[en] The distribution of environmental tritium in the free water and organically bound hydrogen of trees growing in the vicinity of the Chalk River Nuclear Laboratories (CRNL) has been studied. The regional dispersal of HTO in the atmosphere has been observed by surveying the tritium content of leaf moisture. Measurement of the distribution of organically bound tritium in the wood of tree ring sequences has given information on past concentrations of HTO taken up by trees growing in the CRNL Liquid Waste Disposal Area. For samples at background environmental levels, cellulose separation and analysis was done. The pattern of bomb tritium in precipitation of 1955-68 was observed to be preserved in the organically bound tritium of a tree ring sequence. Reactor tritium was discernible in a tree growing at a distance of 10 km from CRNL. These techniques provide convenient means of monitoring dispersal of HTO from nuclear facilities. (author)

[en] A survey of the deuterium content of precipitation and surface waters across Canada is under way. Precipitation from 15 precipitation stations and river waters from 100 sites are being analyzed every second month for a two year period. Measurements to date show that seasonal variability is not more than ± 2 ppm in surface streams in spite of being up to - 10 ppm in precipitation. Concentrations observed in December 1967 are showm. Concentrations are expressed relative to SMOW - 157.6 derived from recent absolute calibration work in our laboratory.

[en] Two fire tests were conducted at the INEL in December 1978, using both DOT 7A FRP boxes and DOT 17C steel drums. The containers tested were stacked in a configuration simulating the present storage array used at the RWMC. The fire tests revealed that when the DOT 7A FRP boxes were exposed to a small ignition source they would (a) in the WIPP environment, propogate fire resulting in the penetration of the boxes and probable spread of contamination unless fire suppression measures are taken, and (b) in the RWMC environment, probably not propogate the fire through the stack (the fire self extinguished during this test) although the possibility of the box breaching still exists, unless fire suppression measures are taken. The fire tests also revealed that the DOT 17C steel drums slowed the fire spread to the boxes, but that the rigid PVC (polyvinyl chloride) liner contained in the drum is highly combustible and presents an additional hazard. Under these test conditions, it was shown that a box could withstand the fire for at least 40 minutes without penetration, which would allow ample fire fighting response time if the blaze is detected early

[en] In this article we review recent advances in the field of weak decays and consider their implications for quantum chromodynamics (the theory of strong interactions) and electroweak theory (the combined theory of electromagnetic and weak interactions), which together form the ''Standard Model'' of elementary particles. (author)

[en] The Chemical Analysis Group has been approached by a British Scientific instrument maker regarding the possibility of the group participating in a Department of Trade and Industry sponsored scheme whereby we would have a 12 month period to assess the advantages and disadvantages of a new analytical technique, Inductively Coupled Plasma-Mass Spectrometry. This report details our initial assessment of the instrument, carried out in order to decide whether to participate in the scheme. We have attempted to discover whether the instrument meets the claims made of it in advertising literature, and have attempted to compare the technique with another, proven technique, Inductively Coupled Plasma - Optical Emission Spectroscopy. The Plasmaquad offers excellent sensitivity for almost all of the elements of the periodic table, giving a distinct improvement over the Chemical Analysis Group's present capabilities for many elements. The isotope ratio measuring ability is important, as the Group has no such capability at the moment and a demand for this type of measurement is foreseen. Our conclusions, while inevitably somewhat subjective, form the basis for recommending Harwell to participate in the scheme. (author)

No abstract available

[en] Surveys of the concentrations of HT and HTO in the atmosphere downwind of the Chalk River Laboratories reactor facilities were carried out in 1986 November, and in 1989 March, April and September under different conditions of air temperature, wind direction, and snow or vegetative cover. HT usually amounted to 1-5% of total tritium, but values up to 20% were observed, probably resulting from preferential removal of HTO. In all of the surveys, the greater persistence in the atmosphere of HT than of HTO was evident. The existing levels of HT are such that they will not be augmented significantly by chronic releases from the Tritium Extraction Plant (TEP) when it comes into operation. Hence, operation of the TEP will not facilitate studies of the environmental behaviour of chronically released HT. However, longer term studies of the distribution of HT from the existing facilities would be worthwhile. Soil and vegetation HTO levels in the study area are reported. Further studies of the distribution of tritium between the air, soil and vegetation in areas subjected to chronic exposure would be valuable

No abstract available

[en] The electrical transients induced by EMP exhibit unique characteristics which differ considerably from transients associated with other phenomena such as lightning, switching, and circuit malfunctions. The suppression techniques developed to handle more common transients, though not necessarily the same devices, can be used for EMP damage protection. The suppression devices used for circuit level EMP protection are referred to as Terminal Protection Devices (TPD). Little detailed data describing the response of TPD's to EMP-related transients have been published. While most vendors publish specifications for TPD performance, there is little standardization of parameters and TPD response models are not available. This lack of parameter standardization has resulted in a proliferation of test data that is sometimes conflicting and often not directly comparable. This paper derives and/or defines a consistent set of parameters based on EMP circuit hardening requirements and on measurable component parameters and is concerned only with use of TPD's to prevent permanent damage. Three sets of parameters pertaining to pertinent TPD functional characteristics were defined as follows: standby parameters, protection parameters, and failure parameters. These parameters are used to evaluate a representative sample of TPD's and the results are presented in matrix form to facilitate the selection of devices for specific hardening problems

No abstract available