:24,000
scale  or  1:63,360  scale U.S. Geological  Survey quadrangle
maps;  however,  most  are  1:24,000  scale.    Wetlands  and
deepwater  habitats  are  delineated  on the  NWI  maps.   The
delineation of wetlands  and deepwater  habitats was developed
using  remote  sensing  techniques and  field investigations.
The NWI maps  are developed in accordance  with the National
Map  Accuracy  Standard  (NMAS)  (U.S.  GS,  1979).   The NWI
1:24,000  scale  maps  used  in  this   study  are  accurate,
according  to   the  NMAS,  to  within  40  feet  of  ground
measurements.    These   maps   are  particularly  useful  for
plotting  the   location  of   sanitary  landfills  and  for
determining the proximity  of these  facilities  to wetlands
and deepwater habitats .

     The NWI maps  use the definitions  (contained in Tables 1
and 2) and  the classification system  (contained in Table 3)
for wetlands  and  deepwater  habitats  developed by  the U.S.
Fish and Wildlife  Service (Cowardin  et al.,  1979).  Wetlands
are defined as  lands transitional  between  terrestrial and
aquatic systems  where the water  table is usually at or near
the  surface,   or  the  land  is  covered  by  shallow  water.
Deepwater habitats are defined as permanently flooded  lands
lying  below the deepwater  boundary of wetlands.   For more
expansive definitions and an explanation of the definitions,
as  well  as the boundary  limits,  see  Tables  1 and  2; for
further details  see Cowardin  et al.  (1979).   The U.S. Fish
and  Wildlife   Service's  classification  of  wetlands  and
deepwater habitats is hierarchical in  nature proceeding from
general to  specific  (Cowardin et  al., 1979).  There  are 5
systems,  10 subsystems,  and 55 classes.  In this study only
the  "system",  i.e,  the  complex  of wetlands  and deepwater
habitats  that  share  the influence  of  similar  hydrologic,
geomorphologic,  chemical, or  biological factors,  was  used
for classification purposes.   The definitions as well as the
boundary  limits  of   the   five  systems,   i.e.,   Marine,
Estuarine, Riverine,  Lacustrine,  and  Palustrine,  are given
in Table  3; for  further details  see Cowardin et al. (1979) .
The first  four systems,  i.e., Marine, Estuarine,  Riverine,
and Lacustrine, include  both wetlands  and deepwater habitats
whereas the Palustrine System  includes only wetlands.

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     In order  to link the location of sanitary landfills in
the DPRA  data  file to the appropriate NWI maps,  we used the
information on the T-70 computer tape obtained from the U.S.
Geological Survey  (National Cartographic  Information Center,
1987) .   The  NWI large-scale maps  were  developed using U.S.
Geological Survey's quadrangle maps  as  base maps.  The T-70
computer  tape  contains  67 fields of  information including
latitude  and longitude that  can be used for identifying the
1:24,000  scale  maps,  the map names,   and  the  state  codes
assigned  to  the maps.   Sanitary  landfill  location  data on
the  DPRA  computer  file  tape  were  matched  by  a  computer
program against  location data  on the US Geological Survey T-
70 computer tape in order  to identify the specific maps that
contain  sanitary  landfills and/or that would be needed to
evaluate  the wetlands  and  deepwater habitats that are within
1 mile  of each  sanitary landfill.   Sanitary landfills that
were located on  the edge  or  in the corner of a map required
more than one  map  (i.e.,  two  to  four maps)  to complete the
interpretation.  The  map  names obtained  from the  computer
matching  were  sorted by state and compared with  inventories
of available NWI maps.

     Each sanitary landfill  included  in   this  study  was
located on NWI  large-scale maps using standard cartographic
techniques;  Nearness or  proximity of sanitary landfills to
wetlands  and deepwater habitats  was determined  by  drawing
three concentric regions  around the point  representing the
location  of  each   landfill.    The radii  of  the  concentric
regions were:  1/4  mile,  1/2   mile,  and 1 mile   (Figure 1)  .
The occurrence or  nonoccurrence of the wetland and deepwater
habitat systems  in each concentric region was then recorded.

