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In the present state of the nuclear art, countries with available water power or supplies of coal and oil will, for some time to come, find it more economic to build and operate conventional power plants.

The authorization of 20,000 kilograms of uranium 235 to be made available for lease to civilian users in the United States was based on estimates of current and future needs. These include the needs of existing licenses and pending applications for licenses as well as proposals received by the Commission—including proposals under the Power Demonstration Reactor Program—which seem likely to lead to the filing of license applications during the current fiscal year ending June 30, 1956.

Only part of the special nuclear material will be distributed in any one year. Licenses may be issued for a varying period extending up to 40 years, and delivery of uranium 235 to licensees will be spread over the life of the licenses, to permit start-up of reactors and replacement of fuel as required in later years.

The uranium 235 will be distributed under provisions of Section 53 of the Atomic Energy Act of 1954 and will be allocated to specific licensees only on the basis of a Commission determination of the licensee's need for the material.

The procedures which will govern the distribution of the 20,000 kilograms of uranium 235 to be made available to other countries, as well as charges for sale or lease, will be announced in the near future. However, based on the value of $25 per gram of contained uranium 235 for enriched uranium leased for research reactors, as announced by the U. S. Atomic Energy Commission at the International Conference on the Peaceful Uses of Atomic Energy, the 40,000 kilograms of uranium 235 now made available for such sale or lease would have a value of one billion dollars.




be Research has been conducted in the


Protection of the public health and Fallout predictions are dependent safety is a primary consideration in the upon the accuracy of weather informaconduct of the nuclear tests which will tion. The weather reporting network begin in the spring of 1956 at the which will be utilized for the 1956 tests Eniwetok Proving Ground.

will be larger than those in effect durVarious precautions have been taken ing any previous operation. Additional to keep significant radioactive fallout surface and upper air observing stawithin the confines of the danger area

tions have been established, and imin the Pacific which was announced on proved equipment and techniques have March 1, 1956. With the exception of been developed to increase the altitude Joint Task Force facilities, there are and improve the accuracy of weather no inhabited places within the danger observations. As a result, more com

plete and earlier weather information There is no reason to expect that

will be provided. hazardous fallout will occur outside the danger area, and it is highly unlikely special field of tropical meteorology, that any inhabitants of atolls will have and weather observers and forecasters to be mored. However, complete plans

have been instructed in the have been made for transportation of methods of forecasting which have been the inhabitants should such action have developed as a result of these studies. to be taken.

Trained personnel have been organElaborate systems have been estab-ized into a fallout prediction unit. lished to detect and measure radioactiv- They will utilize newly-developed fallity in the vicinity of the Proving out computers, will assist in predicting Ground, in the United States, and in fallout patterns by mechanizing most other parts of the world. In addition, of the mathematical procedures inextensive marine surveys will be con

volved. Use of the computers is exducted to measure radioactivity in sea pected to allow forecasts to be made water and marine organisms.

much more rapidly than heretofore, so More detailed information on health that the final decision to conduct or and safety measures relating to the postpone a test can take last-minute test series follows:

weather observations into account."

Models of the clouds produced by largeFALLOUT PREDICTIONS

1 The fallout computer, designed by the

National Bureau of Standards, works in the Tests will be conducted only when

following way: the forecast pattern of significant fall

Weather information and estimates of the out is entirely within the danger area, diameter and height of the cloud and the in which there are no inhabitants. In distribution of radioactivity within the cloud forecasting fallout patterns, scientists

are fed into the computer by setting various

dials. One-twentieth second after the data will make use of improved methods of is set up, the machine visually displays a precollecting and evaluating data which dicted fallout pattern on the face of a telehave been developed as a result of in- | vision-like tube. The predicted radioactive tensive study of the problem of pre

intensity at any point up to 250 mlles or

more from ground zero is indicated by the dicting fallout in the vicinity of the brightness of the pattern at the particular Proving Ground.

point in question.


scale nuclear detonations have been de- Regular air and sea searches of the veloped as result of experience area will be conducted in advance of gained from the 1954 testing operations, the start of operations. Before each and these also are expected to improve shot, the patrol of the danger area will fallout predictions.

