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outage than during the plant normal
operation. How Exelon reduces this
vulnerability?
In order to manage site shutdown
safety during a refueling outage, all
Exelon sites use a computer program
titled, PARAGON. The function of
PARAGON is to determine overall
site shutdown safety risk using a tiered
approach. PARAGON is a software tool
that is used to assess the Risk Levels
associated with plant configurations and
outage activities during both the planning
and execution phases of the outage. The
software uses imported information from
the outage schedule or manual user input
to determine the safety status. Specific
schedule activities or hammocks are
scheduled by the Outage Schedulers to
show when systems will be unavailable
for operation and therefore, not counted
on for defense-in-depth. . PARAGON
is designed to take a download from the
scheduling software and look for these
system hammocks and determine which
systems are available or not available
to maintain site shutdown safety.
PARAGON is run and the shutdown risk
profile is validated by not only the Outage
Scheduler, but by Operation’s supervision
prior to release of work. Values for systems
important to shutdown safety, along with
amount of decay heat and time to boil
are inputs to PARAGON. A risk profile
for key safety functions (electrical power,
decay heat removal, etc.) is generated and
an overall site risk color is assigned.
The status of the overall station risk
is communicated to all site work groups,
OCCs and outside contractors on a shiftly
basis. Any changes to the outage schedule
and emergent equipment issues are run
through PARAGON first by Operations
to validate the plant shutdown safety risk
profile has not degraded. Once confirmed,
then work is allowed and schedules are
updated to maintain the overall station
shutdown safety profile.
3. What is Exelon’s Corporate and
Plant Management strategy to direct the
collection and interpretation of outage
experience into the plant improvement
plan after the refueling outage?
Exelon has utilized an effective
tiered approach to capture lessons learned
during a refueling outage. These learnings
are captured in the site’s corrective action
process and utilized as follows:
• During a refueling outage, many of the
site’s lessons learned are documented
live time in the site’s corrective action
process. This is highly encouraged,
since documenting the issue when it
arises provides the best information
and allows for taking proper action
after the outage. Also, sites perform
formal post outage critiques with all
of the site work groups, OCCs and
contractor work groups. Strengths
that need to continue and lessons
learned are captured and documented
in the corrective action process. The
Outage Management organization
will review all of these lessons
learned and make sure actions are
assigned to address resolution before
the next outage. Actions taken
can include updates to the outage
schedule, procedure revisions and
creation of site High Impact Teams
(HIT) to address complex issues.
These actions are tracked, reviewed
(Continued on page 28)
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