and
                                                                               .


PURPOSE

This                                             to

           and other site                           the
    of     and site                    to         a
          for                    to          or
                            121(b) of the
                                     and        Act
(CERCLA)         the
tion        (EPA) to               that
        and                              or
                    to the                          and
to                     In which
and                   the volume,        or       of
                              and            as a
                  This              the use of con-
                for                                  at
       and other                              this is a
                    and                         the
       and         of           wetlands         are
diverse.




                                                  In
                      and nutrient
        and
                          and                 The
          is
of alt        and                      The      for
        and                 of                   in
          of the United              In the            of
                          for        treatment. The
                            in
treatment of                             well
and are          in                   (EPA
et al, 1995,         1989,       and               and
       1993).                            the use of
                   to
            as mine         is not as
This                           the use of
                  of
and
In        the             of
ogy In the             has        on the           of
         and      mine           The
       of       and the                          (TVA)
                                   In           the
                            to
The        of               is            in
                      (1994) and the TVA       are
         in                                   (1989)
and        (1993),      mine
          by the Colorado        of       the      of
          the      of                  of        and
         and others. Further,                   (for
              and
          to                         on         of the


The          of                                in the
                    is          by               of iron
and               from the           of
        by                At       pH, FeS,,
             to air              to              iron and
                  a pH of 4,0,
                                      can be
      by                                     can
       suit ur          by        1                   in
the
(1)  2
                    H2O -> 2 Fe2* + 4 SO/ + 4 B*
(2)
                           can       the
           Iron          In         1 to     iron by
            2,
                              2H2G
          iron          in this        can
         to                  iron         3) or
     an                  (FeCOHJj) and
     tion 4).
(3)


-------
(4)  2 Fe** + 6 H2O -» 2 Fe(OH)3 + 6 H*

    The overall reaction for the oxidation of pyrite is the sum
    of          1,2 and 4 (reaction 5).

(5)  4 FeS4 + 15 O2 + 14 HZO -» 4 Fe(OH)s + 16 H* + 8 SO4'

At         by equation 5, pyrite weathering           a
     amount of iron and acidity (low pH) to     mine drain-
     Moreover,                     in the            of
coal mine discharge typically treat water containing high
      (50 to 500  milligrams per liter [mg/L]) of iron and low-
to-moderate pH (4 to 7). Figure 1  provides              of
both aerobic and anaerobe constructed wetlandi showing the
primary metal removal mechanisms      in     system. In
aerobic wetlands, the iron is removed primarily by oxidation
followed by precipitation of iron hydroxides (equations 2 and
4) orjarosite, an amorphous iron sulfate.

The removal of      by anaerobic constructed         is a
complex combination of chemical precipitation, sorptive and
biologically          precipitation            In
sufate-reducing         within the wetlands produce hydro-
gen sulfide that      with          metals to form insoluble
and slightly soluble               The metal
          from the         solution and are filtered out by
the solid material (substrate) that        up the wetland.  The
         material's ability to support suHate-reducing bacteria
and filter out the metal        is important to the effective-
     of the anaerobic constructed wetland.

Table 1       the effectiveness of constructed wetland
technology on general contaminant groups for waters.
          of            within the contaminant       are
provided in the                            For Treatment of
CERCLA Soils and Sludges (EPA 1988b). However, perfor-
mance              in this bulletin may not be directly
          to all mining  or Superfund      Numerous
variables including the type of contamination, concentration of
contaminants, alkalinity within the mine drainage,  site climate,
and topography will      the            of the constructed
wetland          A thorough characterization of the contami-
nant             through chemical analysis and
geoehemical modeling is highly recommended. In addition, a
well         and conducted testability study is also recom-
mended.



