AirWare: urban air quality
assessment and management
The Industrial Source Complex Model (ISC) is a multiple
point sources and area source model developed by the
US Environmental Protection Agency, EPA.
It is one of the UNAMAP guideline models.
ISC is also one of the central models in the
air quality management information system.
ISC is a
Gaussian plume model that can describe individual episodes of a
few hours or long-term, eg., annual, average conditions.
A basic assumption of the Gaussian model is steady-state conditions, ie.,
both the emissions and the weather conditions in terms of wind speed,
directions, air temperature, stability class, mixing height, and
precipitation, are assumed constant.
ISC (Industrial Source Complex Model) has been specifically developed
to simulate air pollution due to an industrial plant, taking accurately
into account the effect of high stacks on the behaviour of the
pollutant plume. It may be applied in urban or rural environment
with a moderately complex terrain. Its numerous options allow
to compute the dry deposition of the pollutant downwind the stacks,
to model the plume hight accounting for the hydrodynamical effects,
to simulate the impact of linear, area and volumetric sources.
It works with non reactive pollutant, including particulate matter,
but may include a first order decay.
The program has two versions. In the long term version (ISC-LT),
it computes average concentration values on an area of few hundred
square kilometers for a period like a season or a year, on the
basis of the correspondent meteorological data. The short term
version (ISC-ST) computes mean concentration values for a period
of one or few hours.
Curtis P. Wagner
TRC Environmental Consultants, Inc.
800 Connecticut Boulevard
East Hartford, Connecticut 06108
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USAEC report ATDL-106. U.S. Atomic Energy Commission, Oak Ridge,
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Nuclear Safety, 17: 68-86, 1976. EPA-450/2-78-027R, GUIDELINE
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of a rectangular-shaped building on dispersion of effluents from
short adjacent stacks", A.E. Vol.16, 1982;
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turner workbook values", EPA publication no. EPA 600/4-76-030b.
U.S.Environmental Protection Agency, research triangle, park,
- D.B.Turner,"WORKBOOK OF ATMOSPHERIC DISPERSION ESTIMATES",
PHS Publication No. 999-26. U.S. Environmental Protection Agency,
Research Triangle, Park, NC, 1969;
- J.F.Bowers, A.Anderson, "An Evaluation Study for the
Industrial Source Complex (ISC) Dispersion Model", EPA Publication
No. EPA-450/4-81-002, 1981;
- J.F.Bowers, A.Anderson, W.R.Hargraves, "Tests of the
Industrial Source Complex (ISC) Dispersion Model at the Armco
Middle-town, Ohio Steel Mill", EPA Publication No. EPA-450/4-82-006,
- J.S.Scire, L.L.Schulman, "Evaluation of the BLP and ISC
Models with SF& Tracer Data and SO2 Measurements at Aluminum
Reduction Plants", Air Pollution Control Association Specialty
Conference on Dispersion Modeling for Complex Sources, ST. Louis,