with the character of the terrain, but must ordinarily be supplemented by ground surveys. Aerial surveys have been used success fully to locate areas in which the occurrence of uranium ores appeared probable and was later confirmed by ground exploration.

Periodic aerial surveys of areas known, or likely, to contain uranium or thorium ores can readily discover the existence of mining operations. Ground inspection would be required to determine the products of

the mines.

Aerial surveys are particularly useful for determining the existence or non-existence of industrial installations in an area in which clandestine activities are suspected. The interpretation of aerial photographs of highly industrialized areas is more difficult than in the case of nonindustrial areas, but may be a fairly reliable guide in either case. Aerial photographs give considerable information about the general character of the operations conducted in an installation: power requirements; water requirements; and the flow of raw materials and products. However, direct ground inspection is necessary to determine accurately the character of the operations.

New installations, or extensive modifications in existing installations, are readily detected by comparison of aerial photographs taken at successive intervals. Camouflage is not very effective against photographic aerial survey, but makes it difficult to determine the nature of the installations under observation.

6. Ground surveys are a useful means for the detection of clandestine operations; under certain conditions, the right to conduct such surveys is essential.

The principal objectives of ground surveys would be to locate mines and large industrial buildings, to conduct geological surveys, to make physical measurements useful in locating clandestine activities such as seismic measurements to detect blasting, and to sample materials for radioactive elements.

In crowded, built-up areas, ground surveys will ordinarily provide a satisfactory and reasonably convenient means for determining the existence or non-existence of operations which warrant direct inspection. Generally speaking, investigation by ground parties would be likely to pick up less irrelevant information than investiga tion by aerial surveys. Moreover, certain types of installation cannot be investigated adequately from the air. Examples range from underground structures and installations located in densely wooded areas to ordinary industrial buildings which may be detected with ease, but without reliable indication of the activities involved. Direct inspection may not be required if ground investigation discloses no basis for suspicion.

Ground surveys can be conducted with maximum efficiency if aerial surveys are available as an indication of the areas and installations which warrant attention, as well as the areas which can be ignored without appreciable risk.

The right to conduct ground surveys is essential, but should be subject to appropriate restrictions similar to those required for inspec tion.

7. Safeguards against the dangers of clandestine mining would be provided by the right of inspection coupled with air and ground surveys based on adequate geological knowldege. Neither air survey nor ground

survey alone provides adequate information; both are essential, and they must be used in combination.

All available geological knowledge, whether acquired directly or indirectly, is needed by the international control agency to determine the areas to which air and ground surveys should be directed for the detection of possible clandestine mining and milling. Aerial surveys of such areas, which should be provided for in accordance with finding 5, will ordinarily reveal any unreported operation, or changes in a known installation, but will not usually indicate the character of the operations. Ground surveys may be required in areas not readily evaluated by aerial photography, e. g., heavily wooded areas

or caves.

It is assumed that all declared mines producing uranium or thorium would be under controls designed to prevent the diversion of these materials. All other mines would have to be inspected at appropriate intervals to make sure that they did not produce uranium or thorium as by-products, except where the geological formations exclude the possibility of uranium or thorium deposits.

In areas where the occurrence of uranium or thorium is known or probable on the basis of geological information, periodic aerial surveys could provide an adequate check on the existence of unreported mining operations. However, the character of these operations could only be determined by inspection at the mine and sampling of the ore and the products from the mine.

The detection of suspected clandestine mining operations might, on occasion, be facilitated by inspection of transportation facilities and materials being transported to or from areas known, or likely, to contain uranium or thorium deposits. In some cases the means of transportation required for unreported operations located in remote areas would provide an indication of the existence of activity of an unknown character. In cases involving transportation by water or by hydroplane, the usefulness of this method of detecting possible clandestine activities may be quite limited.

8. Clandestine refineries and chemical and metallurgical plants may not differ from conventional chemical processing plants to a degree which would aid in their detection.

Plants for the chemical and metallurgical treatment of uranium and thorium concentrates need not be so large as to attract attention. While the existence of these plants could probably be detected by aerial surveys if they were conducted, there would be little to indicate that they were engaged in clandestine operations. However, these plants alone would not constitute a serious threat, since their product would have to be fed into isotope separation plants or reactors which do have distinguishing characteristics.

9. The detection of clandestine bomb manufacture as such is almost impossible; it is therefore vital that any unauthorized accumulation of essential nuclear fuels be prevented.

Plant installations for the manufacture of bombs are small compared with those required for the production of nuclear fuels, and they have no distinguishing features to facilitate detection. As long as bomb design requires an unusual quality and variety of research personnel, the activities of such personnel might indicate where bombs

were being produced clandestinely; however, once the design of atomic weapons had been developed, the need for scientific personnel would be reduced, and the value of a knowledge of the activities of key personnel would therefore be slight. Because of the difficulties in detecting clandestine bomb manufacture and because of the extremely short time and small facilities required to produce the bomb if the necessary fissionable material is available, it is essential that stringent safeguards be taken at earlier stages. Accordingly, the prevention of clandestine bomb manufacture must begin with the establishment of safeguards against diversion and clandestine production of raw materials and must be applied at all stages in the production. and use of fissionable material.

Summary

A. The international control agency will require broad privileges of movement and inspection, including the rights to conduct surveys by ground and air. These privileges should, however, be very carefully defined to ensure against misuse.

B. Reports and returns on relevant matters will be required from national governments.

C. The international control agency should co-ordinate all relevant information to determine what areas may be suspected of containing clandestine activities.

D. Isotope separation plants, reactors, and chemical extraction. plants, as well as mines, have distinguishing features which would facilitate the detection of clandestine activities at those stages.