Constructed wetlands vary in size and complexity depending
on the wastewater stream to be        the capacity required,
and the required  level of remediation. There are generally
           of constructed wetlands:
        (FWS), subsurface flow         (SF), and
plant         (APS) (EPA 1988a). An FWS        (Figure 1
top) typically         of shallow       or         with slow
flowing water and      life.  An SF wetland (Figure 1 bottom)
typically         of       or channels filled with a
                 which the      flows through rather than
over as in an FWS. An  APS is           an FWS with
somewhat        channels  containing floating or suspended
plants such as water hyacinths or microorganisms such as
       The different      of         can be      alone, in
combination, or with other           technologies to
        a variety of treatment

In general, FWS and APS are                that remove
       primarily by       oxidation of iron followed by
precipitation of iron hydroxidei, which      to the removal of
other metals.  In addition, anaerobic removal of some
may occur in the              of the FWS and APS wet-
lands.  FWS and APS         are most          in
removing iron, manganese,        and selenium from mine
        with moderately low to neutral pH        et al.
1 994).  Iron is removed as a hydroxide or        as previ-
ously          Arsenic and selenium are         to sorb to
the iron hydroxide as it            and        out. Manga-
     is      removed as an          the iron has precipi-
     and the hydrogen ion concentration lowered to nearty
neutral conditions  (Hedin et al. 1 994). Liming or the
of alkalinity to the      through an anoxic limestone drain
prior to the FWS         the formation of  iron  hydroxides and
           oxides. Aquatic       and microorganisms  may
also consume acidity (equation 6) of APS        through
photosynthetic activity with similar results.

(6)   106 CO2 + 16 NO"3 + HPO4- + 122 H2O +  18 H* —light -»
Lowering the hydrogen ion concentration to a pH of 9.5 or
greater                     the                     rate,
thus enhancing manganese removal from most mine drain-
     (Bureau of       1 885),

Figure 2 provides a        schematic of a       wetland
       that may include plants. The various       of
        In Figure 2 can be      in a variety of combinations
to achieve the          treatment. This FWS design
         by TVA         of       with a natural or con-
        subsurface barrier of clay or impervious geotechnical
        (Brodie 1993). The        shown in Figure 2
an anoxic limestone drain with      and shallow ponds,
         a rock filter, and an        bed (usually limestone)
to              mine drainage. As previously mentioned,
the limestone drain          the alkalinity of the mine
drainage, thereby enhancing iron hydroxide precipitation in
the      pond and      marsh. The          alkalinity and
     of iron allow manganese       to form with removal by
precipitation. Additional            fe removed in  the rock
filter by adsorption to the rock and           by
growing on the rock surfaces.  Finally,  pH is        to
regulatory      by chemical amendment in the         bed
followed by                     (TSS) removal in the
polishing cell. The various     shown in Figure 2 can be
     in any combination to     site-specific treatment
requirements.

SF wetlands are anaerobic        that vary significantly in
size and complexity. Figure 3         a           wetland
        constructed in an                (Frostman 1993).
A      of SF wetland     was        by simply construct-
ing a      of berms and using     as a         material.
Limestone      (Figure 3) can be      in confunetion with SF
constructed         to         the alkalinity, and induce


-------
      FIGURE 1:  AQUATIC CHEMISTRY OF WETLAND SYSTEMS
                       AEROBIC
                ANAEROBIC UPFLOW
   Fto* Direettoii




SRB     IMsefes Bacteria
    So'*!
                                    Bulletin: Constructed Wetlands Treatment

-------

   Notes:
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-------
                        3:
                                                                        ' LIMESTONE BED
                                                                                ' LATERAL FLOW DISTRIBUTION
                                                                                   PEAT MIXTURE
                                                                                                 PEAT MIXTURE
                                               OPEN WATER POOL
  %     DIRECTION OF WATER FLOW
         LIMESTONE BED
r-"-"-"-1  PEAT MIXTURE TREATMENT
	COMTAy 1NATED DRAINAGE
	— EXTENT OF WETLAND
        FLOW DISPERSION
mot*:   eewrauoED WEOMfm fan WMER OUAUTY MFROVEMENT, a. MOSHRI, EDITOR, ins
                               WATER POOL
                                                                     WATER POOL
      4:                                                       OF AN              SF
70Z.QEOFMMC
GEOQBID	
70LGEOFABRIC
                              PERFORATED EFFLUENT PIPING
                              TIE TO GEOGRID	'
                                 PERFORATED —
                                 INFLUENT HnNQ
                                7 ai. QEOFABRIC
                                QEOHET	
                                QEOSYHTHETIC
                                OAYLIKER
                                18m.GEOFABRIO
                FRCM: CAMP       « McKEE, 1993
                                                         SUBSTRATi



-------
                              TABLE 2
iliipHiSt;
Ag
Al
Cd
Co
Cr
Cu
Fe
Hg
Mg
Mn
Mo
NI
Pb
Zo

