Atomic Energy Regulatory Board, India 1 Regulator’s role in enhancing transparency in informing the public – The Mayapuri Accident R. Bhattacharya Secretary, Atomic Energy Regulatory Board (AERB) Director, Industrial Plants Safety Division, AERB & Director, Information & Technical Services Division, AERB Mumbai, India email: [email protected]International Experts’ Meeting on Enhancing Transparency and Communication Effectiveness in the event of a Nuclear or Radiological Emergency 18-20 June, 2012 Vienna, Austria 1
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Atomic Energy Regulatory Board, India1
Regulator’s role in enhancing transparency in informing
the public – The Mayapuri Accident
R. BhattacharyaSecretary, Atomic Energy Regulatory Board (AERB)
Director, Industrial Plants Safety Division, AERB
&
Director, Information & Technical Services Division, AERB
Coordinate Actions Through :• District authorities• NDRF• SDRF / DDRF• Other Resources
After Information DC/DM (DDMA) to take Full Charge of the situation
7
Atomic Energy Regulatory Board, India8
The Mayapuri Accident
8
Scrap market, Mayapuri
Atomic Energy Regulatory Board, India9
Action on 1st information: April 7-9, 2010 (Initial Phase)
� April 7, 2010 (afternoon) message received at AERB from a
Hospital at Delhi – An owner (32 yrs) of a junk shop suspected of
injuries from exposure to radiation (along with medical report)
� April 7, 2010 (evening) two officers from AERB monitored the
area in & around the junk shop and found high levels of radiation
(~20 mGy/h). They segregated contaminated junk, shielded with
available steel plates & cordoned off the area.
� Crisis Management Group (CMG) of Department of Atomic Energy was activated
Atomic Energy Regulatory Board, India10
� April 8, 2010, CMG convened a meeting. Planning & Coordination
for source recovery operation was finalized. A team of officers of
AERB, other DAE units, National Disaster Response Force (NDRF)
and police was formed.
� In the night hours of April 9, 2010 the team could identify the
source (Cobalt-60), locate and recover all sources present in the
shop (about 90 % of total inventory)
� The recovered sources were transferred into shielding flask and
sent to Narora Atomic Power Station (NAPS), nearest DAE unit for
safe & secure storage and further investigation.
Atomic Energy Regulatory Board, India11
Action on 2nd information: April 13-14, 2010
� On April 13, 2010 at about 16:00 hrs a surveillance check by DelhiEmergency Response Centre (ERC) revealed elevated radiation level ata nearby closed junk shop.
� In the night hours of April 14, 2010 the team could identify, locate andrecover two pencils and a multiple source cage with capacity toaccommodate 48 pencils (about 10 % of total inventory). Recoveredsources were transferred to NAPS in a shielding flask.
� The team also carried out radiation survey of about 800 shops. General
radiation level observed was near background (80 – 180 nGy/h). The
owner of the shop and his coworkers did not show any sign of radiation
injury.
Atomic Energy Regulatory Board, India12
Action on 3rd information April 16-17, 2010
� On April 16, 2010 information was received that a person has been
admitted to a hospital of Delhi with localized radiation injury.
� The team recovered the source from the wallet of the injured person
and transferred to shielding flask and transported to NAPS, Narora
Infrastructure
� Delhi Police Force
� Emergency Response Centres (ERCs)
� National Disaster Response Force (NDRF)
� Experts from units of Department of Atomic Energy (DAE)
Atomic Energy Regulatory Board, India13
• A team of medical officers from Department of Atomic Energy
(DAE) provided guidance to the local hospitals in treatment of the
injured persons.
• Out of seven, one succumbed to the radiation injuries. Other six
persons have been discharged from the hospitals on various dates,
last one being on May 24, 2010.
• In a campaign to screen the individuals (for medical management)
suspected to have received high doses, bio-dosimetry (CA test) of
more than 40 blood samples of the persons having even a remote
connection with the incident was carried out. None of them have
shown any significant exposure to radiation.
Atomic Energy Regulatory Board, India14
Estimated dose due to single exposure and INES
reporting
14
Worker Dose (Gy)
Worker 1 3.7
Worker 2 0.6
Worker 3 0.4
Worker 4 1.6
Worker 5 1.8
Worker 6 1.2
Worker 7 1.3
Event Reported as INES Level-4
Atomic Energy Regulatory Board, India15
� 1969: Professor of Chemistry Dept, Delhi University imported Gamma
Cell-220 research irradiator (containing Co-60) from Atomic Energy of
Canada Limited, Canada. Authorisation issued by DRP, BARC
� 1985: Professor retired. The gamma cell, thereafter remained unused.
� February 2010: Delhi university auctioned the gamma cell to a scrap
dealer (based on decision made by a committee of professors) and
purchased by a junk material dealer of Mayapuri, Delhi.
� April, 2010: This Gamma Cell was dismantled by local workers, none of
these workers showed any symptoms of radiation effects. Worker ‘5’, who
died on April 29, 2010 of radiation injuries, had worked on the SS part
(cage with pencils) after getting it from the dealer who had dismantled it.
15
What had happened?????
Atomic Energy Regulatory Board, India16
More about the ill-fated gamma cell...
� Self contained dry source storage irradiator with a cylinder source
cage which can hold 48 pencils.
� Housed 16 pencils shielded by 3 tons of Pb
� Each pencil had 7 slugs and 2 dummy spacers.
� Total activity content of the cell: 3978 Ci
(as of Aug, 1969)
� Activity content in pencil: 276Ci
� Activity content in slug: 20-87 Ci
� Authorisation issued by DRP in 1970. Undertaking by Delhi University:
“radiation sources of gamma cell will not be sold, rented or
transferred to any other institution”.
Since Gamma cell is considered as inherently safe equipment, it was not
subjected to periodic regulatory inspection as is done for other sources.
16
Atomic Energy Regulatory Board, India17
April 16
• A team of AERB & Board of Radiation & Isotope Technology (BRIT) officers
conducted the inspection.
• Team could identify a 48 slot cage of a self contained dry storage irradiator
(gamma cell) and its pencils
• The gamma cell was not manufactured in India
• Low activity level found in source pencils indicated that they might have been
manufactured 30-40 years ago
May 3&4
• A team of AERB & BRIT officers conducted further inspection.
• All the sources of the gamma cell (112 slugs from 16 pencils) were identified &
accounted for.
Inspection of recovered sources at
Narora Atomic Power Station (NAPS)
Atomic Energy Regulatory Board, India18
Projected assessment of radiation dose
Radiological status due to presence of contamination mainly
in soil on the road in front of the shop and neighbouring
shops, from where Co-60 sources were recovered:
� Before removing the contaminated soil and
concretisation: < 10 mSv/a
� After decontamination and concretization: < 1mSv/a