December 1994, Issue No. 10 (PDF) by zud45877

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									                                    United States                              Solid Waste and                     EPA-542-N-94-009
                                    Environmental Protection                   Emergency Response                  December 1994
                                    Agency                                     (5102W)                             Issue No. 10




SPONGE TECHNOLOGY FOR GROUND WATER
TREATMENT OF METALS
By Carolyn Esposito, EPA Risk Reduction Engineering Laboratory
T  he Dynaphore, Inc. Forager™         process streams and acid mine         resins, after which the Sponge      had anticipated that replacement
Sponge is an open-celled               drainage.                             can be reused. Alternatively, the   or regeneration of the columns
cellulose sponge incorporating            Here’s how the Sponge works.       Sponge can be compacted for         would not be necessary, some of
an amine-containing chelating          The Sponge is highly porous,          disposal or can be incinerated.     the columns became saturated
polymer that has selective             thereby promoting high rates of         The Sponge can be used in         with cadmium and lead and had
affinity for dissolved heavy           absorption of ions. The               columns, fishnet-type enclosures    to be regenerated during the
metals in both cationic and            polymer in the Sponge provides        or rotating drums. For the NL       demonstration. The capacity of
anionic states. Through the            ligand sites that surround the        demonstration, Sponge cubes         the Sponge for copper was much
EPA’s SITE (Superfund                  metals to form complexes,             were confined in a fishnet bag in   greater as none of the columns
Innovative Technology                  especially with ions of transition-   a series of four columns.           became saturated with copper.
Evaluation) Program, the ability       group heavy metals. The ability       Ground water was pumped             Although the developer’s
of this technology to remove           of the Sponge to preferentially       through a series of four columns    treatment claims for copper,
heavy-metals from contami-             bid toxic heavy metals is             at a treatment flow-rate of one     cadmium and lead were achieved,
nated ground water was                 particularly beneficial for the       gallon per minute or 0.08 bed       the treatment claims for chro-
evaluated at the NL Industries,        treatment of contaminated             volumes per minute. The             mium were not met, with only
Inc. site in Pedricktown, New          natural waters and has advan-         columns were situated on a          32% removal of chromium as
Jersey. The technology effec-          tages over conventional ion           trailer-mounted unit which          trivalent chrome (initial concen-
tively achieved a 97% removal of       exchange or precipitation             included a water heater to raise    trations of 426 µg/l).
copper and lead from average           technologies where valuable ion       the influent temperature by           For more information and/or to get
influent concentrations of 917         exchange sites or chemicals are       approximately 25 degrees            on the mailing list for the
micrograms per liter (µg/l) and        wasted because they also remove       Fahrenheit to increase reaction     Innovative Technology Evaluation
578 µg/l, respectively. There          cations such as calcium,              rates. Four columns were            Report describing the complete
was 90% removal of cadmium             magnesium, aluminum, sodium           reportedly needed to provide        demonstration, call Carolyn Esposito
from influent concentrations of        and potassium. The Forager™           sufficient path length to meet      at EPA's Risk Reduction Engineering
537 µg/l. The Forager™                 Sponge’s low affinity for these       the demonstration treatment         Laboratory in Edison New Jersey at
Sponge can also be utilized to         cations allows these ions, for the    goals. Although the developer       908-906-6895.
remove and concentrate heavy           most part, to pass through the
metals from a wide variety of          system, enabling greater
other contaminated aqueous             absorption of toxic heavy metals.
media such as surface water,           The extent of the affinity of the     THIS M ONTH ’ S C URRENTS CONTAINS NOTES ON ONGO -
landfill leachate and industrial       polymer for metals is influenced      ING RESEARCH AT EPA’s R OBERT s. K ERR E NVIRON -

effluents. According to the            by solution parameters such as        MENTAL R ESEARCH LABORATORY .