     Many sanitary landfills   are typically  of the  order of
100  acres in size.  For  example,  in  the  state  of  Florida
about  35  percent  of  the active  sanitary  landfills  are
between  50 and  150  acres  in size, with the average  size
being   110   acres   (Florida   Department   of  Environmental
Regulation, 1987) .   A  landfill that is 100 acres  in size and
uniformly distributed  about   its  latitude/longitude  point
designation  will  have  a   radius  of  approximately 1/4  mile
and, therefore,  will approximate the boundary of the  first
concentric 1/4-mile radius region  (Figure 1).  Undoubtedly,
most of the  landfills  located in a 1/4-mile  radius region
containing either  wetlands or deepwater  habitats should be
considered to be located  in  wetlands or deepwater habitats.
Since landfills  vary considerably  in size and shape,  some of
the  landfills   located in  the 1/2-mile  radius  and  1-mile
radius  regions  containing wetlands  or  deepwater  habitats
will  probably  also  be located  in wetlands or deepwater
habitats.  The  exact geographic boundary of the  landfill is
not  the  critical  consideration  for  determining  adverse
impacts associated with these  facilities, since contaminants

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can  migrate  off-site  to  affect  wetlands  and  deepwater
habitats.
                   RESULTS AND DISCUSSION
     We  obtained  data  on  the  proximity  of  3  sanitary
landfills in the state of Delaware to wetlands and deepwater
habitats.   There  are 3 sanitary  landfills  in  the DPRA data
file for the  state of Delaware  and  all of these facilities
have NWI maps available for site  interpretation.

     Approximately 67 percent  of the sanitary landfills are
located in or within 1/4 mile  of  wetlands, while 100 percent
are located in  or  within  1/2  mile of wetlands, (Table 4 and
Figure 2) .   None  of  the  landfills are  located  more  than a
mile from  any  type of wetland.   All  sanitary landfills are
located  either  in  or  are  close  to   Palustrine  wetlands
(approximately  33, and  100  percent  are located in or within
1/4, and 1/2,  respectively,  of a Palustrine wetland) .  None
of  the  sanitary  landfills  are  located more  than  1/2 mile
from a wetland  (Figure 3).

     Approximately 33  percent (1 facility)  of the sanitary
landfills  are   located  in  or  within  1/4 mile of deepwater
habitats, while 33 and 67 percent are  located in or within
1/2 and  1  mile  of deepwater habitats,  respectively (Table 5
and Figure 4).  One  (33 percent)  of the  landfills is located
more than  a mile  from  any  type  of  deepwater  habitat.   The
facilities  that  are  located in  or   that   are  close  to
deepwater  habitats  are in the  vicinity  of Estuarine  or
Riverine deepwater habitats  (i.e., 33 percent  are located in
or  within  1 mile  of a Estuarine deepwater habitat  and 67
percent  are  located in  or  within  1   mile  of  a  Riverine
deepwater  habitat).   Approximately  33  percent  are located
more than  1 mile  from the  closest deepwater habitat  (Figure
5) , while  33  percent  are  located  1/2  to  1  mile  from the
closest deepwater habitat.

     Approximately 67 percent  of the sanitary landfills are
located  in  or within  1/4   mile  of   either  wetlands  or
deepwater habitats,  while  all are located  in  or within 1/2
mile of  either wetlands or deepwater habitats (Table 6 and
Figure 6).   All of the sanitary landfills are  located either
in  or  are  close  to  Palustrine  habitats (approximately 33,
and 100 percent are  located in or within 1/4,  and 1/2 mile,
respectively, of a Palustrine  habitat)  while more than half
of the sanitary landfills are  located either in or are close
to Riverine habitats,  (approximately 33, 33,  and 67 percent
are located in  or within 1/4,  1/2, and 1 mile, respectively,
of a Riverine habitat).  None of the sanitary landfills are

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located  more  than   1/2  mile  from  either  a  wetland  or
deepwater habitat  (Figure 7).