be intensified, particularly in the area With better weather information, where fallout is forecast. more accurate cloud models, and faster procedures made possible by computing RADIATION MONITORING IN machines, the fallout prediction unit PROVING GROUND REGION will be able to make much more rapid and accurate forecasts of fallout pat- After each detonation, aircraft will terns than was possible two years ago. track the radioactive cloud. In addi

tion, aircraft using aerial monitoring Tests will be conducted only when

equipment will survey populated areas significant fallout is predicted entirely

south and east of the Proving Ground within the danger area.

to detect any radioactivity on land

masses and on the surface of the sea. ENERGY RELEASE OF

Radiological safety personnel, DETONATIONS

equipped with radiation detection and

measuring instruments and two-way As announced on March 1, 1956, the radios to enable them to communicate 1956 tests will involve weapons gen- with the central Task Force Radsafe erally smaller in yield than those tested Office, will be stationed on the nearby during the 1954 series. The energy inhabited atolls to the east and south release of the largest 1956 test is ex- of the Proving Ground, and at weather pected to be substantially below that of stations of the weather reporting netthe maximum 1954 test.

work. In the unlikely event of sig

nificant fallout in an inhabited area, DANGER AREA

the monitors would warn the inhabi

tants and advise and assist them in The danger area is generally rectan- taking safety measures. The monitors gular in shape and comprises roughly also will train Marshallese medical 375,000 nautical square miles. Its practitioners and health aids in basic boundaries were announced on March emergency measures. 1, 1956. While slightly smaller than

danger zone used in the latter part EMERGENCY PLANNING of the 1954 series, the area is many

As a result of the monitoring protimes larger than the initial danger

cedures described above, the Task Force area used in 1954, and has been reoriented slightly for increased safety. wind shift carry the cloud toward an

will have warning should an unexpected Outside of the test facilities, no in- inhabited area, and also will receive habited atoll is within the area.

information by radio on the levels of All ships, aircraft and persons have radioactivity on the inhabited atolls. been cautioned to remain clear of the It is not expected that there will be danger area by notices which have been need to move any of the inhabitants at given the widest possible distribution any time during the test series. How. through United States and interna- ever, as a precaution, complete plans tional marine and aviation organiza- have been prepared for transporting tions. The Department of State has persons from populated atolls in the notified all Diplomatic Missions in event that such action were considered Washington of the extent of the area. advisable.






Outside of the testing area, the The heavier particles fall out of the detonations are not expected to produce radioactive cloud at early times after levels of radioactivity in the ocean a detonation, while their radioactivity which would be hazardous to marine is still high. Therefore, the highest life or to persons eating food fish. | levels of radioactivity occur over However, an extensive program of local area downwind from the point measurements of radioactivity in the of detonation. The area of significant sea water and in marine organisms will fallout is expected to occur entirely be conducted.

within the uninhabited danger area surBeginning about June 10, a fast U. S. rounding the Eniwetok Proving Navy vessel will work westward from Ground. the test site, making sweeps between As the radioactive cloud is trans10 and 14 degrees North latitude west ported away from the point of detonaas far as fallout radioactivity can be tion, it is widely dispersed by air detected.

currents and diluted by normal air. Its Continuous readings of radioactivity radioactivity also decreases rapidly bein the surface water will be taken by cause of the normal process of radiomeans of a device which pumps water active decay. By the time the cloud around a detection instrument in a tank from an Eniwetok test has traveled on the deck of the ship. The ship will eastward across the ocean, it will have stop each 25 miles to take samples of become a dispersed, invisible air mass, the water at the surface and at depths which has lost much of its original of 25, 50, 75 and below 100 meters. radioactivity.

Personnel aboard the ship also will As a result, the levels of radioactivity make tows for plankton-tiny marine in the United States from the Eniwetok organisms which tend to concentrate tests are expected to be low. Levels of radioactive materials in their tissues. | 10 or more times the normal backFish will be caught, and analyzed for ground may be reached in some localradioactivity.

ities at some times. However, these inAfter the series, when test radioac.creases in background will be tempotivity will have moved further away rary, and will result in exposure far from the test site, a similar survey will below amounts which would affect the be carried out as far west as radioac- health of exposed persons. tivity can be detected.