developer, the Sponge can              pH, temperature and total ionic
                                                                             SPONGE          T ECHNOLOGY                        1
scavenge metals in concentration       content. Absorbed ions can be
levels of pans per million and         removed from the Sponge by            PCE D ECHLORINATION                                2
parts per billion from industrial      techniques typically employed         SURFACTANTS                                        3
discharges, municipal sewage,          for regeneration of ion exchange
                                                                             RESEARCH                                           3
NATURAL ORGANIC MATTER SUPPORTS
REDUCTIVE DECHLORINATION OF PCE
By Candida C. West, Robert S. Kerr Environmental Research Laboratory
Recent research has shown         organic matter in the vadose     extraction experiment;          support or “drive” reductive
that organic matter extracted     zone might provide primary       however, the mechanism for      dechlorination. First, the
from a soil horizon was able      organic carbon for reductive     this additional extraction is   complete degradation of large
to support reductive dechlori-    biodegradation of PCE. The       not clear. It has been          or complex compounds
nation of tetrachloroethylene     secondary objective was to       observed that the TCE           usually requires the activity of
(PCE). Ongoing research at        examine if TCE saturated         saturated solution extracts     different types of microorgan-
the site where the soil was       water, i.e., simulating          more colloidal material.        isms. Second, under anaero-
collected (Sleeping Bear,         rainwater percolating through    Different volumes (0, 10, 50,   bic conditions the oxidation
Michigan) had been con-           TCE residual, enhanced           100 milliliters) of the TCE/    of organic compounds is
cerned with determining the       either the extraction or         water and water only soil       linked to the reduction of
rates of natural in situ          bioavailability of the organic   extracts were added to          electron acceptors other than
biodegradation of contami-        matter.                          replicate microcosms contain-   oxygen. Previous research
nants; and, there was specula-      Organic carbon from the        ing subsurface core material.   suggests that, in the subsur-
tion that the presence of high    Sleeping Bear site was           All microcosms were spiked      face, reductive dechlorination
concentrations of indigenous      extracted from a high organic    with 5 ppm PCE.                 may be only a minor factor
dissolved or colloidal organic    carbon spodic horizon in the     Chloroethene concentrations     (less than 0.1%) for the
matter might be contributing      vadose zone by using two         were monitored by purge         reduction generated during
to the biodegradative process.    extractants: (I) distilled       and trap GC analysis of         the anaerobic oxidation
Interaction of contaminants       water alone, and (2) distilled   subsamples at various time      reactions.
with indigenous organic           water saturated with approxi-    points.                            Further research activities
matter in soil, sediment and      mately 1000 parts per million      The microcosms were           are needed to identify the
aquifer solids are important in   (ppm) TCE. The soil to           monitored over time to          specific components of the
controlling their fate and        solution ratio was 1:2.6 grams   determine the utilization       soil organic matter being
transport. Organic matter         per gram (g/g); and, the         (dechlorination) of PCE.        mobilized by water and
plays a major role in sorption    solution pH for the distilled    Results of the microcosm        solvent/water mixtures,
and potentially serves-as a       water/soil and the distilled     experiments showed the loss     including simple aromatic
biologically available source     water with TCE/soil was 7.6      of PCE and the production       compounds and organic
of carbon supporting bio-         and 7.47, respectively. After    of daughter products over       acids. Attempts will be made
degradative processes.            overnight extraction, remain-    time for both extracts when     to enrich dechlorination
Organic carbon concentra-         ing TCE was removed from         present in sufficient concen-   activity by enhancements
tions in the vadose zone are      the TCE/water soil extracts      trations indicating that the    such as ferulic acid, vanillic
generally assumed to decrease     by purging with N, gas prior     extracts provide a metaboliz-   acid and guaiacylglycerol.