     All of the sanitary landfills included in this study in
the state of  Delaware are  located either in or are close to
wetlands.  From this, we conclude that these facilities have
the potential to adversely affect sensitive ecosystems, such
as wetlands,  either through habitat  alterations  or through
the migration of contaminants from sanitary  landfills.   In
addition, two-thirds of the sanitary  landfills  included in
this study in the state of Delaware are located either in or
close to deepwater habitats and they also have the potential
for adversely affecting these sensitive ecosystems.

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                      LITERATURE CITED

Cowardin,  L.M.,   V.  Carter,  F.C.  Golet,   and E.T.  LaRoe.
     1979.     Classification  of   wetlands   anH   cieep«ater
     habitats of tne United States.  FWS/OBS-79/31.  103 pp.

Development  Planning and  Research Associates, Inc.   1986.
     U.S. Environmental  Protection Agency  list of municipal
     waste   landfills.       Computer    data   file,    U.S.
     Environmental Protection Agency.

Florida Department of Environmental Regulation.   1987.   CMS
     25 data file.   Computer data file,  Florida  Department
     of Environmental Regulation.

Langbein, W.B. and K.T.  Iseri.   1960.   General introduction
     and  hydrologic  definitions manual of  hydrology.   Part
     I.   General surface-water techniques.   US  Geol.  Surv.
     Water-Supply Paper  1541-A.  29 pp.

National  Cartographic  Information  Center.    1987.    T-70
     computer  tape.   Computer  data file,  National Mapping
     Division, U.S. Geological Survey.

U.S. EPA.   1987.    Resource  Conservation and Recovery Act
     Subtitle D  report to Congress.  Final Draft Report, May
     28,  1987.

U.S. GS.    1979.  Maps  for America,  First Edition.   U.S.
     Geological  Survey.

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        Point Representing
        Location of the
        Landfill
Hypothetical
Landfill
Boundaries
                               Lacustrine Deepwater Habitat
                  Palustrme Wetland
                        (marsh)
Rgure 1.  Hypothetical sanitary landfill showing the point (latitude and longitude coor-
          dinates) that represents the location of the landfill, the concentric regions used
          to determine the nearness or proximity of the sanitary landfill to wetlands and
          deepwater habitats, and the boundary of a 100-acre sanitary landfill distrib-
          uted approximately evenly around its point location (a 100-acre sanitary land-
          fill uniformly distriubted around a point will have a radius of approximately
          1/4 mile).

                                        8

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 Palustrine
 Lacustrine
   Riverine
  Estuarine
    Marine
All systems
In or within 1 mile





In or within 1/2 mile




In or within 1/4 mile
                                                               100
               120
                                     Percent
         Figure 2. Proximity of 3 Delaware sanitary landfills to wetlands.

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     >1mite
 1/2 to 1 mile
1/4 to 1/2 mile
     1/4 mile
            0          20         40         60          80          100
                                       Percent
    Figure 3. Distance of 3 Delaware sanitary landfills to the closest wetland.

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 Lacustrine
   Riverine
  Estuarine
    Marine
All systems
                                   40
          In or within 1 mile





          In or within 1/2 mile




          In or within 1/4 mile
60
80
100
                                       Percent
   Figure 4. Proximity of 3 Delaware sanitary landfills to deepwater habitats.

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        >1mite
    1/2to1 mile
   1/4 to 1/2 mile
      <, 1/4 mile
33
              0           20         40          60          80         100



                                         Percent
Figure 5. Distance of 3 Delaware sanitary landfills to the closest deepwater habitat.