E. Detection of clandestine refineries and chemical and metallurgical plants is more difficult than detection of clandestine operations at other stages in the processing of nuclear fuel.

F. The detection of clandestine bomb manufacture as such is almost impossible; it is therefore vital that any unauthorized accumulation of essential nuclear fuels be prevented.

CHAPTER 7-SAFEGUARDS AGAINST THE SEIZURE OF ATOMIC ENERGY ESTABLISHMENTS OR MATERIALS

"Seizure" means the overt removal of declared peaceful activities from the exercise of effective authority by the international control agency. The seriousness of seizure of atomic plants and materials would depend on the stage in the production of nuclear fuels at which seizure occurred. The relative dangers of the material at various stages have been considered and are set forth in the earlier findings. The problem of erecting safeguards against the dangers from seizure is before the Commission, but has not yet been given more than preliminary consideration. However, it is possible at this time to indicate the scope of the problem and some of the considerations involved.

The agreed finding of the Scientific and Technical Committee in this connexion, as stated in its report, is: "We have been discussing the possibilities of clandestine diversion of materials from the peaceful activities in the domain of atomic energy, but we must not overlook that with certain systems of control one would have to consider the possibility that plants or materials might be seized. This implies a danger, the seriousness of which would be greatest in the case of seizure of stocks of concentrated nuclear fuel, because from that stage weapons

could be produced most quickly and in relatively small plants. Next in order of seriousness would be the seizure of plants producing nuclear fuels. A wide geographical dispersal of stocks and plants and the restriction of stocks to minimum operating levels would reduce the risk that a large quantity would be involved in a single seizure. Seizure of mines or of facilities at other early stages would only be of advantage to those desiring to make weapons if they had at their disposal a plant capable of producing nuclear fuel.”

Political and general considerations are paramount in the matter of safeguards against seizure. No technical measures are likely to prevent seizure by a nation that has determined upon aggression, and such measures as could be administered by an international control agency could hardly give complete satisfaction from the point of view of safety. There may, however, be some measures of a technical nature which could be applied through an international control agency; these measures would assist in forestalling seizure and would tend to minimize the military advantages that an aggressor could expect from seizure.

The nature of the evidence reviewed by the Commission to date suggests that its further deliberations on the subject of seizure should include consideration of the following topics:

1. Seizure as it applies to materials and plants under different types of safeguards.

2. The desirability of the geographical dispersal of plants and stocks of materials.

3. The possibility of the reduction of inventories of materials in process or in storage.

4. The possibility of making the materials for power unsuitable for weapons.

5. The desirability of providing for the damaging or destruction of plants before they can be seized.

Summary

Problems relating to seizure have been considered thus far only in preliminary terms. The major questions of seizure are political rather than technical. It appears, however, that technical measures could reduce the military advantages and therefore the dangers of seizure.

CHAPER 8.-CO-ORDINATION OF SAFEGUARDS

Introduction

The preceding chapters of this report have discussed the safeguards required at each stage in the production and use of atomic energy to prevent the dangers indicated in the report of the Scientific and Technical Committee. In designing an effective and comprehensive system of control, attention must be given not only to the safeguards required at the several stages, but also to the interrelation among those safeguards. Of particular importance in this connexion is the scheduling of operations at successive stages in such a way that stocks of dangerous material are kept to a minimum.

The co-ordination of safeguards raises further important questions as to the nature, organization and powers of the international control

agency responsible for the control of atomic energy. Preliminary investigations have indicated that, when considering the powers of the international control agency, further attention will have to be given to the interrelation between controls at various plants and the degree of control over uranium and thorium through all of the processes. These subjects have not as yet been considered by the Committee.

FINDING

1. In addition to material accounting at each individual step in atomic energy processes, the international control agency should provide for material accounting checks between points of shipment and receipt of material as a means of detecting possible diversion in transit.

2. The international control agency should control the storage and shipment of uranium and thorium materials to the degree necessary for security purposes.

3. The international control agency should itself store and handle all enriched or pure nuclear fuel in transit. This does not necessarily imply ownership, either of the materials or of the transit or storage facilities, questions which have not yet been discussed.

4. Since stocks of concentrated or pure nuclear fuel are acutely dangerous, operations at successive stages in the production of atomic energy should be so scheduled that stocks of materials in transit and in storage are minimized, but without interfering unduly with the development and effectiveness of peaceful activities.

61. INTERNATIONAL CONTROL OF ATOMIC ENERGY: STATEMENT BY CANADA, CHINA, FRANCE, THE UNITED KINGDOM AND THE UNITED STATES, OCTOBER 25, 1949 1

On 24 October 1949, the representatives of Canada, China, France, the Union of Soviet Socialist Republics, the United Kingdom and the United States of America agreed to send to the Secretary-General of the United Nations, for transmission to the General Assembly, the following interim report on the consultations of the six permanent members of the Atomic Energy Commission:

"In paragraph 3 of General Assembly resolution 191 (III) of 4 November 1948, the representatives of the Sponsoring Powers, who are the Permanent Members of the Atomic Energy Commission, namely, Canada, China, France, the Union of Soviet Socialist Republics, the United Kingdom of Great Britain and Northern Ireland and the United States of America, were requested to hold consultations 'in order to determine if there exist a basis for agreement on the international control of atomic energy to ensure its use only for peaceful purposes, and for the elimination from national armaments of atomic weapons'.

"The first meeting took place on 9 August 1949. The consultations have not yet been concluded and are continuing but, in order to inform the General Assembly of the position which

1 Department of State Bulletin, November 7, 1949, pp. 686-690.