One of the characteristics of the safety control system of the Hanford reactors which is of primary concern from the standpoint of reactor safety is the response time. The purpose of this study is to determine whether the safety control system is sufficiently fast-acting to prevent an intolerably large power excursion from developing. An intolerably large power excursion is one that would cause a melting of the uranium while the reactor power is above the previous operating level. The purpose of this report is to show the techniques used to analyze the speed of control of the Hanford reactors. This report will help to standardize the methods and reduce to a routine the solution of this type of problem. The analog circuits will be presented and explained. A report has been written previously on the speed of control. The changes in the problem have necessitated the redesigning of the analog circuit and also the issuing of this report. This report compiles and organizes the analog work done on the speed of control to date.

This report consists of eight curves, showing Plutonium-240 concentration and conversion ratio as a function of graphite temperature for various goal exposures. A range of 450 to 1000 degrees centigrade on the moderator temperature is used. Other parameters are consistent with the methods and constants used in present product accountability. No attempt has been made to state absolute conversion ratios or Pu-240 percentages. The purpose of this report is to provide a basis for use in economic studies involving changes in graphite temperatures. No conclusions as to operating changes should be inferred from these curves since the combined economics of any change in graphite temperatures include significant and complex factors in addition to conversion ratio and product quality consideration.

During the first two weeks of May while PRTR was being tested at a power level of a few MW, rather large amounts of some fission product gases were observed in the helium system. Samples of D{sub 2}O from the primary cooling system taken during the second week of May were analyzed and found to contain I{sup 131-133-135} and some fission gases (and their daughters) but practically no other fission products. On May 14 the reactor power level was raised to 10 MW and operated at about that level until May 18 at which time the reactor went down. (The power level was actually down to 2 MW for a short period late on May 17, then operated at 15 MW until 1620 on May 18.) On May 17, samples from the primary D{sub 2}O and helium systems were obtained and quantitative analyses of several of the short-lived fission gases and other radioisotopes were performed. Analyses of these samples showed a high concentration of fission gases in the helium system and high I{sup 131} in primary D{sub 2}O system and its ion exchange bed, suggesting possible leakage from a fuel element. Chemical analysis of the primary D{sub 2}O system showed …

A series of fires and explosions in U. S. Atomic Energy Commission facilities handling alpha -active materiais during the last five years resulted in reconsideration of safety problems associated with glove boxes and other equipment used to contain these materials. The literature on construction and operation of glove boxes for work with toxic inorganic materials not requiring biological shielding is reviewed as a contribution to this re-examination, with special emphasis on methods and equipment for working safely with plutonium and other alpha -active materials. An effort was made to point out the direction of current trends in this field. Detailed discussions of glove box designs and methods of experimentation in these enclosures are not included in this report but sufficient information is furnished for finding needed details in the referenced material. Methods for the detection and measurement of alpha -active materials and of impurities in controlled atmospheres are discussed. In addition, the literature on controlled atmosphere enclosures, glove boxes for non- toxic inorganic materials, and the technique of experimenting with such enclosures is reviewed. Some previously unpublished developments are reported. (auth)