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Greenpeace Vladivostok Report 

 6 November 1991 



undergoing refuelling at the submarine repair and refuelling facility on Chazma Bay. The Navy 

 ofBcers Greenpeace spoke with said the explosion resulted after the reactivity control elements of 

 a new reactor core were inadvertently removed as the reactor lid was being re-lifted, after being 

 improperly placed the first time. 



The explosion ejected highly radioactive materials onto the surrounding land and into the 

 water. According to the Navy officers, several 100,000 curies of radioactivity were released 

 (including the short-lived isotopes). Ten men in the reactor compartment were killed instantly. 

 The submarine has not been repaired and is still visible at dockside at the Chazma facility. 



The 'fallout' from the accident spread across the peninsula (some 6 kms long) towards 

 Vladivostok in a band several hundreds meters wide, but according to the Navy officers, didn't 

 reach the city. A secret Navy map prepared four days after the accident (14 August 1985, 1600 

 hours) outlined an area 3,800 m long and 530 m wide where at the outer edges the level of 

 activity was 600 decays/minute/cm2. . On a local road going through the trace, levels of 4,500 

 decays/minute/cm2 beta radiation were measured (after decontamination in the first four days, this 

 dropped to 20 decays/minute/cm2). Lab analysis showed rates of 1-80 decays/minuteAnn2 for 

 alpha radiation. 



The Navy officers said near the explosion, rates of 260 roentgens/hour were recorded from 

 some smaller pieces of the reactor core. Also some of the radioactive cloud went over 

 Ussuryiskyi Bay to the west, although it did not go as far as Vladivostok. 



Due to the new core there was a relative minimum of accumulated fission products. Thus 

 the Navy officers claim there was little or no plutonium contamination. Also, the officers said the 

 core was only enriched to 20 percent HEU, and so this minimi/ffd uranium-235 contamination. 

 Fmally, the officers said it was the third time for the reactor to be refuelled. They said this 

 accounts for the pervasiveness of cobalt-60 as the remaining source of radiation today. 



A. Qean-up 



In terms of clean-up, for the highly radioactive materials, the Navy officers said a special 

 military service with special equipment for clean-up was used. All the fuel elements which were 

 thrown out, and other highly radioactive materials, were gathered by this special military service 

 and put into specialized containers. The screen assembly which holds the fuel was taken out and 

 a specialized container was created for it These highly radioactive materials were transported by 

 sea to a permanent burial site at Installation 927-IIL 



The screen assembly and the clean-up of the radioactive materials was effected within 10 

 days of the accident, according to the Navy officers. The total volume of the screen assembly and 

 the fuel which was disposed of was approximately 4 m3. The Navy officers said they are not sure 

 about the total volumes of the high and medium level wastes since measurements were not taken 

 in the first few days due to the hurry to eliminate the worst of the problem. 



