The isolation of construction workers and facility personnel to prevent potential recruitment by foreign spies was another critical security task. The construction force was particularly difficult to control. At least 15 of 114 GULAG camps supported the construction of nuclear facilities. In late 1947, over 20,000 prisoners were working in Ozersk, and about 10,000 were in Sarov. There were over 18,000 prisoners in Novouralsk during 1950-51. Over 27,000 were in Zheleznogorsk in 1953.
The Soviet government adopted several measures to minimize the security risk posed by the prison labor force. The KGB's policy was not to send prisoners with sentence terms of less than five years or those with sentences expiring in less than three years to nuclear sites. After completing nuclear construction projects, the prisoners finished their terms at the Vorkuta camps in Siberia, which were famous for their remoteness and harsh conditions. When released from the camps, the prisoners were sent to far away regions in the north and to Central Asia. Only in 1955, after several cooling-off years, were some of them allowed to return to central Russia. According to a journalist's account: "[T]he news spread quickly throughout all GULAG camps that [a nuclear construction assignment] was effectively the same as a death sentence."
Soldiers comprised the other large segment of the nuclear construction force. Once they completed their service, they all had to sign a 25-year non-disclosure agreement. The KGB, the agency in charge of construction, was directed to retain discharged soldiers and to hire them as civilians to work on other special projects.
German and Austrian scientists and engineers, who became involved in the Soviet nuclear program after World War II, presented the Soviet security apparatus with a particularly delicate problem. The program needed their expertise. Yet, it was clear that most of them eventually would go home and become accessible to Western intelligence organizations. Moscow decided to concentrate them to the extent possible at NKVD-run facilities (such as the Sukhumi laboratory on the Black Sea); to exclude German scientists from work that was directly related to nuclear weapons R&D and production; and to institute a two-year cooling-off period prior to repatriation. Even so, German scientists gave the West much of the initial data on the facilities, personalities, and technical directions of the Soviet project.
Tens of thousands of workers and engineers were required to operate the newly built facilities. Personnel selection was under the control of the Communist Party's Central Committee, the Council of Ministers, and regional party organizations. There was a process of double selection of personnel based on recommendations by those already working in the program and background investigations by the KGB and its predecessor organizations.
Closed cities made the job of insulating and controlling nuclear workers relatively straightforward. Upon arrival, new residents received instruction in security procedures and signed a nondisclosure agreement, which, among other things, prohibited them from disclosing information about the city and the nuclear facility; the names of nearby towns, rivers, lakes, and other landmarks; the transportation routes to the area; and other information that could help in locating the city. New workers were also encouraged to limit correspondence and social contacts with people outside the closed cities. Personal phone contacts with the outside world were prohibited. All correspondence was censored. Generally, people lived and worked behind barbed wire, all aspects of their lives penetrated and controlled by the security services. According to Yuli Khariton, a famous warhead designer from Sarov, "Beria's people were everywhere."
Initially, closed-city residents could leave their areas only for business. On rare occasions, they could go to sanatoriums for medical treatment or leave for family emergencies. Every such trip had to be approved by the security director, and its duration was checked by security officers.
In the 1950s, these security rules were somewhat relaxed. By 1954, facility directors, in coordination with the KGB, could grant permission to selected workers to leave their cities for vacations, medical treatment, or study. Nonetheless, workers willing to spend their vacations inside a city received bonuses amounting to 50 percent of their monthly salaries. All travelers still had to have their travel routes approved and sign nondisclosure agreements. Blanket permission to leave the cities was not issued until 1957, when all residents were issued passes permitting them to leave for one day any time they wanted. By that time, the Soviet Union already possessed a credible nuclear deterrent (including nuclear-armed medium-range ballistic missiles) against the West.
Keeping Technology Secret
Secrecy was a hallmark of Soviet nuclear science and technology. As late as the 1980s:
[C]lassification stamps Secret and Top Secret concealed everything even remotely connected with our activities and achievements in high technologies . . . . The stamp For Official Use (DSP) was on every piece of conceivably interesting science and technology information. Only after the Chernobyl disaster . . . was the censorship system forced into permitting publications in the open literature about the real state of the nation's atomic industry.
Even within this generally secretive environment, the nuclear weapons program existed inside a cocoon of secrecy of its own. Nuclear materials and operations had codenames, which were different at different facilities and which were changed periodically. In the late 1940s and early 1950s, for example, natural uranium was assigned such names as strontium, lead, tar, phosphorus, bismuth, titanium, kremnil, A-9, Azh-9, BR-10, and P-9, while HEU had the codenames of kremnil-1 and moist kremnil.
Compartmentalization of information and operations was near absolute. Mikhail Gladyshev, former chief of the plutonium purification shop at the Mayak complex in Ozersk, has remarked:
[A]ctivities of the "regime services," headed by Beria, were very stern and bordered on insanity . . . . Often, there was a threat to the safety of workers . . . . As you see, our work had double risks—losing health and losing freedom. This was the difficult fate of those who made the atomic bomb.
Information about production outputs was particularly sensitive. According to Gladyshev:
[W]e put the [plutonium] paste in a box and transferred it to the consumer plant. How much plutonium was in that box we didn't know and it was not recommended for us to know. Even later, when I was the plant's chief engineer, the plans for plutonium production were known only to the facility's director, and all documents were prepared in single copies.
Supported in large part by the fear of punishment—an important consideration, given Stalinist repressions and campaigns to unmask spies and saboteurs—the regime of secrecy was further cemented by genuine patriotism and the sense of purpose among nuclear workers.