TMI-1

Articles: 
Type: 
Articles: 
Type: 

 

Contact: Scott Portzline - Three Mile Island Alert 717-232-8863

Nuclear Watchdog Group Says the Results of a Hostile Action Drill at Three Mile Island are Grievously Misleading

A key element was missed during the hostile action drill at Three Mile Island (TMI). Specifically, emergency responders could be prevented from carrying out their responsibilities if the bridges at TMI are not under the control of the licensee. The control of approach routes was previously an NRC goal during the rule making process in which TMI Alert participated.

Type: 

by Scott Portzline

The new steam generators at Three Mile Island have an unexpected flaw which is yet to be understood by Areva, the twice financially rescued French company (last year by US tax dollars) which built them, or by the engineers in the US nuclear industry. Fortunately, the engineers at TMI correctly determined that abnormal wear was occurring at unexpected locations on 257 steam generator tubes. Their observation caused Arkansas Nuclear to re-evaluate data which it had glossed-over indicating that the same thing was occurring at their reactor site.

These new "enhanced" steam generators were supposed to save money by decreasing maintenance and by increasing the amount of electrical power generated. The Nuclear Regulatory Commission (NRC) was so confident in the new metal alloys used in the steam generators that they would automatically extend inspection cycles to any licensee which requested it. But, now the NRC should mandate that the inspection of these new steam generators be more thorough and occur during each refueling outage. TMI will do this voluntarily.

The problem will probably be blamed on a design flaw which allowed steam tubes to bang against each other. Either the proximity of the tubes to each other, or inadequate stiffness can be blamed for the unexpected wear. The high temperatures of the pressurized water running through (and around) these tubes cause the tubes to expand and to bow sideways.

There are concerns that under abnormal conditions, when the temperatures can double or triple, additional tubes will bow even farther and then additional tubes may be compromised. Add to that the vibrations and shock waves caused by steam voids (which happened at TMI in 1979) and you have a large break loss of coolant accident on your hands as numerous tubes fail.

At the moment, there is still enough safety margin at TMI during normal conditions. Exelon claims that a "large break loss of coolant accident evaluation also demonstrates significant margin" as far as the steam generator tubes are concerned. Their report allows for tripled pressure differentials to support their analysis. However, there is no discussion of the temperature differences which allow the tubes to bow. During the 1979 emergency, temperatures in the reactor rose ten-fold. Steam generator "A" tore its guts apart.

The NRC's Advisory Committee on Reactor Safeguards, which conducted a review in 2001 stated that, "The NRC staff does not currently have a technically defensible analysis of how steam generator tubes, which may be flawed, will behave under severe accident conditions in which the reactor coolant system remains pressurized."

Additionally, there is a special manner in which tube failure can cause what is known at a guillotine rupture accident. If a high temperature jet rushes from a failed tube and cuts through an adjacent tube, the process can repeat itself in a rapidly cascading failure. A report on experiments by the Rockwell International states "[Damage] occurred on the surrounding tubes due to the high temperature reaction."

Knowing this, and despite the chances of its occurrence being very low, the NRC should address this as a Safety Issue. A spokesman for TMI stated that the newly found flaws are not considered a safety issue.

The problem reminds me of a fatal flaw that existed during the Apollo Moon Program. The original Saturn rockets had a vibration problem called "pogo." Liquid fuel slammed against the bottom of the fuel tank and then slammed against the top. The forces threatened to tear apart the rocket. Designers solved the problem by installing baffles to prevent the sloshing of the fuel.

Now back to nuclear thinking: For years the industry compared itself to "rocket science" and that ordinary citizens were unable to understand the complexities involved. Therefore citizens who worried about nuclear safety were viewed as ignorant, over-emotional pests. As the years went on and citizens became very sophisticated with their knowledge and familiarity of the regulatory process, citizens were accused of wanting to over-regulate the industry. New cries went up from the industry and even from the NRC's chairman Nils Diaz, "This is not rocket science."

The steam generator concerns are on the level of rocket science. These are new materials, higher pressures and temperatures may be involved, and new operational conditions and data; just like rocket science. No one should forget that experiments are still being thrust on the public in this nuclear realm.