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          Palustrine
         Lacustrine
           Riverine
          Estuarine
            Marine
         All systems
                             20        40
                In or within 1 mile





                In or within 1/2 mite




                In or within 1/4 mite
60
                                             Percent
100       120
Figure 6. Proximity of 3 Delaware sanitary landfills to either closest wetland or deepwater habitat.

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            >lmite
         1/2 to 1 mile
        1/4 to 1/2 mile
             1/4 mile
Figure 7. Distance of 3 Delaware sanitary landfills to either the closest wetland or deepwater habitat.

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  TABLE 1.  DEFINITION OF WETLANDS USED BY THE U.S. FISH AND
        WILDLIFE  SERVICE  FROM COWARDIN ET AL.  (1979)
Definition:
               Wetlands   are   lands   transitional  between
               terrestrial  and  aquatic  systems  where  the
               water  table  is usually  at  or near the surface
               or  the land  is covered  by  shallow water.   For
               purposes  of  this  classification wetlands must
               have   one  or  more  of  the following   three
               attributes:  (1)   at least  periodically/  the
               land  supports  predominantly hydrophytes;  (2)
               the  substrate   is  predominantly  undrained
               hydric soil; and  (3) the substrate  is nonsoil
               and is saturated with  water  or  covered by
               shallow water-at  some time during the growing
               season of each year.

Explanation:
               The term  wetland includes  a variety of  areas
               that  fall into  one of  five  categories:  (1)
               areas  with hydrophytes  and hydric soils, such
               as  those  commonly  known  as marshes,  swamps,
               and bogs; (2)  areas  without  hydrophytes  but
               with  hydric  soils-for  example,  flats   where
               drastic  fluctuation  in   water   level,  wave
               action, turbidity,  or  high concentration of
               salts  may prevent the growth of  hydrophytes;
                (3)  areas  with  hydrophytes  but  nonhydric
               soils,  such  as   margins  of impoundments  or
               excavations  where  hydrophytes   have  become
               established  but  hydric soils  have  not  yet
               developed;  (4)  areas without  soils but with
               hydrophytes   such  as   the  seaweed-covered
               portion of  rocky  shores;  and  (5)  wetlands
               without soil and  without hydrophytes, such as
               gravel beaches   or  rocky  shores  without
               vegetation.
                            15

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                    TABLE  1.  (continued)
Limits:
               The  upland  limit of wetland is designated as
                (1)    the    boundary   between   land   with
               predominantly hydrophytic cover and land with
               predominantly mesophytic or xerophytic cover;
                (2)   the  boundary  between   soil   that  is
               predominantly   hydric   and   soil   that  is
               predominantly  nonhydric;  or  (3)  in  the case
               of  wetlands without vegetation  or  soil, the
               boundary  between  land  that   is  flooded  or
               saturated  at some  time each year  and  land
               that  is not.   The  boundary  between wetland
               and   deepwater   habitat  in   the  Marine  and
               Estuarine    systems   coincides   with   the
               elevation of the extreme low  water of spring
               tide;    permanently   flooded    areas   are
               considered   deepwater   habitats  in   these
               systems.    The  boundary between  wetland and
               deepwater    habitat    in     the    Riverine,
               Lacustrine,  and Palustrine  systems  lies at a
               depth of 2 m   (6.6 feet)  below low  water;
               however, if emergents,  shrubs,  or trees grow
               beyond  this   depth  at  any   time,   their
               deepwater edge  is the boundary.
                            16