exponentially from the soil       to dissolved organic carbon      able electron donor capable      For more information, call
surface becoming negligibly       (DOC) analysis and micro-        of supporting microbial         Candida West of EPA's
low to non-existent in the        cosm construction. The           consortia responsible for       Robert S. Kerr Environmental
saturated zone. However,          concentrations of dissolved      reductive dechlorination of     Research Laboratory at 405-
carbon distribution at the        organic carbon in the water      PCE. However, we do not         436-8551. Also, for a fuller
Sleeping Bear site is highly      extract and the TCE-             yet know either the specific    discussion of this research,
complex, having buried            saturated water extract were     identity of these compounds     see: Lyon, William G.,
horizons of high organic          16 and 20 milligrams per liter   or the mechanism of extrac-     Candida C. West, Michelle
matter and organic films on       (mg/l), respectively. The        tion.                           L. Osborn and Guy Sewell,
aquifer solids.                   higher efficiency of carbon        Potentially any organic       “Microbial Utilization of
  The primary objective of        extraction using TCE             substance capable of being      Vadose Zone Organic
the study highlighted here        saturated distilled water was    catabolized under anaerobic     Carbon for Reductive
was to determine if leachable     reproduced in a second           conditions should be able to
                                                                                                          (continued on page 4)
SURFACTANT CONSORTIUM AND PUBLICATIONS
The Robert S. Kerr Environ-         University of Oklahoma on           tions of surfactants, to            Cationic Surfactants
mental Research Laboratory has      November 30, 1994. The              provide peer review of work            The RSKERL has pub-
organized a Consortium for          Consortium was organized by         plans and manuscripts on            lished an Environmental
Surfactant-Based In Situ Aquifer    Robert S. Kerr Environmen-          in situ surfactant use, to          Research Brief on “The Use
Remediation Technologies            tal Research Laboratory             provide education on the use        of Cationic Surfactants to
(Consortium) and will publish       (RSKERL) personnel for the          and implications of surfac-         Modify Aquifer Materials to
proceedings of the meetings.        purpose of providing a central      tants in the subsurface and to      Reduce the Mobility of
The Consortium is described         organization for the evalua-        develop protocols for imple-        Hydrophonic Organic
below, together with informa-       tion and implementation of          mentation of surfactant-            Compounds,” by John C.
tion on ordering not only           surfactant-based innovative         based subsurface remediation.       Westall, Julia Wagner and
Consortium Proceedings but          technologies for in situ            The Consortium is planning          Hua Chen of Oregon State
also information on a recent        aquifer remediation. A total        to hold regular annual              University and Bruce J.
evaluation of cationic surfac-      of 45 participants were             meetings and to publish the         Brownawell of the Waste
tants.                              present for the Consortium          Proceedings of the meetings.        Management Institute,
                                    which included a breakout              To get on the mailing list       Marine Sciences Research
Consortium for Surfactants          into five discussion groups          for a copy of the November         Center at SUNY.
  A meeting of representatives      related to surfactant use:          1994 “Proceedings of the              A copy of the Environmental
from 11 universities, the           surfactant chemistry/compat-         Consortium for Surfactant-         Research Brief (Document No.
Department of Energy, the           ibility, hydrogeology,              Based In Situ Aquifer               EPA/600/S-94/002) can be
Department of Defense and           microbiology, regulatory            Remediation Technologies,”          ordered from CERI at
the U.S. Geological Survey          issues and implementation.          send a fax to Dr. Candida           513-569-7562.
and several private industries,     The consensus of the group           West at RSKERL at 405-436-
including surfactant technol-       was that this organization          8703 who will send you your
ogy users and surfactant            would be useful for sharing         copy of the Proceedings after
manufacturers was held in           information on developments         they are printed.
Norman, Oklahoma at the             in research on demonstra-




RESEARCH IN PROGRESS
The EPA’s Robert S. Kerr            enhanced remediation of             systems for solubilizing and        U. S. Coast Guard Station in
Environmental Research              subsurface material contami-        mobilizing residual and             Traverse City, Michigan.
Laboratory (RSKERL) has             nated with dense non-aqueous        free-phase DNAPLs. Studies
some important research in          phase liquid? (DNAPLs). The         are being carried out to test       Site Characterization.