 

Type: 

 

The new steam generators at Three Mile Island have an unexpected flaw which is yet to be understood by Areva, the twice financially rescued French company (last year by US tax dollars) which built them, or by the engineers in the US nuclear industry. Fortunately, the engineers at TMI correctly determined that abnormal wear was occurring at unexpected locations on 257 steam generator tubes. Their observation caused Arkansas Nuclear to re-evaluate data which it had glossed-over indicating that the same thing was occurring at their reactor site.

These new "enhanced" steam generators were supposed to save money by decreasing maintenance and by increasing the amount of electrical power generated. The Nuclear Regulatory Commission (NRC) was so confident in the new metal alloys used in the steam generators that they would automatically extend inspection cycles to any licensee which requested it. But, now the NRC should mandate that the inspection of these new steam generators be more thorough and occur during each refueling outage. TMI will do this voluntarily.

The problem will probably be blamed on a design flaw which allowed steam tubes to bang against each other. Either the proximity of the tubes to each other, or inadequate stiffness can be blamed for the unexpected wear. The high temperatures of the pressurized water running through (and around) these tubes cause the tubes to expand and to bow sideways.

There are concerns that under abnormal conditions, when the temperatures can double or triple, additional tubes will bow even farther and then additional tubes may be compromised. Add to that the vibrations and shock waves caused by steam voids (which happened at TMI in 1979) and you have a large break loss of coolant accident on your hands as numerous tubes fail.

At the moment, there is still enough safety margin at TMI during normal conditions. Exelon claims that a "large break loss of coolant accident evaluation also demonstrates significant margin" as far as the steam generator tubes are concerned. Their report allows for tripled pressure differentials to support their analysis. However, there is no discussion of the temperature differences which allow the tubes to bow. During the 1979 emergency, temperatures in the reactor rose ten-fold. Steam generator "A" tore its guts apart.

The NRC's Advisory Committee on Reactor Safeguards, which conducted a review in 2001 stated that, "The NRC staff does not currently have a technically defensible analysis of how steam generator tubes, which may be flawed, will behave under severe accident conditions in which the reactor coolant system remains pressurized."

Additionally, there is a special manner in which tube failure can cause what is known at a guillotine rupture accident. If a high temperature jet rushes from a failed tube and cuts through an adjacent tube, the process can repeat itself in a rapidly cascading failure. A report on experiments by the Rockwell International states "[Damage] occurred on the surrounding tubes due to the high temperature reaction."

Knowing this, and despite the chances of its occurrence being very low, the NRC should address this as a Safety Issue. A spokesman for TMI stated that the newly found flaws are not considered a safety issue.

The problem reminds me of a fatal flaw that existed during the Apollo Moon Program. The original Saturn rockets had a vibration problem called "pogo." Liquid fuel slammed against the bottom of the fuel tank and then slammed against the top. The forces threatened to tear apart the rocket. Designers solved the problem by installing baffles to prevent the sloshing of the fuel.

Now back to nuclear thinking: For years the industry compared itself to "rocket science" and that ordinary citizens were unable to understand the complexities involved. Therefore citizens who worried about nuclear safety were viewed as ignorant, over-emotional pests. As the years went on and citizens became very sophisticated with their knowledge and familiarity of the regulatory process, citizens were accused of wanting to over-regulate the industry. New cries went up from the industry and even from the NRC's chairman Nils Diaz, "This is not rocket science."

The steam generator concerns are on the level of rocket science. These are new materials, higher pressures and temperatures may be involved, and new operational conditions and data; just like rocket science. No one should forget that experiments are still being thrust on the public in this nuclear realm.

The Hubble Telescope problem was another example of rocket science gone awry. One very small miscalculation made the telescope useless until a multi-million dollar fix could be installed. Similarly, a dreadful oversight by the nuclear industry has severely damaged the reactor containment buildings at reactor sites in Ohio and Florida. The problem was caused when holes were being cut into the reactor containment buildings to replace worn out steam generators or other reactor components. The circular concrete buildings have metal tendons which are tensioned to add strength to the concrete. But, engineers cut through these tendons and the concrete cracked apart! Then they had the audacity to say that the damage could not be predicted! The projected cost for repairs at the Florida Crystal River plant was $2.5 billion dollars. A few months ago new cracks were found and the plant may be totally useless now.