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 TABLE 2. DEFINITION OF DEEPWATER HABITATS USED BY THE U.S.
    FISH  AND  WILDLIFE SERVICE FROM COWARDIN ET AL.  (1979)
Definition:
Explanation:
Limits:
               Deepwater  Habitats  are permanently  flooded
               lands  lying below the  deepwater  boundary of
               wetlands.      Deepwater   habitats   include
               environments where surface water is permanent
               and  often deep,  so  that water,  rather than
               air, is the principal medium within which the
               dominant  organisms live, whether  or not they
               are  attached   to the   substrate.     As  in
               wetlands,    the    dominant    plants    are
               hydrophytes;   however,   the  substrates  are
               considered  nonsoil  because the water  is too
               deep to support emergent vegetation.
               Wetlands  and Deepwater Habitats  are defined
               separately  because  traditionally  the  term
               wetland   has   not  included  deep  permanent
               water; however, both must be considered in an
               ecological approach to classification.
               The  boundary  between  wetland  and deepwater
               habitat  in  the Marine  and Estuarine systems
               coincides with the elevation  of  the extreme
               low water of spring tide; permanently flooded
               areas  are  considered  deepwater  habitats  in
               these  systems.   The boundary between wetland
               and   deepwater  habitat   in   the  Riverine,
               Lacustrine,  and  Palustrine systems lies at a
               depth  of 2 m  (6.6 feet)  below  low  water;
               however,  if emergents,  shrubs,  or trees grow
               beyond   this   depth   at  any  time,   their
               deepwater edge is the boundary.
                            17

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  TABLE 3. DEFINITIONS OF THE FIVE MAJOR SYSTEMS*  (MARINE,
 ESTUARINE, RIVERINE, LACUSTRINE, AND PALUSTRINE**) USED BY
 THE U.S. FISH AND WILDLIFE  SERVICE  IN CLASSIFYING WETLANDS
     AND DEEPWATER HABITATS  FROM COWARDIN ET AL.  (1979)
Marine:
   Definition:
   Limits:
               The Marine  System consists of the open ocean
               overlying   the  continental  shelf  and  its
               associated  high-energy  coastline.    Marine
               habitats   are  exposed  to   the  waves  and
               currents  of  the  open  ocean  and  the water
               regimes  are determined primarily  by the ebb
               and flow of oceanic tides.  Salinities exceed
               30 °/00  with   little  or  no  dilution  except
               outside  the  mouths   of  estuaries.    Shallow
               coastal    indentations    or   bays    without
               appreciable  freshwater  inflow,   and  coasts
               with  exposed  rocky islands  that provide the
               mainland with little  or  no shelter  from wind
               and  waves,  are  also  considered part  of the
               Marine  System  because  they  support  typical
               marine biota.
               The Marine  System extends  from the  outer edge
               of the  continental  shelf shoreward to one of
               three lines:  (1)  the landward limit of tidal
               inundation   (extreme  high water   of  spring
               tides),   including   the   splash   zone  from
               breaking  waves;  (2)  the  seaward  limit  of
               wetland emergents,  trees,  or  shrubs;  or  (3)
               the  seaward  limit  of the Estuarine  System,
               where  this  limit   is  determined  by  factors
               other than  vegetation.
     The  term system  refers to  a complex  of wetlands and
     deepwater habitats that  shares the influence of similar
     hydrologic,  geomorphologic,  chemical,   or  biological
     factors.
**
     The   first   four  systems,   i.e.,  Marine,  Estuarine,
     Riverine,  and  Lacustrine,   include  both  wetland  and
     deepwater   habitats  whereas   the   Palustrine  System
     includes only wetland habitats.
                            18

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                    TABLE 3.  (continued)
Estuarine:

   Definition:
               The  Estuarine  System consists  of deepwater
               tidal  habitats  and adjacent  tidal  wetlands
               that  are  usually  semienclosed  by  land but
               have  open,  partly  obstructed,  or  sporadic
               access to  the open ocean,  and in which ocean
               water  is  at  least  occasionally  diluted by
               freshwater   runoff  from  the   land.     The
               salinity may be periodically increased above
               that of the  open  ocean by evaporation.  Along
               some    low-energy   coastlines    there   is
               appreciable  dilution  of  sea water.  Offshore
               areas  with   typical  estuarine  plants  and
               animals,  such  as red mangroves  (Rhizophora
               mangle)  and  eastern  oysters  (Crassostrea
               virginica) ,   are   also    included  in   the
               Estuarine  System.