As it has in the past, the CommisThe Commission also has entered into sion will conduct extensive radiological a contract with the George Vanderbilt monitoring operations within the Foundation at Stanford University, United States during the test series. under which scientists will collect sam- These operations are not conducted in ples of water, plankton, marine inverte- the expectation of possible hazard, but brates and fish in the vicinity of the for scientific purposes and to keep the Palau Islands. These samples will be public informed on levels of radiosent to the biological laboratory at the

activity. Hanford Works for analyses.

In addition to these investigations, Radioactive fallout consists of a mixture land and marine biological surveys will of radioisotopes, with varying half-lives.

The mixture as a whole decreases in radiobe conducted on Eniwetok and Bikini activity in such a way that for every seven Atolls and in their lagoons. Samples of fold increase in age, the total radioactivity water, lagoon life, and animal life on is decreased 10-fold. Thus, the radioactivity the atolls will be collected and analyzed one-tenth that at one hour, and in 49 hours

at seven hours after the explosion is only for radioactivity.

is one-hundredth, etc.

Two types of monitoring operations San Francisco, Calif. will be conducted within the United San Juan, P. R. States. One will consist of a network Scottsbluff, Nebr. of U. S. Weather Bureau stations, Seattle, Wash. which collect fallout samples at selected Tucson, Ariz. locations throughout the nation. The Washington, D. C. (Silver Hill, Md.) collection method is simple. A sheet of Wichita, Kans. film covered with an adhesive is ex

This collection system does not proposed outdoors on a tray for 24 hours, vide immediate information on dose and then is mailed to the Commission's rates, since the samples must be mailed New York Health and Safety Labora

to the Health and Safety Laboratory tory. There, the sample is reduced to and counted there. However, the inashes, and the ashes are monitored formation collected has varied scientific with sensitive laboratory instruments. Very minute amounts of radioactivity to compute and record the overall ac

uses. It is needed by the Commission can be measured by this technique.

cumulation of radioactivity as a result During the 1956 series, the following of tests. It is needed by the photuWeather Bureau stations will make graphic industry and by scientists confallout collections :

ducting experiments with low-level Albuquerque, N. Mex.

radiation, since these activities can be Atlanta, Ga.

affected by even a very slight increase Billings, Mont.

over the normal background. The data Binghamton, N. Y.

also are used by meteorologists to trace Boise, Idaho

air masses and check predicted trajec. Boston, Mass.

tories. Chicas Ill.

More rapid information on radiation Cincinnati, Ohio

levels will be provided by 39 monitorCleveland, Ohio

ing stations located in cities across the Concord, N. H.

country. Corpus Christi, Tex.

Twenty-seven of these stations have Dallas, Tex.

been set up by the U. S. Public Health Des Moines, Iowa

Service, which has been furnishing fallDetroit, Mich.

out monitoring services to the CommisGrand Junction, Colo.

sion for the past two years in States Hatteras, N. C.

near the Nevada Test Site. At the Jacksonville, Fla.

Commission's request, the Public Knoxville, Tenn.

Health Service has established an exLas Vegas, Nev.

panded monitoring program which will Los Angeles, Calif.

be in operation with the forthcoming Louisville, Ky.

test series. Medford, Oreg.

The monitoring stations established Memphis, Tenn.

by the Public Health Service will collect Miami, Fla.

daily readings of radioactivity and forMinneapolis, Minn.

ward the data to a central collection New Haven, Conn.

office in Washington. The monitoring New Orleans, La.

stations also will report data to the New York (La Guardia), N. Y.

State Health Officers of the States in Philadelphia, Pa.

which the stations are located. Pittsburgh, Pa.

The primary purposes of the network Rapid City, S. Dak.

are to give State and local health de Rochester, N. Y.

partments more experience in studying St. Louis, Mo.

fallout and normal background radiaSalt Lake City, Utah

tion levels, and to obtain daily records

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