Scott Portzline TMI Alert

 

Type: 

 

Three Mile Island

July 20 – The NRC granted requests from TMI operator Exelon for relief and allowed it to use alternative procedures to certain requirements for in-service examination of components and steam pressure tests conducted during 10-year intervals. The requests were part of the fourth 10-year inspection that began on April 20, 2011 and ends no later than April 19, 2022.

Type: 

2001-2011

  • From October 5-9, 2001, “Licensee sirens in Lancaster County were inoperable October 5 through October 9, 2001, due to a radio transmitter being deenergized at the county facility. The transmitter is part of the siren actuation system. This issue is unresolved pending further investigation into the lines of ownership and maintenance of the actuation system.” (IR 50-289/01-07).
  • On January 11, 2002 , Siren testing at TMI encountered numerous problems: all sirens failed in York County and one siren failed in Lancaster County. AmerGen attributed to computer malfunctions.
  • On March 3, 2002, a siren malfunctioned in York County again. During TMI’s annual test on on January 30, 2002, all 34 sirens in York County, located within ten-miles of the plant, failed to activate.
  • On June 25, 2002, “...station emergency preparedness personnel discovered that the emergency planning siren base station at the site, was unable to communicate with the off site sirens, due to external radio frequency noise in the area.” (IR-50-277/02-05; 50-278/02- 05)
  • On December 12, 2002, TMI sirens malfunctioned in Cumberland and York counties. In Dauphin County, 28 sirens malfunctioned due to the “inadvertent” discharge of the “space bar” by a computer operator (Refer to June 22, August 15 and October 5-9, 2001 and January 11, March 3 2002, for related problems.)
  • On July 28, 2010, the NRC issued a report of an inspection at the Three Mile Island plant for the quarterly period ending June 30.
    The NRC said it found no findings of significance. However, it noted that the TMI plant operator identified a violation that was determined to be of very low safety significance. The NRC said it would treat the violation as a non-cited violation.
    The issued stemmed from the TMI Emergency Plan and the plant paging system. The report said that plant operator Exelon began testing its on-site speakers in March 2010. A total of 301 out of 405 speakers were tested, and of those tested, 108 had identified deficiencies, the report said. “Contrary to the TMI Emergency Plan, the 108 speakers would not provide immediate warning and instruction to on-site personnel during an emergency,” the report said. “Upon discovery, Exelon issued a standing order to issue blow horns to operations and security staff to notify people in areas that would need to be evacuated during an emergency.“ The report added, “The finding is of very low safety significance because prompt compensatory measures were taken upon discovery.”
  • June 23, 2011, Three Mile Island's emergency sirens sounded at 12:15 p.m. Thursday as part of an annual test -- but it didn't work everywhere. The 96 sirens, which cover five counties and are within a 10- mile radius of TMI, were set to sound for three minutes. They sounded everywhere except in Lancaster County.
    Officials ran another test, this time just in Lancaster County, at 1:15 p.m. At that time, the sirens did work in Lancaster County. (WGAL)
    A Lancaster County EMA official said Lancaster County and another county pressed the siren test button simultaneously and the system did not register the Lancaster County test.
  • July 14, 2011, A Three Mile Island warning siren sounded accidentally on Thursday afternoon, according to Dauphin County officials.
    The TMI siren at 2nd and Hanover streets in Hummelstown inadvertently sounded at 1:19 p.m. It lasted for fewer than 30 seconds, according to Stephen Libhart, Director of the Dauphin County EMA.
    Libhart says Exelon will repair or replace any components of the siren if necessary. (WGAL)

 

Type: 

 To read the NRC memo related to the TMI operators license exam, open pdf: 

 

Articles: 
Type: 

The following is the full content of a report that an "event" at

the Three Mile Island nuclear power plant's Unit 1 reactor had been retracted.

In this case, the "event" refers to three safety relief valves not opening as

they were set to do. "Retraction" does not mean the situation described did not

occur, it means that it will no longer be categorized as an "event."

 

!!!!! THIS EVENT HAS BEEN RETRACTED. THIS EVENT HAS BEEN RETRACTED !!!!!

 

Power Reactor Event Number: 45464

Facility: THREE MILE ISLAND

Articles: 
Type: 

Pages