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     Here you go Dave:
     
     
     Sandy Perle
     Supervisor Health Physics
     Florida Power and Light Company
     Nuclear Division
     
     (407) 694-4219 Office
     (407) 694-3706 Fax
     
     sandy_perle@email.fpl.com
     
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     RSIC CODE PACKAGE CCC-398
     
     1. NAME AND TITLE
     
     MILDOS: Calculation of Radiation Doses from Uranium Recovery 
     Operations.
     
     2. CONTRIBUTORS
     
     U.S. Nuclear Regulatory Commission, Washington, D. C. 
     
     Pacific Northwest Laboratory, Richland, Washington.
     
     3. CODING LANGUAGE AND COMPUTER
     
     Fortran IV; CDC.
     
     4. NATURE OF PROBLEM SOLVED
     
     MILDOS estimates impacts from radioactive emissions from uranium 
     milling facilities. These impacts are presented as dose commitments to 
     individuals and the
     regional population within an 80 km radius of the facility. Only 
     airborne releases of radioactive materials are considered: releases to 
     surface water and to groundwater
     are not addressed in MILDOS. This is a multi-purpose code system, 
     within the range of its proper application, and can be used to 
     evaluate population doses for NEPA
     assessments, maximum individual doses for predictive 40 CFR 190 
     compliance evaluations, or maximum offsite air concentrations for 
     predictive evaluations of 10
     CFR 20 compliance. 
     
     The MILDOS package includes models for both point sources (stacks, 
     vents) and area sources (ore pads, tailings areas). Gaseous releases 
     are limited to consideration
     of 222Rn plus ingrowth of daughters. Exposure pathways of concern are 
     assumed to be inhalation of airborne radioactive material, ingestion 
     of vegetables, meat, and
     milk contaminated via deposition, and external exposure to radiation 
     emitted by airborne activity and activity deposited on ground 
     surfaces. Liquid exposure
     pathways are not treated by MILDOS.
     
     5. METHOD OF SOLUTION
     
     Emissions of radioactive materials from fixed point source locations 
     and from area sources are modeled using a sector-averaged Gaussian 
     plume dispersion model
     which utilizes user-provided wind frequency data. Mechanisms such as 
     deposition of particulates, resuspension, radioactive decay and 
     ingrowth of daughter
     radionuclides are included in the transport model. Annual average air 
     concentrations are computed, from which subsequent impacts to humans 
     through various
     pathways are computed. Ground surface concentrations are estimated 
     from deposition buildup and ingrowth of radioactive daughters. The 
     surface concentrations are
     modified by radioactive decay, weathering, and other environmental 
     processes. MILDOS allows the user to vary the emission sources as a 
     step function of time by
     adjusting the emission rates; this can include shutting them off 
     completely. Thus, the results of a computer run can be made to reflect 
     changing processes throughout
     the facility's operational lifetime.
     
     6. RESTRICTIONS OR LIMITATIONS
     
     A maximum of 20 sources can be used in a single run.
     
     7. TYPICAL RUNNING TIME
     
     No study has been made by RSIC of typical running times for MILDOS.
     
     8. COMPUTER HARDWARE REQUIREMENTS
     
     MILDOS is operable on the CDC computers.
     
     9. COMPUTER SOFTWARE REQUIREMENTS
     
     A Fortran IV compiler is required.
     
     10. REFERENCES
     
     Giorgio Gnugnoli, Suggested Revision in the use of the MILDOS Code, 
     Memorandum (October 1980).
     
     Giorgio N. Gnugnoli and Dan E. Martin, ``MILDOS Computer Code User's 
     Manual,'' Preliminary document (May 1980). 
     
     D. L. Strenge and T. J. Bander, MILDOS A Computer Program for 
     Calculating Environmental Radiation Doses from Uranium Recovery 
     Operations,
     NUREG/CR-2011/PNL-3767 (April 1981).
     
     11. CONTENTS OF CODE PACKAGE
     
     Included are the referenced documents and a reel of magnetic tape 
     which contains the source code and sample problem input written in 
     EBCDIC card images; total
     records 2780.
     
     12. DATE OF ABSTRACT
     
     February 1982; revised February 1983.
     
     KEYWORDS: ENVIRONMENTAL DOSE; RADIOACTIVITY; AIRBORNE; INTERNAL DOSE; 
     AIR-GROUND