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}.CLEARwATE-R r y
<br /> -
<br /> 'c:.R - ,G- R _O U P. 1- C:
<br /> Air Flow Requirernenfs
<br /> z
<br /> r This-calculation is performed to determine the air flowYrequireinent throughout the '
<br /> i selected' contaminated zone lin'.order, t' ,provide sufficient:'oxygen to";maintain
<br /> ? r 1 maxirnu n Y ydrocarbon.. bxodegradat�on. The main' assumption is the "volume -of a
<br /> !soil,through 'which. the.air:'must flow:'. The total volume'"of'void space.'ean be-
<br /> -A"
<br /> e',:} k; calculated based ori art estimate of the volume of'contamiriated'soil: to be�addre' ssed '
<br /> ° by, the,system ,and.an:assumed' value for airfilled 'porosity (generally -takefi to be
<br /> ,�' 30%) IVafixrally,'-the
<br /> 'a' ccuracy';of the results.' reflect _the'.accuracy !of these:es'timated , .
<br /> ; values ::;The productof,the,;void space ,and the utilization-rate yields the:required x
<br /> ' k
<br /> volume of oxygen pe`r .unit time. Assuming :atinosphezic coz%ditions (20'.9% Oz in
<br /> �,; ``air),S the;approximate:air. flow`,regtiired throughout-the selected contaminated -zone
<br /> ` fF. can .be'calculated'in'cubic-feety.minute.
<br /> A;:soil vapor`extract.on.`pilot: test.isusually-conducted'in addition to;the in-situ '
<br /> respiration. test. .Soil.vapor�extraction,pilot_test.i"esult`s will yield permeability„values'
<br /> which:-can then-be-use'd-to-evaluate.the. feasibility of'transporting the oxygen via air c
<br /> 'y.y throug ibut'-the vadase zor►e 'at, the' required flow rates 'y;; The calculation to.
<br /> determine -permeability,`-was;presented•by.Johnson et'=al'(1990). The extraction
<br /> equipment specifications.can`also be determined Jrom data obtained during the,soil
<br /> vapor extraction pilot test., ' ,
<br /> a REFERENCES
<br /> f The following reference`s provide additional information and;;examples of #est.clata
<br /> and evaluations.,;for bioventing systems `and tests xFin various, geological: avid
<br /> ”-envlronmentli settingS.
<br /> Downey, D C..,'Guest' P:R , Cuiley, C A: (1993) Combuied physical and'_biological
<br /> .txeatzment->of diesel contaminated soils.` --In. Contaminated Soils. Diesel Fuel
<br /> ,Contamuiat on, Ed''by P T Kosteck� and E J. CalabresesLdwis'Pub., 218'pp
<br /> S f " • r r fl.R ._ x .ice r,V.�. i"" � � ,
<br /> tR a - _ �-al• _ -t j
<br /> ;Du ont ,R.R. 199
<br /> ' . ' °v.. nin�' Pfuel contarrriafe3) Fundam vtals';of bio
<br /> d . .
<br /> sites: tnviron ':Progre`ss,'Val" P4 6. 1, P:45-53.,
<br /> r '
<br /> ' • { � kyr- '* -L ^ - - _ ry ",y __ � t ' �;; _h _}t } Jr - s ., .
<br /> Hinchde R.E: Ong;:S:K., et.al: (1992). .Test".Plan and Technical Protocol for ;a Field' ,
<br /> Treatabilit A Test;=for. BiOverltlrl U S.'''lAlh Force`Center for.:Environmental
<br /> Y .g
<br /> J y "Excellence;+Brooks'`A,ir Force Base,Texas :80 pp,_
<br /> Johnson, P Cc, 'Kemblowski .'M W., et al {1990) Quantitative analysis for the
<br /> ^cleanu ''of 'h 'drocarbon�contammated soils`:b in-situ-ventin , � Ground: Water'
<br /> P Y Y g
<br /> F Vol. 28,-No = > ,
<br /> r,
<br /> `
<br /> In Situ Respiration Test'Protocols.. ;x Page 5 of 6 r , s{ Aprii''28;.1995 irr
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