"United .States -'•'•. '',   .;-.:  /
                               : environmental Protection v-
                                Agency.   '    "•''"••  ••   :.
                  • EFW54Q/MR-00/5Q4,
                   December2000'  :"
                               SUPERFUND IMNQMT1VE
                               TECHNOLOGY  B/ALUA TIQN
                                Demonstration  Bulletin
                                       ln-Siu Bioremefliaiion Process
 Project Description: The U.S. Environmental Protection.
 Agency (EPA) conducted an evaluation .of .the Enhanced In-
 Situ  Bioremediation. Process., a biostimu.lation technp'lpgy
. developed; by. the U.S.Department of Energy (DOE)' at "the •
• Westinghogse Savannah RiyenPlant sitejn.Aiketi,SC. DQE,
 has licensed the process to  Earth Tech,-'Inc. (Earth Tech).,
 The eyaluati'bn despribed in, this bulletin was carried. out by
' the EPA'Superfund Innovative Technology Evaluation (SITE)
 Program* Earth Tech is utilizing the process.to deliver a rnix-.'•
,ture of air aiid,gaseous phase nutrients,, and/or methane tp
: cpntarriiriated grouiidwater in fractured bedr.ock';at a site in
 Rpanpke, VA^hese enhancements are delivered to cohtami-.
 •nated grpundwater via an injection well and were: designed
 tp'stimuiate and. accelerate the growth of existing microbial
 pppulations, especially 'rhethanptrophs. This type, of aerobic
 bacterium has. the. ability to  metabolize methane and;p.ro- •
 duce enzymies c'apableof degrading chlorinated solvents.and
 their degradation-products tP npnfhazardous constituents.   .

: The  primary components of'Earth Tech's treatment system
 consist of an injection well, air injection-equipment, ground-.
 water monitoring wells; and soil vapor monitoring points. The
 injection, well is  designed to deliver air; nutrients, and.meth-
 surface. For the system evaluated, the air was supplied by a
 'compressor that was capablepf delivering 15-30 psi and ap-
 prpximately SOscfm to the injection well, the rtic-nitoring wells
 and soil y^por triohitprihg. point?, were installed upgradient,
 down-gradient and cross-gradient relative to the injection well
 location to 'delineate the.zone of ihflue.rtce .and to monitor
 groundwater.within and putside of thezprie of influence.The
 . soil vapor monitoring points'can be;designed to release or
 capture'vapors that may build up in the. overburden. The
 . monitoring wells were constructed in a manner to allow therh,
 to be converted toeither irijeptipn wells or soil vapor extrap-
 tion.points. .": '; ,!'•••.•• \'•'•''..'';",:- ':'"'•'':"',. '•'"'••'".-:.; '.'•....
 The-typical •injection' system Consists of air, ^nutrient, and
 methane injection e'quipmeht; all can be housed ina tempo-
 rary building or shed; A'cornpressor Serves as the air source^
 and includes a condensate tank ("trap") With a drain, an air
 line, ..coa.lescing filters arid pressure regulators, apd; valves.
 The' methane and nitrous oxide provide thS source of carbon
 and nitrogen, respectively. Both are provided in standard gas :
 cylinders and are piped into the main air line using regula-.
 ; tors''and;:flow meters. Triethyl.phosphate .(TEP), thp phosr
 phofous source,.is.iri liquidstate..and isstored-in.a.pressure':
 rated steel tank: Arr from the rna n line is'diverted through the
 tanktoi'vo'ialillzQ-theTEP'for^subsurfacedeliyery.Thea,ir,,ril- ..
 trous oxide, ,and TE.P are  injected cbritin.upusly While the •.
 methane;is injected Jb'n'a pulsed schedule, the^metharie js
 closely mpnitored just prior to injecting intp-supsurface wells:  :
• to ensure th'at the injecition concentration'dpes not.exceed,
 4°/o by volume,: thus avoiding the methane lower' explosive .
 limit (LEL) of 5%.; :•.;,. ":   .  ••';/..;'••'••';•.-;';''.': ".-.  ..'' v "' u -'

