The U.S. Environmental Protection Agency and Oak Ridge National Laboratory have developed an online calculator called the Vapor Intrusion Screening Level (VISL) Calculator. The calculator provides screening level concentrations for groundwater, soil gas, and indoor air for certain chemicals to help risk assessors evaluate vapor intrusion risks. It calculates screening levels for groundwater and soil gas using conservative attenuation factors from EPA's draft vapor intrusion guidance document. The VISL Calculator can also estimate indoor air concentrations from user-entered soil gas and groundwater data using default attenuation factors. It will provide risk values and be a useful tool for citizens, risk assessors, and risk managers.

1. SubmittedVISLAbstract
Control/TrackingNumber:2016-A-3674-SOT
Activity:Abstract
CurrentDate/Time:10/7/2015 8:30:09 PM
AuthorBlockLeslie Galloway1,FredDolislager1,Stephine Smith2,AliciaM.Frame3, LindaG. T.
Gaines3
1The Institute forEnvironmental Modeling,The Universityof Tennessee,Knoxville,Knoxville,
TN,2The Universityof Tennessee,Knoxville,Knoxville,TN,3Office of SuperfundRemediation&
TechnologyInnovationSciencePolicyBranch,EnvironmentalProtectionAgency,Washington,
DC
Web-basedCalculatorforVaporIntrusionScreeningLevels(VISL)
Abstract:
The U.S. Environmental ProtectionAgencyOfficeof RemediationandTechnologyInnovation
(OSRTI),throughaninteragencyagreementwithOakRidge National Laboratory(ORNL), has
developedanonline calculatorforvaporintrusionscreeninglevels(VISL).Thistool provides
screeninglevel concentrationsforgroundwater,soil gas(sub-slabandexterior),andindoorair
for certainqualifyingchemicalstoassistriskassessorsindeterminingrisksdue tovapor
intrusion.The screeninglevelsforgroundwaterandsoil gas(eithersub-slabgasorsoil gas
collectedbeloworadjacenttobuildings) are calculatedfromthe targetindoorair
concentrationsusingempirically-basedconservative “generic”attenuationfactorsthatreflect
generallyreasonableworst-caseconditionsasdescribedinthe EPA’sdraftvaporintrusion
guidance (EPA 2002). The default,genericVISLsare basedondefaultexposure parametersand
factors thatrepresent ReasonableMaximumExposure (RME) conditionsforlong-term/chronic
exposures.Inadditiontocalculatingscreeninglevels,thistool canestimate calculateindoorair
concentrationsfromsoil gasandgroundwaterconcentrationsenteredbythe userandgeneric,
empirically-derivedattenuationfactors. Inaddition,riskvaluesfromindoorairconcentrations
and user-providedexposure parameterscanbe calculated.Thisnew tool will be useful for
concernedcitizens,riskassessorsandriskmanagers.