   Limits:
               The Estuarine  System extends  (I) upstream and
               landward to  where ocean-derived  salts measure
               less  than   0.5  °/00  during  the  period  of
               average annual low flow;  (2)  to an imaginary
               line  closing the  mouth  of a  river,  bay, or
               sound;  and   (3)   to  the  seaward  limit  of
               wetland  emergents,  shrubs,   or trees  where
               they are not included in (2).  The Estuarine
               System  also  includes   off-shore   areas  of
               continuously diluted sea water.
                            19

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                     TABLE 3.  (continued)
Riverine:

   Definition:
   Limits:
                The Riverine System  includes  all  wetlands  and
                deepwater   habitats    contained    within    a
                channel,  with  two exceptions:   (I)  wetlands
                dominated   by   trees,   shrubs,    persistent
                emergents,  emergent  mosses,  or  lichens,  and
                (2)  habitats  with  water  containing  ocean-
                derived  salts  in  excess  of  0.5 °/0o-     A
                channel  is  "an open  conduit  either naturally
                or artificially created which periodically or
                continuously contains  moving water,  or which
                forms  a  connecting link between two bodies of
                standing water"  (Langbein and Iseri,  1960).
               The   Riverine  System   is   bounded  on  the
               landward  side by  upland, by the channel bank
                (including  natural and  man-made  levees),   or
               by   wetland  dominated   by  trees,  shrubs,
               persistent  emergents,   emergent  mosses,   or
               lichens.   In braided  streams,  the system  is
               bounded by the banks forming the outer  limits
               of  the depression within  which the braiding
               occurs.   The Riverine  System  terminates   at
               the  downstream end where the concentration  of
               ocean-derived salts  in the water exceeds 0.5
               °/00 during the period of annual average low
               flow,  or  where the channel  enters a lake.   It
               terminates    at   the   upstream   end   where
               tributary streams  originate,   or   where  the
               channel  leaves a  lake.   -Springs discharging
               into a channel  are considered part  of  the
               Riverine  System.
                            20

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                    TABLE 3.  (continued)
Lacustrine:

   Definition:
               The  Lacustrine System  includes  wetlands and
               deepwater habitats  with all of the following
               characteristics:    (1)    situated    in   a
               topographic  depression  or  a  dammed   river
               channel;    (2)   lacking    trees,    shrubs,
               persistent  emergents,   emergent   mosses  or
               lichens with greater than 30% areal coverage/-
               and  (3)  total area exceeds  8  ha  (20 acres).
               Similar   wetland   and  deepwater   habitats
               totaling less  than  8  ha are also included in
               the  Lacustrine  System  if  an active   wave-
               formed or bedrock shoreline feature makes up
               all  or part of the boundary, or if the  water
               depth  in  the deepest  part  of  the   basin
               exceeds  2  m  (6.6   feet)   at   low  water.
               Lacustrine waters may be  tidal  or nontidal,
               but  ocean-derived  salinity  is  always  less
               than 0.5
                          00.

   Limits:
               The Lacustrine System is bounded by upland or
               by  wetland  dominated  by   trees,   shrubs,
               persistent  emergents,  emergent  mosses,  or
               lichens.     Lacustrine  systems   formed  by
               damming  a  river  channel  are  bounded  by  a
               contour  approximating  the  normal  spillway
               elevation  or  normal  pool  elevation,  except
               where Palustrine wetlands  extend lakeward of
               the boundary.   Where a river  enters  a  lake,
               the  extension  of  the  Lacustrine  shoreline
               forms the Riverine-Lacustrine boundary.
                            21

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                     TABLE  3.  (continued)
Palustrine:

   Definition:
                The  Palustrine System  includes all  nontidal
                wetlands    dominated   by   trees,    shrubs,
                persistent   emergents,   emergent  mosses   or
                lichens,  and all  such wetlands that  occur  in
                tidal  areas  where  salinity  due  to  ocean-
                derived  salts  is below  0.5 °/00.    It  also
                includes  wetlands  lacking  such vegetation,
                but   with   all   of   the   following   four
                characteristics:  (1)  area less than  8  ha  (20
                acres);   (2)  active  wave-formed  or  bedrock
                shoreline  features lacking;  (3)  water  depth
                in the deepest  part  of  basin  less than 2 m  at
                low  water;   and  (4)  salinity  due  to  ocean-
                derived salts  less than 0.5 °/00.