 Waste Applicability: The' Enhanced In-Situ Bioremediation
. process-is applicable fortreating volatile organic compounds .' •
 (VObs): in groundwater that ca.n be naturally  biodegfa'ded, •
.-'. including some hard to degrade phlprinated ,VOCs.. the mix- -'.
 ture of air.and 'gaseous phase nutrients that is injected into
 the Subsurface provides-an  aerobic environment for. cbntami-  "
"n'ant degfadatipn. Toxic •.products 'resulting from, anaerobic..'
 degradation of chlorinated solvents (e.g:, yinyl chloride) may.  •
 .be broken down completely,-iri.this aerobiP enyironment. The
 in-situppcessls especially applicabiefor.hydrogeologica'lly
 complex sites where injected nutrient flpw paths-are uripep:
 tairt;(i..e.; in fractured bedrock gaseous phase nutrient injec- .
; tionjis more likely to affect  a-larger area, than; liquid .nutrient
, injection).,the process is also applicable in situations' where
^subsurface, utilities limit or'preclude the use of technolpgie's  :
 requiring excavation.  .;-,  v  ',  ..    ,-, :' :.  •        •

 .bemonstratiQn Results: .A pilot-scale .technology demonr..:.
 stration bf.the Enhanced In-Situ Bioremediation process-was
..-conducted from March 1998 to July 1999 at the ITT Indus-'
' tries Night Vfsio'h (ITFNy) .piyision'plaht in Roanoke, VA. The,  \
 JTTNV facility is an actiyie. rnanufacturing plant that produces
 night visiort devices and. related night visio'n products for both'
- goyerrirnerit and cornrnercial customers: C3rpund.water con-,
 tarhination at the facility has resulted from tankJeaks ofboth',.'•'•
 chlbrinated and 'ripn-chlprinated compounds, which were .
 used-as manufacturing cleaning solvents; Remediation, is
.being cohducted at the.facility as a RCRA,Interim Measure .
 (\Mj:, and .is cprnplicated by'target .VOCs occurring in frac-
 •tured bedroclc below -the sUrface.This logistical complexity
• presented by the area geology was a key factor for selectirig
 thei Enhanced'In-Situ.Bioremediatipnprocess.....-'•'    ". '.-';••

 the,demonstration study area was located:adjacent to .
. ITTMV's commercial operations building (Building 3), and was
 immediately dowrigradient of a cpntamination source.that had - .
 .resulted from a leak of an underground waste splvent tank.
 The study area.is the only location at the facility where the.'
 source release has Ppntaminated the grbuhdwater with both:
 chlorinated and non-ch'lorinated groups of VQ.Cs, Several VOQ
     '  '       ''  : '"•         80%Recycleci/Recyclable
                               Printed with vegetable-based ink on
                              . paper that contains a minimum of.,
                               60% post-consumer fiber oontept.-. :
                               processed chlorine tree... •. '•;  •-'.-

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 United States     ,     ,
 Environmental Protection Agency
 .National Risk Management Research Laboratory;
 Cincinnati; OH 45268.  -"

 Official Business      , '
 Penalty for Private Use
 $300    ,.      •,-  '

• EPA/540/MR-00/504
                            PRESORTED STANDARD
                            POSTAGE & FEES PAID
                                     -EPA
                               PERMIT NO. G-35
 compounds'have been detected in.th.e-groundtoater at this
 location above their respective Federal, Maximum Contami-
 nant Level (MCL)iThese compounds include actual spjverits,
 such as 1ri.chloroethe.ne (TCE). arid 1,t,1-tfichlprpethane ;
 (TGA), as welt as' several of their breakdown products, prior
 to the start of trie demonstration methane was present and
 TCE was absent from some-ofthe wells. These'Observations.
 strongly suggest that anaerobic'degradation'..of'TCE was -
. naturally occurring.        • '   .'_"• •••:•"'•'•"; •  \ •  ;'V.-,