Ag,S
AIA
CdS
CoS
NF
Cu,S
FeS
HgS
MgS
MnS
Moft
NiS
PbS
ZnS

-9.36
•117.7
-33.6
-19.8
NA
-20.6
-23.3
-11.7
NB
-49.9
-53.8
-17.7
-22.2
-47.7

lxlO-»
ND
1x10-"
7xlO-»
NA
SxlO"4'
8x10-"
2x10'"
ND
3x10-"
ND
3x10-"
3x10-"
2110*
 Notes:
      NF
      NA
      ND
Formation constant (from the dementi) from Garrels and Christ 199(1
Not formed
Not applicable
No data
In general, SF         are anaerobic        that remove
metal contaminants by reaction with hydrogen sulfide pro-
duced by suifate-reducing        forming insoluble metal
sulfides.  Table 2 provides metal sulfide formation (from the
elements) and solubility product     for common mine
drainage      contaminants.  The more        the
formation constant, the stronger the         for the metal
sulfide to form. The      indicate that all of
      form a      sulfide, with the         of chromium.
Aluminum, cadmium, iron,            molybdenum, and zinc
     the         tendencies to form        however, the
aluminum                   in         environments.
Solubility product             the strong tendency of the
metal and the sulfide ion to          from aqueous solution.
However, solubility product determinations do not consider
metal complexaton and their use may result in misleading
precipitation or solubility predictions.  For example, the
solubility products of HgS and PbS      by 25       of
magnitude, but their aqueous solubilities may be quite similar
(Stumm and Morgan 1981}.  For these         the use of an
aqueous geochemical model, such as MINTEQA2, to evaluate
metal speciation and complexation is  encouraged. In addi-
tion,        metal removal with SF         can be mod-
    with MINTEQAK, a program         for        and
anaerobic wetland modeling (Klusman 1993).
            The flow        of SF         is simple. The
            treatment       may first flow through a bed of
            crushed limestone to         alkalinity and
            induce       metals oxidation and precipitation.
            The         then flows into the wetland cell
            where it flows through the substrate.  Depending
            on the cell design, the         can flow either
            vertically up or down or horizontally through the
                     Within the substrate, inorganic
            contaminants are        precipitated, or
            biologically reduced and            The
                   water then flows out of the cell where it
            may flow into another cell or polishing pond.
            Generally,               of 50 to 100 hours
            have          successfully in SF wetlands.
            Maintaining proper flow of the mine drainage
            through the         may require frequent
            adjustment.



            This       provides                   for
                   constructed wetlands previously
            evaluated or currently being evaluated.   One of
            the first                    to      acid mine
            drainage     the SIMCO        (Coshocton
            County, Ohio)          in 1985. The
                           of four               by small
                 followed by     larger settling ponds.
            The total     of the        is 4,138
                   (m*) and is planted with       (Typha
                    The            are          of 15
            centimeters (cm) of crushed limestone overlain
            with 45  cm of      mushroom compost.
Evaluation of the  SIMCO        conducted by
from Pennsylvania      University indicated removal effi-
ciency has                 over the 8      of operation
(Stark el al. 1994). Iron removal           in     were
approximately 20 to 50 percent, and          1991 and 1993
       from 70 to 100 percent.                     removal
         not                however, a comparison of
mean influent and effluent manganese concentrations
                   is not removed by the SIMCO con-
       wetland.

        1984 and 1993, the Bureau of       monitored 13
constructed                  to      coal mine drainage.
The       of the monitoring are           in detail by Hedin
et al. (1994). These         include          wetlands in
combination with  anoxic limestone drains, retention ponds,
and modified ditches. In addition, a variety of
            evaluated and            the most common
              during the         The        determined
dilution is an important        within              and
must be determined to accurately evaluate metal removal
      The results     indicate alkalinity in the mine drainage
improves the wetlands removal of iron. For          iron
removal         53       in the effluent from the third cell
of the Latrobe wetland (0 alkalinity in drainage) while iron
removal in effluent                 from the Donegal
wetland         85 percent. The influent to the

                                                                                                                 6

-------
wetland contained 202      of         and both
                   of limestone and
compost. Finally, the              oxygen transfer Is the
              in Iron removal          and            in
     constructed