   Limits:
                The  Palustrine System  is  bounded by  uplands
                or by  any of the  other  four systems.
                            22

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   TABLE  4.  NUMBER AND PERCENTAGE OF SANITARY LANDFILLS  IN
          DELAWARE THAT ARE PROXIMATE TO WETLANDS*
                Number and percentage of sanitary landfills
                  Located in     Located in      Located in
                   or within      or within       or within
                   1/4 mile       1/2 mile         1 mile
Wetland system    No.	%	No.	%	No.	%
All systems**
Marine
Estuarine
Riverine
Lacustrine
Palustrine
2
0
1
0
0
1
66.7
0.0
33.3
0.0
0.0
33.3
3
0
1
0
0
3
100.0
0.0
33.3
0.0
0.0
100.0
3
0
1
0
0
3
100.0
0.0
33.3
0.0
0.0
100.0
     There are  3 sanitary  landfills  in the DPRA  data file
     for the  state  of Delaware and all  of these facilities
     have NWI maps available for site interpretation.

     None of the 3 sanitary landfills included in this study
     in the  state  of Delaware are located more  than a mile
     from any type of wetland.
                           23

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  TABLE  5. NUMBER AND  PERCENTAGE  OF  SANITARY LANDFILLS  IN
     DELAWARE THAT ARE PROXIMATE TO DEEPWATER HABITATS*
                Number and percentage of sanitary landfills
Deepwater
 habitat system
                  Located in
                   or within
                   1/4 mile
                  No.
                            Located in
                             or within
                             1/2 mile
                           No.
 Located in
  or within
   1 mile
No.
All systems**
                        33.3
                                 33.3
      66.7
Marine
Estuarine
Riverine
Lacustrine
0
0
1
0
0.0
0.0
33.3
0.0
0
1
1
0
0.0
33.3
33.3
0.0
0
1
2
0
0.0
33.3
66.7
0.0
**
There are  3 sanitary  landfills  in the DPRA  data file
for the  state  of Delaware and all  of  these facilities
have NWI maps available for site interpretation.

One (33.3 percent) of the 3 sanitary landfills included
in this study in the state of Delaware are located more
than a mile from any type of deepwater habitat.
                           24

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   TABLE 6.  NUMBER AND PERCENTAGE OF SANITARY LANDFILLS  IN
 DELAWARE THAT ARE PROXIMATE TO EITHER WETLANDS OR DEEPWATER
                          HABITATS*
                Number and percentage of sanitary landfills
                  Located in
                   or within
                   1/4 mile
                            Located in
                             or within
                             1/2 mile
Located in
or within
  1 mile
System
All systems**
No. %
2 66.7
No.
3
%
100.0
No. %
3 100.0
Marine
Estuarine
Riverine
Lacustrine
Palustrine***
0
1
1
0
1
0.0
33.3
33.3
0.0
33.3
0
1
1
0
3
0.0
33.3
33.3
0.0
100.0
0
1
2
0
3
0.0
33.3
66.7
0.0
100.0
     There  are  3 sanitary  landfills  in the DPRA  data file
     for the  state  of Delaware and all  of these facilities
     have NWI maps available for site interpretation.
**
***
None of the 3 sanitary landfills included in this study
in the  state  of Delaware are  located  more  than a mile
from any type of wetland or deepwater habitat.

The Palustrine system includes only wetlands.
                            25

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