Securing logistical connections to a nuclear power plant,
especially in exceptional circumstances, is an important
part of nuclear safety. This report considers the
schedule risk of clearing a road transport route to the
Hästholmen nuclear power plant site after a storm as cut
down trees that block some essential roads.
The local road network is described. A coarse inventory
is made of the trees that might block traffic on a road
in this network if they fell on it in a suitable angle.
The work process of a fireman crew clearing the road is
presented, and an activity network model of the process
is formulated. A Monte Carlo simulation model of the
network, with probabilistic distributions for the
durations of individual activities, is implemented in
Microsoft Excel and analysed. The model describes one
scenario, where a west storm has fallen down trees.
To illustrate the use of an emergency operations model in
decision support, two alternative courses of action are
modelled and analysed: one in which a single fire crew
clears Atomitie, and another where the fire foreman,
after situation assessment, calls another crew to clear
Lappomjärventie which constitutes a parallel route to
Hästholmen for much of Atomitie's length.
The model class, activity networks, and the analysis
method, Monte Carlo simulation, are useful in analysing
schedule risks of operations. However, a comprehensive
analysis requires the analysis of more weather scenarios,
a more detailed analysis and representation of various
alternatives of the clearing process, more attention to
the probability that a wind of certain speed can fall
down a given tree, and other considerations.
|Series||VTT Research Report|
- prevention and emergency operations
- mathematical modelling
- nuclear safety
- probabilistic risk analysis