TVA constructed 14                for               at
coal               Impoundment 1 (IMP1) is one of 12 TVA
          wetlands and               at the  Fabius coal
                       IMP1 contains four aerobic cells
and covers 5,700 ma. The             has a pH of 3.1, iron
            of 69       and manganese             of
9.3 mg/L Effluent water from IMP1           wetlands
        0.9      of     1.8 mg/L of manganese, and a pH
of 6.7.  Originally, five       were       at IMP1 including
broadleaf                     wool
          rush (Juncus
hyemala), and
                Today, more than 70            been
        in 1MP1  with the         cattail, wool grass,
          and rice cutgrass                  the dominant
plant life. In addition, the       stream draining the
              than five invertebrate                 the
stream contains more     30                   (Brodie
     and       minnow

The EPA           Innovative
        is evaluating               upflow and downfiow
SF        at the        Tunnel, Silver Plume,
The demonstration             the         operation and
       of an              at the Big 5 Tunnel
        Colorado) within the SITE         Technology
Program            The mine drainage from the
       contains elevated      of    (45 to 90  mg/L) at a
neutral pH.       3         data for both             the
first 12 months of operation. The     for the first year
indicate the       eel           removes better than 99
       of the zinc contamination in        and fall, and the
removal                 to 70        in the winter. The
         cell         70 to 85              the first year.
In addition,       of 48-hour     toxicity
                                    and
dub/a Indicate both      are          the toxicity of the mine
         The demonstration of the SF
at the Burieigh Tunnel                 August 1995.
Technology Status

         there are several hundred           and natural
wetlands treating coal             in the        United
       The             of              is          in
several publications                 (1989), Moshiri
the            of annual         of the
Mining and Reclamation           and United
Bureau of             (United       Bureau of
       Publication         and       et al. 1994).

In addition, many constructed                 to treat
metal mine              been built and      or are
      by EPA, various              and         In
Colorado, the            of Minerals and        has
       constructed wetland        to
In             the            of Environmental
          a     professional                for
from coal mine          and determined constructed
             the  best available           for the treatment
of alkaline or                  (Hellier et al. 1994).
          wetlands treatment is                for the
full-scale remedy of the        Tunnel drainage.

A state-of-the-art,                 has been constructed at
the                in the Cornwall     of
England. The             the      Jane abandoned tin
                     levels of cadmium,             and
iron. The design of the                      wetland Is
similar to the             shown in Figure 2. The
      with an anoxic             by an anoxic drain, then
an        cell,        by an anaerobic cell, and      a
     filter.  Both  the anoxic              and the anaerobic
cell use              to prevent
             cells.  The                   has begun a
2-year                     period.

EPA has                 a wetland database that
               permit, cell
and                    for 178 municipal wetland
(EPA
                                BURLEIGH          CONSTRUCTED WETL&HBS
                                       SITE DEMONSTRATION
                         AVERAGE ZINC CONCENTRATIONS        IN 1994 AND

Influent
Upiow
Downflo*
faW*&a&a^«**i^^
56.7
0.16
9.7
62.0
0.28
15.4
fegissk\MfeMS,*,SjJi«s
50.4
0.23
11.5
J-^JSB^^^I^™^™^
49.6
0.24
10.1
58.0
0.24
1B.9

66.1
0.48
14.9

57.0
1.1
16.4
56.6
2.8
14.8

62.9
6.8
12.1

63.0
9.0
8.8
56.3
12.1
9.0
58.0
17.4
11.1
                                                  Engineering Bulletin: Constructed Wetlands Treatment

-------
Limitations

Constructed wetland         typically have         land
requirements compared to conventional treatment
Thus, in      with high land values, a constructed wetland
treatment        may not be            Land
relatively close to the       of contaminated water is
          to avoid         transport of contaminated water.
Land that is relatively level         the construction of
wetlands, white         with             and          will
make construction more difficult, costly, and potentially
unsafe.

The climate of potential           wetland     can limit the
effectiveness and operation of the system.  Extended
of       cold, extreme hot and arid conditions, and frequent
       storms or flooding may      in operational and
performance problems.          cold can       a wetland
and substantially       the microbial  population, rendering ft
ineffective for an extended period     thawing. The
water surface      and plant life           with wetlands
enhance evaporation and evapotranspiration.  A constructed
wetland may            dry up at a site with  low      flow
     in a hot and arid location. If the wetland is not
for cyclical periods of wet and dry, it may be less
during the wet periods.  Constructing wetlands in      with
frequent flooding or       storms can lead to washout of
                 or         of the microorganisms to toxic
      of metal contamination. Extensive engineering controls
to overcome climatic or geographic limitations may eliminate
the cost and maintenance            that
wetlands attractive.

