Regulatory oversight of nuclear safety in Finland. Annual ... - STUK

4.1 Loviisa NPP
I&C upgrade (LARA) at the Loviisa plant was
postponed until 2014 for Loviisa 1 and until 2016
for Loviisa 2. The systems to be upgraded in the
second phase include the reactor plant I&C systems
most important to safety as well as the I&C
systems of the main safety functions, such as that
of emergency power supply. Postponement of the
I&C upgrade requires the licensee to take action
in order to ensure the sufficiency of maintenance
operations on the existing I&C systems and equipment
as well as the availability of spare parts.
In the main, Fortum Power and Heat Oy and its
Loviisa power plant organisation have operated in a
systematic and development-oriented way to ensure
the safety of the plant. The observations made by
STUK in the course of its oversight indicate that
the organisation produces an abundance of information
regarding its operations, but this information
is not fully utilised for developing the management
system and for improving operations. The work for
improving the operational processes of the organisation
must be continued in order to ensure the safe
operation of the plant, particularly with regard to
developing the management system, ensuring the
quality of procurement operations and developing
the safety culture assessment methods. The
programme for developing project management at
the Loviisa power plant has been successfully completed,
but there is further scope for improvement
in the quality management of project activities.
STUK paid attention to the procedures in the power
company’s assessment and development activities
and in the associated allocation of resources. STUK
required the Loviisa power plant to ensure that the
procedures are appropriate and comply with the
requirements. STUK will assess the situation in
the course of its oversight in 2012. STUK has found
scope for improvement in the follow-up procedures
of the Loviisa power plant regarding the implementation
and success of corrective actions decided following
plant’s own operational events.
STUK-B 147
Table 1. Events at the Loviisa plant units subject to special reports or a root cause analysis and/or classified INES
Level 1 or higher. All events subject to reporting are discussed in Appendix 1 (indicator A.II.1).
Event Non-compliances
with the OLC
Special report and/
or root cause report
Omission of primary coolant hydrogen concentration measurements • • 0
Initiation of annual maintenance of an emergency diesel generator at during
power operation
• • 0
INES
rating
4.1.2 Plant operation, events during operation
and prerequisites of safe operation
Compliance with the Operating
Limits and Conditions
The Loviisa power plant has kept the power plant’s
Operating Limits and Conditions (OLC) up to date.
STUK has assessed the OLC and their up-to-dateness
in connection with inspecting the modifications
and analyses carried out at the plant as well
as in connection with on-site oversight.
During 2011, Fortum submitted to STUK for
approval a proposed amendment to the Operating
Limits and Conditions regarding a decrease in the
limits for noble gas releases from Loviisa 1 and
Loviisa 2. The need for the amendment was created
by the fact that the doses resulting from the
releases are currently estimated using a different
calculation model and different weather data from
those used at the time the release limits were originally
calculated. STUK found the proposed amendment
to be acceptable.
In 2011, the power company applied for permissions
from STUK for four planned deviations from
the Operating Limits and Conditions. Two of the
applications were related to fault repairs, one to
tests on the new emergency diesel generator and
one to the periodic inspection of a chemical tank.
5
4
3
2
1
0
2002 2003 2004 2005 2006 2007 2008 2009 2010 2011
INES 1
Loviisa
Figure 5. INES classified events at the Loviisa plant
(INES Level 1 or higher).
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