Slayt 1

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Three Mile Island Accident, 1979
Tugrul Züre Murat Kezgin Ahmet Agdaci
2
Summary of Events

• Problem with main feed water system
• Stuck relief valve
• Intense heat caused core meltdown
• Contaminated coolant and gasses

3
Health Effects
a two-headed calf that was stillborn near the
Three Mile Island Plant two years after the
accident.
Mutant rose

• xenon and iodine radioisotopes were released from
  the power plant to the environment at Three Mile
  Island incident.
• TMI-2 accident caused concerns about the
  possibility of health effects by radiation,
  principally cancer.
• "...there were reports of erythema, hair loss,
  vomiting, and pet death near TMI at the time of
  the accident... -Dr. Steven Wings
• Since the accident in 1979, no one found serious
  health effects such as cancers which might be
  linked to the accident.

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Impact of the Accident
Measures After The Accident

• Upgrading and strengthening of plant design and
  equipment requirements.
• Operator trainings are improved.
• Regular analysis of plant performance by senior
  NRC managers to find if a plant needs additional
  regulation.
• Installing additional equipment to lighten
  accident conditions, monitor radiation levels and
  plant status.
• NRC started to arranged international activities
  to share knowledge of nuclear safety with other
  countries

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Current Status

• Closed and defueled
• Coolant system drained, the radioactive water
  decontaminated and evaporated
• TMI site started to be monitored

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Problems in the NRCs Fact Sheet

• The main feed water pumps stopped running,
  caused by either a mechanical or electrical
  failure, which prevented the steam generators
  from removing heat.
• Signals available to the operator failed to show
  that the valve was still open In addition, there
  was no clear signal that the pilot-operated
  relief valve was open.
• They did not know that the core had melted, but
  they immediately took steps to try to gain
  control of the reactor and ensure adequate
  cooling to the core.
• But new concerns arose by the morning of Friday,
  March 30. A significant release of radiation from
  the plants auxiliary building, performed to
  relieve pressure on the primary system and avoid
  curtailing the flow of coolant to the core,
  caused a great deal of confusion and
  consternation.
• The accident was caused by a combination of
  personnel error, design deficiencies, and
  component failures.
• In July 1980, approximately 43,000 curies of
  krypton were vented from the reactor building.

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Conclusion

• Safety problems led the nuclear accident .
• Engineers and operators didnt behave ethically
  and let the radioactive gases vent.
• Also they did mistakes and couldnt prevent the
  accident.
• Clean up expenses were so high.
• Publics confidence to nuclear energy decreased.
• Harms of radioactive gases werent so high.

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Ethical Analysis