1. Ivan P. Salati de Almeida Director of Radiation Protection and Nuclear Safety Brazilian Nuclear Energy National Commission- CNEN September 2012 Small Scale Post-Accident Remediation Senior’s Regulator Meeting Session II - Specific Challenges in Implementing Remediation

2. Brasilia Goiania The accident of Goiania - Brazil R.Janeiro S.Paulo Goiania-Brasilia=173 km Goiania-S.Paulo=937 km Goiania-R.Janeiro=810 km Distances

3. Location City: Goiania (Capital of the State of Goias) Population: ~1.000.000 inhabitants (at the time of the accident) Teletherapy equipment with Cs-137 source Day of the accident: September 13 th,1987

4. Impacted area

5. CS-137 source characteristics Source activity (Sept/87): 1375 Ci (50.9 TBq) Chemical composition: caesium chloride (CsCl) Physical condition: compacted powder Mass CsCl: 93 g Mass Cs-137: 19.3 g

6. Chronology September 10 th to 13 th,1987: part of a teletherapy equipment with a caesium-137 source was removed from an abandoned building and opened, breaching the caesium capsule. September 13 th to 28 th : the Cs-137 was distributed to other people and was spread through other places in the city. Several people were hospitalized with symptoms of high doses irradiation. September 28 th to 29 th : the accident was confirmed by a medical physicist and first actions were taken by local authorities. September 29 th to 30 th : CNEN was notified and sent experts to Goiania.

7. Main issues to be dealt with in the accident People monitoring and assessment of environmental contamination Medical care for victims (irradiated and contaminated) Re-establishment of the source control Decontamination of the places Interim storage for the waste generated Definition and construction of a repository

8. Monitoring people Olympic Stadium (112,800 persons monitored)

9. Data from the accident l Monitored persons = 112,800 l Contaminated persons =271 clothes and shoes = 120 body contamination= 151 l People with deterministic hazards=28 l Victims hospitalized=20 l Syndrome of acute radiation =8 l Hazards in bone marrow =4 l Deaths = 4

10. Main contamination foci

11. Data from the accident l 7 main contaminated places l 42 additional contaminated places l 85 contaminated houses; 7 demolished l 50 vehicles decontaminated l Aerial survey with helicopter equipped with radiation detector (67 km 2 monitored) l Terrestrial survey with a car equipped with radiation detector

12. Data from the accident l Equipment: 55 dose rate meters, 23 contamination monitors 450 dosimetric pens l Professionals involved: 250 technical staff 300 support staff l Time First period: September 29 th to December 24 th 1987 Second period: January to end of March 1988

13. The main piece of the source 0.4 Sv/h at 1m (~120 Ci) Emergency shielding

14. Site isolated for decontamination Decontamination work

15. n 57th Street n Place where the source was opened Decontamination work

16. n House and land contaminated n Dose rate 1,1 Gy/h at 1m Decontamination work

19. equipment head Decontamination work

20. n Assignment of contaminated areas n Criteria (0.5  Sv/h) Decontamination work

21. –5 mSv first year –1 mSv/y dose for the whole life –Critical path for exposition: Gama exposition inside home Gama exposition outside home Internal dose due to inalation and ingestion of fruits, vegetables, domestic animals Criteria for decontamination

22. Remediation actions Part of the soil was removed and covered with concrete Part of the soil was removed and substituted with non contaminated soil Contaminated trees were cut down

23. Waste resulted from the accident 3,500 m 3 (6,000 Ton.) 1,343 metallic boxes 4,223 drums (200 liter each) 10 maritime containers 8 Concrete cylinders VBA type

24. Interim storage of waste

27. Final Repository

28. Deposit 1 (common waste < 90 years) Store about 40% of waste (very low activity). Deposit 2 ( 300 years) Dimensions: –Wall thickness: 25 cm –Basis surface distance from the soil level: 80 cm –Length: 54 m –Width: 14 m –Height: 4 m Final Repository

35. n Regional Center for Nuclear Sciences Information Building Final Repository

36. The end Thank you