 The Earth Tech system installed at the, study area cbnsisted
 of eleven monitoring poihts.These included;an injection well,
' four monitoring wells.loca.ted within, the radius of influence,.-'
 two monitoring wells located outside of the radius of -influ-.
t ence (i.e., ohe upgradtent and one downgradient), and four.
 soil vapor monitoring points. Selection  of the spe'cific .con-
 taminants and wells to evaluate was based on review of his- •
 torical site data, results from a pre-demonstrati.on sampling
 event, and on a statisticai'analysis. Emphasis.was placed 911- •
 sampling the four monitoring'wells Jocated within the.radius
 of'influence, which were designated as "critical, welfe" F-our
. specific contaminants_were associated- with these wells that
 exhibitedacceptable temporal and spatial variability for eyalu-;
 ating the technology. These  "critical  analytes""included.:
 chloroethane '(CA); 1,1-Dichlor6etharie (1,1-DCA)', cis-1,2-
 Dichloroethene (cis-1,2-DCE), andVinyl Chloride'(VC).TCE •
 was not selected because it did not exhibit acceptable tem-
 poral and spatial variability/.'.     ;  ;   '  .:" .  •    '    '•'•,'•
 The primary objective of the demonstration was to evaluate
 Earth Tech's claim that there'would be a minimurh 6f .75%:.
 reduction (with a 6.1 level of significance) in the grpundwater
, concentration of each of the four critical'ahalytes within the
 zone of influence, following six months; of treatment. How-:
 'ever,- process  optimization and'"modif ications resulted, in -ex-
 tending the evaluation period-to sixteen months. Based on
 the above-mentioned claim artd'pre-dernonstratiph data,- ah
 experimental design was developed to'guide the evaluation,.
 During the baseline and final sampling events, .one •g.round-
, water sample from each of .the four critical wells was coj-
 .lected for VOC analysis-daily for.seven consecutive-days '(fpr
'a total pf.28 samples per event). . ,..""-,'•'  '• -  •,.•':':
 Results from the Earth Tech In^-Situ Biorerriediatibn-.Technol'-
 ogy demonstration are presented in Table 1 and are based
 on the 28 baseline and 28 final sarnples for the four critical
 anajytes. YOG concentrations were.determined by EPA SW-
 846'jyi'etho'd 8260.the results indicate t.hdt the targeted.75%,
^reduction-was achieved or exceeded for two of thefour critj-.
 , cal compounds,,fromi baseline .to final events^   .   • •:  :.  :,'
 •Tsble 1 i Groundwaiter.Results.
Target . V '• .''
Compound
CA . .'-.''•
.1,1-DCA ' ..
cfe-1,2-DCE
,.vo • • -V
; i'. Contaminant .
;' • Concentration . .
... .'• Baseline- Final' v
:'A 330- .'•:
'•' 960
3,100 :.
210'- ;.
-'• 19'b
. 90 -••••'
'. Average.
' „•' Percerit '•.'
'. Reductipn "'
'• SO "V;
:.-./..^l97,^; -
Statistically . •'. ••
.• Significant" . >--i '."•;
•••^'Percent'.' ' ' •
Reduction' -'•.' • - -"-
,' ^'-.'-. ',4 •'•'..":"•' '.'•;, •'.•>"
'•- . • '" ,95 ':-':- •••'.•.'•••'
•-:,; • ..gf:- ;.,;.- .. •• . •;
   Values are the average of 28. results from four wejls, and roundecJ
   totwo'isignlficant.digits.    :-:."..'  ,••.,'.^1.' •  '•';."'' -'..,..,:
   Percent reductions shown represent the Lower Cpnfi'dence-iirrtit
   (LCL)  for the Average Percent Reductfons, wi^h a pit ley^l of
  'significance.,    .':,•'• '':...  "  :.  '   '  .   ,  :  ;,  ',,
 •An, InnovativeTechnoJogy'Evaluatipn Report (ITER) describ-
 ing'- the complete: demonstration will be available in'th'e riear.
 future.-Forfurther information please contact the following: ,


 : EPA Project Manager ;.   •'.''-. •]  ''•;,-:,    •':.;.•'  .
 Vince Gallardo    •   •'.    '..'-•  '   ,  • ,    '     :.;     ,
 ;:u,s.EPA"'';.-..  ;.  : /'.:. :';:• ;•:-':  ,'-\;- !•::' ;- ;•: ,;-.',^ :''.
 .Natioriai.Risk Management.Research Laboratory (NRMRL).
 26 West Martin'Luther King.Jr; Drive   •  '      -:',  ,,
 'Cincinnati, OH 45268 /":;•'  ..'"',:  ;'   '','''•''''-'..':'•".'.
                      .
.;E-rnail:,galIa'rdp'.vincente@ epa.gov

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