Contaminant      and concentrations in the  treatment
can be limiting       for constructed wetland
             High concentrations of contaminants may
shorten the effective life of a constructed wetland, which have
a limited life      on the volume of the wetland or the
amount of organic                in  the wetland.
limitations include the number of      for adsorption of
inorganic contaminants and the amount of organic nutrients
for biological activity. The wetland is no longer
the     are full and the organic matter is exhausted. At this
point, the wetland must be        to remove the
          High concentrations of                 in the
treatment stream may           the life of a constructed
wetland. Suspended      fill               and the
         pore         reducing permeability and preventing
flow through the treatment       in

Cost

In general, there are no typical unit      of constructed
         due to site-specific conditions and treatment
requirements. The       of            and construction
required will dramatically      the cost. The
     with FWS         typically     to     coal mine
          are          per     while     for SF wetlands
are       on volume.       and                  for
constructing various          are reported in the literature
(EPA       Hammer      Moshiri       EPA
An         of the        wetland      was reported as
$3.58/m2 to $32.06fnf of wetland in a study of constructed
wetlands for acid mine drainage treatment by TVA
(Brodie 1988). A cost study of       wetlands for treating
         at coal mines conducted by the United
Bureau of                an        cost of approximately
$10.00/m2 of wetland (Kleinmann 1995).  Construction
of the          SF        at the Burieigh Tunnel, Silver
Plume, Colorado              to be $570 per cubic meter.
     that this  cost is       on wetland volume. This SF is a
highly engineered       with multilayer liners; sophisticated
piping, distribution, and collection         and a customized
                         to       year-round at high
       (9,150 feet            sea level).

Constructing         involves common construction tech-
niques and         which      development of a construc-
tion             straightforward. Operation and mainte-
nance      are comparatively      compared to traditional
treatment systems. One cost that is often overlooked is the
cost of         and         of the               (SF) or
        and         of bottom          (FWS). The
             can be significant if the          or sediment
is allowed to        a                 due to high metal
concentrations. The cost of               or
        may be     by       recovery from the material. If
low-cost, level land is          constructed         could
be an economical treatment method when compared  with
other treatment options.

In conclusion, constructed          treatment         to be
effective In removing       from and toxicity in
               Construction              to build
        are inexpensive and readily          Compared to
other      treatment             constructed         may
be a cost-effective alternative.

Acknowledgments

This bulletin was         for the United       Environmen-
tal Protection Agency, Office of          and Development
(ORD) National Risk Management         Laboratory
(NRMRL), Cincinnati, Ohio by PRC Environmental Manage-
ment, Inc. (PRC), under contract No. 68-CO-0047. Mr.
              as the EPA Technical        Manager. Mr. •
Terrence Lyons        as the EPA Work Assignment Man-
      Mr.        Routine was PRC's Project          This
bulletin was written by Mr. Garry Farmer and Mr.
        of PRC.

The following other Agency and contractor personnel have
contributed their time and comments by             in the
      review          or               the engineering
bulletin:

Mr.               NRMRL
Dr. Robert Hedin, Hedin Environmental
Mr.               Knight-Pjfcold and Co.
Dr. Robert Kleinmann, United      Bureau of
Ms. Terry Ruiter, PRC

                                                                                                                  8

-------
                                                REFERENCES
1.    Brad!©, G.A., D.A. Hammer, and D.A. Tom LJanovich.
     1988. Constructed Wetlands for Acid Drainage Control
     in the Tennessee Valley.  United       Bureau of
     Mines Information Circular 9183, pp.  325-331.

2.    Brodie, G.A. 1993. Staged, Aerobic Constructed
     Wetlands to Treat Acid Drainage: Case History of
     Fabius impoundment 1 and Overview of the TVA
     Program. Published in Constructed Wetlands for Water
     Quality Improvement. G.A. Moshini.  Lewis Publishers.
     1993.

3.    Camp Dresser and McKee. 1993.  Clear Creek
     Remedial Design Passive Treatment at Burleigh Tunnel
     Draft Preliminary Design Technical Memorandum.
     June.

