Period+9+-+TMI

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On March 29, 1979, the infamous crisis began when the main feedwater pumps stopped running. This caused the turbine and reactors to shut down. The pressure in the nuclear section of the plant began increasing. The emergency feedwater pumps were triggered and as the pressure began to decrease empty pockets with no water began to form. This caused the readings on the pressurizer were then inaccurate causing the operator to shut the machine off before it was cooled completely. The nuclear fuel began to overheat damaging the reactor. A "meltdown" techinically did not occur because all the melted fuel remaind contained. However, the radioactivity in the reactor coolant increased a lot causing the worldwide commotion. The TMI-2 reactor still remains shut, and the TMI-1 license expires in 2014 at which time it will be shut down.

Residents living in the area at that time were in little danger of exposure to radioactivity. Each person of the 2 million residents only received 1 milirem of radioactivity. Exposure from a chest x-ray is 6 milirems. Although questions were raised after the event, no claim could be related to the event even after multiple studies of the soil, water, air, and vegetation.



Since the TMI accident many policies have been changed. >  >    >    >    >    >    >    >
 *  The plant has been upgraded and strengthed equipment way. It has also been protected about fires and has resolved piping issues. The plant can also automatically shut down.   
 *  Improved instruction to avoid the confusing signals that plagued operations during the accident;
 *  Enhancement of emergency preparedness to include immediate NRC notification requirements for plant events and an NRC operations center which is now staffed 24 hours a day. Drills and response plans are now tested by licensees several times a year, and state and local agencies participate in drills with the Federal Emergency Management Agency and NRC;
 *  Establishment of a program to integrate NRC observations, findings, and conclusions about licensee performance and management effectiveness into a periodic, public report;
 *  Regular analysis of plant performance by senior NRC managers who identify those plants needing additional regulatory attention;
 *  Expansion of NRC's resident inspector program -- first authorized in 1977 -- whereby at least two inspectors live nearby and work exclusively at each plant in the U.S to provide daily surveillance of licensee adherence to NRC regulations;
 *  Expansion of performance-oriented as well as safety-oriented inspections, and the use of risk assessment to identify vulnerabilities of any plant to severe accidents;
 *  Employment of major initiatives by licensees in early identification of important safety-related problems, and in collecting and assessing relevant data so lessons of experience can be shared and quickly acted upon;
 *  Expansion of NRC's international activities to share enhanced knowledge of nuclear safety with other countries in a number of important technical areas.

Bibliography: Images
 * http://www.nrc.gov/reading-rm/doc-collections/fact-sheets/3mile-isle.html
 * http://www.policyalmanac.org/environment/archive/three_mile_island.shtml
 * http://www.opsi.gov.uk/si/si2002/02267701.gif
 * http://www.ohiocitizen.org/campaigns/electric/2004/ph_three_mile_island500.jpg
 * http://www.yorktownsquare.com/photos/three%20mile%20island.jpg
 * http://www.solcomhouse.com/images/testk.jpg
 * http://upload.wikimedia.org/wikipedia/commons/2/2e/Three_Mile_Island_nuclear_power_plant.jpg
 * http://www.world-nuclear.org/assets/0/16/660/676/41e5fd37-ce9c-4471-a3c0-489c930ed067.jpg
 * http://www.pollutionissues.com/images/paz_01_img0068.jpg


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