United States
                   Environmental Protection
                   Agency
Office of Radiation and Indoor
Air(6603J)
Office of Solid Waste and
Emergency Response (5101)
9355.0-50FS
EPA/540/F-94-022
PB 94-963306
January 1996
                   Fact Sheet:   Computer Models
                   Used  to Support Cleanup
                   Decision Making at Hazardous
                   and Radioactive Waste  Sites
                                                              Quick Reference Fact Sheet
BACKGROUND
Mathematical models that characterize the source,
transport, fate, and effects of hazardous and radio-
active materials are used to help determine cleanup
priorities and select remedial options at sites con-
taminated with radioactive materials.

A joint Interagency Environmental Pathway Mod-
eling Working Group has been established by the
EPA Offices of Radiation and Indoor Air (ORIA)
and Solid Waste and Emergency Response (OSWER),
the DOE Office of Environmental Restoration and
Waste Management (EM), and the Nuclear Regula-
tory Commission (NRG) Office of Nuclear Material
Safety and Safeguards (NMSS). The purpose of the
Working Group is to promote the appropriate and
consistent use of mathematical environmental mod-
els in the remediation and restoration of sites con-
taminated by radioactive substances.

The Working Group has published reports intended
to be used by technical staff responsible for identify-
ing and implementing flow and transport models to
support cleanup decisions at hazardous and radio-
active waste sites. This fact sheet is one of a series of
fact sheets that summarize the Working Group's
reports.

REPORT
Purpose
The EPA, DOE, and NRC joint program spon-
sored a mail survey in 1990 and  1991 to identify
radiologic and  nonradiologic  environmental
transfer or pathway computer models that have
been used or are being used to support cleanup of
hazardous and radioactive waste sites. The intent
of the survey was to gather basic administrative
and technical information on the extent and type
of modeling efforts being conducted by EPA,
DOE, and NRC at hazardous and radioactive
waste sites, and to identify a point of contact for
further followup.

Contents of Report
The report includes an introduction, description of
the survey and model classification scheme, survey
results, conclusions, and references. The appendix
contains descriptions and references for the models
reported in the survey.

The raw data from the questionnaire are compiled
in tables. Table 1 lists the names of the respondents,
their organizations, addresses, phone numbers, and
models used. Table 2 provides an alphabetical list of
models, model types, and references. Table 3 in-
cludes the model, site type, contaminant, endpoint,
level-of-effort, validation (yes/no), and publication
information. Table 4 summarizes the organizations
that sponsored development of the  reported mod-
els. Table 5 provides an index of existing environ-
mental pathway models.

Method
Questionnaires were widely distributed to approxi-
mately 550 persons within the three sponsoring
agencies, national laboratories, universities, and
consulting engineering firms.

The report presents a database of user model /infor-
mation pertaining to each model, including:

• Site type
• Sponsoring agency
• Media/category
• Level of effort

-------
• Validation/calibration
• End points
• Publications

Findings
Eighty-seven persons responded to the survey, rep-
resenting a response rate of 16 percent. Individuals
responded from 38 different companies, facilities,
or agencies.  The  respondents were responsible
primarily for DOE sites. More than 75 percent of
the reported site types were DOE-related.

Respondents reported using 127 different computer
models. Most were developed by or for the EPA,
DOE, or NRC, but a substantial number (24 percent)
were sponsored by other groups such as  private
corporations, universities, and other government
agencies. The overwhelming majority of models are
being used for the more general purpose of finding
environmental concentrations of contaminants and
radon dose commitments. Some other uses include
risk assessment, water levels, flow rates, riprap
sizing, and radon emanation.

The  reported models were  classified  by  the
environmental media they  simulate and by their
major purpose (see table on page 3). Models related
to multi-media environmental pathways constituted
the largest category of models in use by respondents
with 41 models reported.   Multi-media  models
integrate several media (e.g., air, ground water,
           food chain, soil) into one simulation. Respondents
           reported using 34 different ground-water transport
           models, 20 air models (which sometimes included
           related soil deposition and agricultural uptake
           parameters),  and 19 engineering models, which
           included performance assessment, accident, and
           radiation dose models. Seven surface water transport
           and five geochemical models also were reported.
           The geochemical models were often used to predict
           the relative abundance or concentration of various
           contaminant species, to determine  whether a
           dissolved pollutant will precipitate during transport
           in surface or ground water, or to determine whether
           a solid pollutant might dissolve  under certain
           aqueous conditions.

           Based on a compilation of known environmental
           pathway models (extrapolated from the published
           literature and reviews) the models reported in the
           survey represent approximately 25 percent of known
           models used  in environmental pathway analyses.
           Whether the  models not identified in the survey
           are actually being used to support cleanup deci-
           sions could not be answered due to the relatively
           small number of respondents. The report recog-
           nizes the dynamic nature of model development
           and application.