4.    Cooper, P.P., and B.C. Findlater, Eds. 1990.  Con-
     structed Wetlands in Water Pollution Control. Proe. Int.
     Conf. on the Use of Constructed Wetlands in Water
     Pollution Control. Pergamon Press, Oxford U.K.

5.    Eger, P. 1992. The Use of Sulfate Reduction to
     Remove Metals From Acid Mine Drainage.  Paper
     presented at the 1992 American Society for Surface
     Mining and Reclamation Meeting. Duluth, MM, June 14-
     18.

6.    Frostman, J.M. 1993. A Peat/Wetland Treatment
     Approach to Addic Mine Drainage Abatement. Pub-
     lished in Constructed Wetlands for Water Quality
     Improvement. G.A. Moshiri. Lewis Publishers.  1993.

7.           R.M. and C.L. Christ. 1990.  Solutions, Minerals
     and Equilibria. Jones and Bartiett, Boston.

8.    Gusek, J.J., J. T. Gormley, and J.W. Sheetz.  1994.
     Design and construction        of pilot-scale passive
     treatment systems for acid roek drainage at metal
     mines.  Proc. Society of Chemical Industry Symposium.
     Chapman and Hall, London.

9.    Hammer, D.A. 1989. Constructed Wetlands for
     Wastewater Treatment. Lewis Publishers.  Chelsea,
     Michigan.

10.  Hedin, R.S., R.W. Narin, and R.L.P. Kleinmann. 1994.
     Passive Treatment of Coal Mine Drainage. United
            Bureau of Mines Information Circular 9389.

11.  Hellier, W.W., Giovannitti, E.F., and P.T. Slack.  1994.
     Best Professional Judgement Analysis for Constructed
     Wetlands as a     Available Technology for the
     Treatment of Post-Mining Groundwater Seeps. United
            Bureau of Mines       Publication SP 06A-94.
12.   Kfeinmann, R, 1995. Personal communication between
     Marie Kadnuck (PRC) and Robert Kleinmann.

13.   Klusman, R.W. 1993. Computer Code to Model
     Constructed Wetlands for Aid in Engineering Design.
     Report to United       Bureau of Mines, Contract
     J0219003.

14.   Moshiri, G.A. 1993. Constructed Wetlands for Water
     Quality Improvement.  Lewis Publishers. Boca Raton,
     Florida.

15.   Reed, S.C., R.W. Crites, and E.J. Middlebrooks.  1995.
     Natural Systems for Waste Management and Treat-
     ment, 2nd Edition. McGraw-Hill, New York.

16.   Stark, L.R., P.M. Williams, S.E. Stevens, Jr., and D.P.
     Eddy. 1994.  Iron Retention and Vegetative Cover at
     the SIMCO Constructed Wetland: An Appraisal Through
     Year Eight of Operation. United       Bureau of Mines
            Publication SP 06A-94.

17.   Staub, M. and R.R.H. Cohen. 1992. A Passive Mine
     Drainage Treatment System as a Bioreaetor. Treatment
     Efficiency, PH Increase and Sulfate Reduction in Two
     Parallel Reactors. Paper presented at the 1992
     National Meeting of the American Society For Surface
     Mining Reclamation, Dulirth, MN. June 14-16, 1992.

18.   Stumm, W. and J.J. Morgan. 1981. Aquatic Chemistry.
     John Wiley and Sons, Inc. New York,  New York.

19.   United States Bureau of Mines. 1985. Control of Acid
     Mine Drainage.  Information Circular, 1C 9027.

20.   United      Environmental Protection Agency (EPA).
     1988a. Constructed Wetlands and Aquatic Plant
     Systems for Municipal Wastewater. EPA/625/1-88/022.
     1988.

21.   EPA.  1988b. Technology Screening Guide for Treat-
     ment of CERCLA Soil and Sludges. EPA/540-2-88/
     OU4.  1988.  pp. 86-89.

22.   EPA.  1993.  Handbook for Constructed Wetlands
     Receiving Add Mine Drainage. EPA/5401 R-93/523.
     September 1993.

23.   EPA.  1994.  Wetlands Treatment Database. EPA/600/
     6-94/002. June 1994.


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Environmental
                                              (G-72)
Cincinnati, OH

Official
Penalty for Private Use
$300
 &       PAID
EPA
  No. G~35
EPA/540/S-96/501

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