TMIA's Statement; Re: NRC issues inspection report on TMI-1 "contamination event"

NRC issues inspection report on TMI-1 "contamination event"
“The contamination of 145 workers is significant and was avoidable.
This challenge to public health and safety was caused and aggravated
by poor housekeeping, inattention to detail, and delayed response
times.”

Eric Epstein, Chairman of TMI-Alert

Nuclear Regulatory Commission (NRC) has issued its
inspection report on the worker contamination event at the Three
Mile Island 1 nuclear power plant on Nov. 21, 2009.

A copy is attached.

The NRC has identified three "green" (very low safety significance)
inspection findings after reviewing Exelon's handling of the event,
which occurred during a refueling and maintenance outage at the
plant. They are:

* Exelon did not use process or other engineering controls, to the
extent practicable, to control the concentration of radioactive materials
in the air during the vacuuming of reactor coolant system piping.
Specifically, the vacuum used was not equipped with a
high-efficiency particulate air (HEPA) filter and allowed the dispersal
of airborne radioactive particulate contamination inside the plant's
containment building, the massive steel-reinforced concrete structure
which surrounds the reactor. This led to the alarming of airborne
radioactivity monitors and prompted the evacuation of about 175
workers from the building. The radioactivity event resulted in 145
workers sustaining external and/or internal contamination, though
none sustained any radiation dose approaching regulatory limits.
Only one worker sustained an internal exposure that met internal
company recording requirements.

* From Nov. 12 to 21, 2009, Exelon did not effectively manage Three
Mile Island 1 containment openings and ventilation system flows in
order to maintain inward airflow and promptly detect and minimize
the release of radioactivity from an opening cut in the containment
building to allow for the replacement of the plant's steam generators.
As a result, an uncontrolled airborne radioactivity release occurred
from the construction opening on Nov. 21, 2009 at about 3:45 p.m.
Airborne radioactivity was also released from the opening liner on
Nov. 12 through the time of the uncontrolled release. The releases
were determined to be low-level and not pose a threat to worker or
public health and safety. The projected dose at the site boundary
was less than quarterly and annual Public Dose As Low As
Reasonably Achievable (ALARA) limits.

* Exelon did not implement timely follow-up and corrective action to
minimize radioactivity released to the environment as required by plant
radiation protection procedures. Specifically, upon discovery on
Nov. 16 of an unplanned, unfiltered radioactive release pathway
from the containment building construction opening to the environment,
plant personnel did not promptly initiate a Condition Report or assign
appropriate significance to the issue. Consequently, an unfiltered
release pathway from the containment building existed until appropriate
controls were reestablished on Nov. 21.

Because the inspection findings are "green," Exelon will have an
opportunity to place them in the Three Mile Island 1 corrective action
programs and take steps to prevent a recurrence. The NRC will follow
up on these actions through our normal inspection process to ensure
the actions have been carried and are effective.