           Approximately 60 percent of the identified models
           in the survey were used at only one site. Only a few
           models appeared to be used across a large number
           of sites.
          Major Types of Environmental Computer Models Reported in Use
                 Multt-  Ground-
                 media   Water
                         Transport
Air  Engineering  Surface  Geo-    Utility
                  Water  chemical
               Traneport

-------
Models in Use Identified in Survey
" "i *^i li
SdMoongCal
AFTOX
AIROOS(-EPA.-PC)
ARa
BALANCE
BARRCR
Beet* Propriety
BOTRAN
BRUNZOG
CAP-88
CASCADER
CFEST
CHARM
COMPLY
CONOOS-II
CONSOL
CREAMS
CYLSEC
OARTAB
DCM30
OECHEM
OECOM
DTTTY
DOSES
DOSTOMAN
DFCT
E03*
FLASH/FLAME
FLOWPATH
aOWTHHOUGH
FT WORK
GCDT30H
GENK
GENMOD
GEOROW
GWFLOW
HifMI •
rTnrWr™*
HEC-1.-2
HELP
HRS-1
HSPF
HYDROGEOCHEM
IMPACTS (PART61M-BRC)
NPUFF
ISCST/ISCLT
tSOSHLD(-l)
LTSAMP
MACCS
MAT1230
MEPAS
MESOI
MILDOS (-AREA)
MINTED (-A1.—A2)
ML CODE



•






•









•
•
•
•
•





•
•
•
•





t


•


•



•

•



•
•




•

•


•
«
•



•

















•






•
•

•



•


•
















•




















•


•











•







•




•




•


•





t

•
•





•
•












•





\




•





















•














•










•

V ' *V \J V





•


•






•











•










•






•

•









































•



•


t






•






•

•
•



•

•













•











•



•










•




•

•

•





•
•

•
•
•

•
•
•
•
•
•






•
•






•

•


•

•

•
•
•

•

MOC
MOD3D
MOOROW
MT30
NEFTRANII
NEWBOX
NUREG-0707
OOAST
OORECH6.7
ONSITE/MAXI1
PAGAN
PATH
PATHRAE EPA. HAZ. RAO
PATHRISK
PC-SLOPE
PHREEOE
PLASM
PORRO-3
PORMC-3
PRESTO-II EPA. CPG. POP
RAECOM
RADRtSK
RANDOM WALK
RASCAL
RESRAO
RETC.F77
RHRS-LC
RSAC-3
SBUHYD
SCREEN
SEFTRAN
SFRPE
SMS
SOL
SOLUTE
SOURCE 2
SPUR
STABL.STABL5
STABR
STEPH
STRP1B
SUMO
SWFT(ILNI)
TARGET
TDRECH
TEMPEST/FLESCOT
THEM
TOUGH
TRACR30
UDAD
UNSAT-2 (-H)
UTEXAS2
UTV
VAM20I-30)






*

•
•
•
•
•
•





•




•

•









•



•
•


•




•


•





















•
•





•

•


•

















































•
















•








•
•
•
•



•








•
•
•



•


•




•


•
•







•




•
•

•


•















•











































•



•
•



•








•



•



•





•
•
•











•









•


















•







•



















•
•
•
•











•


























•




•
•

•


•
•





•


•

•
•




•
•
•
•
•

•
•

•
•







•






•




•
•
•


•
•

-------
CONTACTS
If you have any questions or want a copy of this or
other reports, contact:

Beverly Irla, Project Manager
Office of Radiation and Indoor Air (6603J)
U.S. Environmental Protection Agency
401 M Street, SW
Washington, DC 20460
(202) 233-93%

Paul Beam
U.S. Department of Energy
Office of Environmental Restoration
EM-451/CLOVBLDG
19901 Germantown Road
Germantown, MD 20874-1290
(301)903-8133

Sam Nalluswami
U.S. Nuclear Regulatory Commission
Office of Nuclear Material Safety and Safeguards
(T-7F27)
Washington, DC 20555
(301)415-6694
Superfund Hotline
U.S. Environmental Protection Agency
Office of Solid Waste and Emergency Response
401 M Street, SW (5203G)
Washington, DC 20460
(800) 424-9346

REPORTS
Computer Models Used to Support Cleanup Decision-
Making at Hazardous and Radioactive Waste Sites, EPA
402-R-93-005, March 1993. Also available from the
National Technical Information Center (NTIS), (703)
487-4650, PB93-183333/XAB.

Environmental Characteristics of EPA, NRC, and DOE
Sites Contaminated with Radioactive Substances, EPA
402-R-93-011, March 1993. NTIS,PB93-185551/XAB.

Environmental  Pathway Models — Ground-Water
Modelling in Support of Remedial Decision-Making at
Sites Contaminated with Radioactive Material, EPA 402-
R-93-009, March 1993. NTIS, PB93-196657/XAB.

Technical Guide to Ground-Water Model Selection at
Sites Contaminated with Radioactive Substances, EPA
402-R-94-012, September 1994. NTIS, PB94-205804/
XAB.

-------