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Following many years of productive research, the 184-inch Cyclotron, the SuperHILAC, and the BEVALAC accelerators at the Berkeley Laboratory were closed, leaving thousands of concrete shielding blocks available for reuse, recycling, or disposal. The process history of these blocks precludes free release pending radiological characterization. This paper describes a procedure whereby a high efficiency shielded germanium spectrometer is used to rapidly characterize natural and man-made activity within the blocks. The spectrometer is moved up to the block and 5 minutes of data are collected at the point on the block that registers highest on a micro-R meter. Sensitivity is better than 1 pCi/g (0.037 Bq/g) for Co-60 and Eu-152, the prominent man-made activities observed. One-time calibration of the detector system is obtained from a sample of concrete, drilled with a hammer drill, counted in our low-background facility, and compared to crashed rock with known U, Th, and K activity. A simple relationship exists between the counts/minute observed in a characteristic gamma-ray peak and the activity in the block.

A direct statistical method has been applied to determine the effect of uncertainties in rate coefficients on computed densities of E region species. Uncertainties in rate coefficients are described in terms of Gaussian error law distributions with a common fractional standard deviation. Mean densities are found to be relatively insensitive to rate coefficient uncertainties; fractional standard deviations of density distributions are, in general, less than twice those associated with rate coefficient distributions, provided the fractional standard deviations of the rate coefficient distributions are not greater than 0.45. Many reactionsare necessary to describe chemical proces•ses in the atmosphere. In such chemical systems it is difficult to evaluate inaccuracies in the computed species densities. These inaccuracies stem from uncertainties in the input data and from omissions or approximations of relevant physical and chemical processes. One of the uncertainties, that associated with reaction rate coefficients, is treated here by a direct statistical method for the case of an E region chemical reaction system operating over short time intervals. The calculations presented here are meant to be illustrative rather than exhaustive. Sufficient information about the errors and the distribution of errors associated with measurements of rate coefficients is not generally available. Accordingly, in the calculations described here, uncertainties in the rate coefficients were assumed to be describable in terms of the Gaussian error law with a mean value of the rate coefficient ko and a standard deviation s; the effects of variations in s on species densities and their distributions were examined. For simplicity a common fractional standard deviation was assigned to the rate coeffici6nt distributions. Consider a system consisting of n reactions and corres. ponding rate coefficients; let m(

A B S T R A C T ' ( u nllr,. ue op ,r-et .~~' side tI ,,c~ ,''.~ar, ,,n(f i d c n t , fy ht b l o c k nun,bet)A preliminary model of the ambient atmosphere and ionospher e has been adopted for use in ROSCOE . The model provides at all altitudes all the needed properties of the neutral atmosph ere , including a dependence on the solar cycle and the local (apparent) t ime for altitudes above 120 km . Analytic fit-functions to My er ' s minor-species data base provide all the minor neutral species ( 0, C0~, N , NO , H~O , O 2 (1 A g ) , 03 , and NO~) required by _ . 2~~~+ DD ~~~~~~~ E D I T I O N OF I NOV 55 IS O B S O L E T E UN CLAS SIFIED S E C U R I T Y C L A S s I r I r A T I~~N OF T H I S P A G E ( B?,e ,, Defe F n l e , e I ) -j UNCLASSIFIED S E C U R I T Y C L A S S I F I C A T I O N OF THIS PAGE(lThen Data Entered)18. SUPPLEMENTARY NOTES (Continued) EDITORS ' NOTE Volumes 13 to 17 were originally published by SAl to describe the atmospheric , geomagnetic , and high-altitude energy deposition and neutral heave models for ROSCOE . This whole section of code , when associated with an appropriate DRIVER subroutine , operated as a package that ran independently of the rest of the ROSCOE structure . Provision was also made , within this high-altitude package , for two comp letely independent descri ptions of atmospheric heave , each with its own descri ption of atmospheric chemistry .When CRC incorporated this section of code within the ROSCOE framework , some modifications were necessary , which means that some of the descriptions in Volume s 13 to 17 are inappropriate to ROSCOE as it now exists. In particular , the NRL heave routines (deck NRLHYD) and associated chemistry (deck NRLCHM) are not presentl y used in ROSCOE . Three other subroutines are different: subroutines ATMOSU , ElF , and XTCOEF correspond to the ROSCOE subroutines ATMOS , EXP INT , and WDXP respectivel y. With these exceptions , the subroutines described in Volumes 13 to 17 correspond exactl y to those currently in ROSCOE .20. ABSTRACT (Continued) .the chemistry module. Interim electron density profiles and effective ion production rates serve as the basis for the ionospheric model. Herein are presented derivations , flow diagrams , Fortran listings , and test problems . In this volume we describe the model for the major and minor neutral species in the ambient atmosphere and the ambient ionosphere For simplicity in presentation , we have adopted flexible definitions of which species are major and which are minor. It is anticipated that the meaning will always be clear to the reader in the context of the usage.The overall inputs , some intermediate outputs , and final outputs for Model 1 are given in Table 1.A flow diagram of the 11 subroutines , with thei r driver routine for developm ent and test problem , is given in Fi g. 1. A brief , simplified descri ption of the working of the 11 subroutines follows.The subroutine ATMOSU is initialized on a call to ATMOSU( 1, 8_ The three major subroutines are read y for use after they hav e b...

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