progress relating to ground         primary emphasis of the             chosen systems for ionic matrix       An essential part of any aquifer
water remediation. What             research is to show the             sensitivities, biodegradability,    remediation project is a site
follows is a brief description of   efficiency of recovery of the       solid phase interactions            characterization that provides
some of these efforts.              surfactant solution. The first      and transport properties.           information necessary to select,
                                    effort, conducted by Dr. David      Dr. Robert Knox will utilize the    design, operate and evaluate an
Surfactants.                        Sabatini, is designed to develop    findings of the first phase of      appropriate remedial technol-
  Working under two coopera-        an environmentally acceptable       the investigation to design and     ogy. Carl Enfield at RSKERL is
tive agreements with the            system for enhancing pump           conduct a small-scale field study   working with Captain Jeffrey
University of Oklahoma,             and-treat systems. The              of surf&ant-enhanced                Stinson under an Interagency
Dr. Candida West of RSKERL          approach involves measuring         contaminant removal and             Agreement to thoroughly
is involved with research           the efficiency and effectiveness    surfactant recovery using a         characterize a site at Tyndall Air
directed at the surfactant          of specific classes of surfactant   recirculating well system at the    Force Base using ground
                                                                                                                       (continued on page 4)
Research continued from page 3               Evaluation of Cosolvent               and 51 µg/l vinyl chloride were     chromate and TCE at the site.
penetrating radar and other                  Enhanced In-Situ                      used. Effluent chromate             Potential long-term plans are to
seismic techniques, cone                     Remediation,” is being carried        concentrations were below           install a permeable reactive wall
penetrometer investigations and              out as a pilot-scale field study at   detection (0.005 mg/l) using        at the site composed of
fiber optic spectroscopy. The                Hill Air Force Base in Utah           flow rates ranging from 0.5         elemental iron to passively
goal of the project is to deter-             using sheet piling cells to provide   to 4.0 liters per minute.           remediate both the chromate
mine the feasibility of using                hydraulic containment.                Reductions in the concentra-        and TCE ground water
selected technologies to enhance                                                   tions of organic compounds          contamination.
the performance of a pump                    Chromate and TCE                      ranged from 14 to 99 percent           GROUND WATER
and-treat system. A second site,             Treatment                             depending upon the flow rate.       CURRENTS is monitoring the
selected from nine Department                   A RSKERL research team has         An array of these large “col-        progress of these research efforts
of Defense test facilities, will also        evaluated the use of elemental        umns” is proposed as a means        We will provide additional
be included in this investigation.           iron as a surface treatment           of intercepting the leading edges    findings of this research as they
                                             alternative for chromate and          of overlapping plumes of            become available.
Cosolvent-Enhanced                           trichloroethylene (TCE)
Remediation.                                 extracted from contaminated           PCE continued from page 2           SECOND INTERNATIONAL
  Lynn Wood of RSKERL is                     ground water at the U.S. Coast        Dechlorination of PCE,”             SYMPOSIUM ON IN SITU
conducting a research project                Guard Support Center at               submitted to JOURNAL OF             BIORECLAMATION,
under a Cooperative Agreement                Elizabeth City, North Carolina.       ENVIRONMENTAL                       April 5-8, 1993, San Diego,
with the University of Florida to            The field test involved the use of    SCIENCE & HEALTH;                   CA; West, C. C., W. G. Lyon,
evaluate the feasibility of using            two 55-gallon drums packed            Wilson, J. T., D. H. Kampbell       D. L. Ross and L. K.
miscible organic cosolvents such             with two different types of           and J. Armstrong, “Natural          Pennington, "Investigation of
as alcohols to remediate                     elemental iron mixed with             Bioreclamation of                   the Vertical Distribution and
subsurface environment                       aquifer material from the site.       Alkylbenzenes (BTEX) From           Morphology of Indigenous
contaminated by nonaqueous                   Influent concentrations of            a Gasoline Spill in Ground-         Organic Matter at the Sleeping
phase liquid (NAPL)                          8 milligrams per liter (mg/l)         water,” in R. E. Hinchee and        Bear Site, Michigan, “ENVI-
hydrophobicorganic chemicals.                chromate, 717 micrograms per          B. C. Alleman, eds.,                RONMENTAL GEOLOGY
The project, entitled “Field-                liter (µg/l) TCE, 194 µg/l c-DCE      PROCEEDINGS OF THE                  (in press).




                                        United States                              Solid Waste and                     EPA-542-N-94-009
                                        Environmental Protection                   Emergency Response                  December 1994
                                        Agency                                     (5102W)                             Issue No. 10

								
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