Geology Reference
In-Depth Information
the dependence of the tunnel progress entirely on the performance
and reliability of a single item of mechanical plant, which would
require a high level of technological input for its successful opera-
tion and maintenance.
-
Further details are given by Kim et al. (2001).
Table AE-1.2
Consequence
Catastrophic
Critical
Serious
Marginal
Negligible
Likelihood
Probable
15
12
9
6
3
Occasional
10
8
6
4
2
Remote
5
4
3
2
1
Score
Very high risk
-
not acceptable for tunnel construction
-
need to apply mitigation
measures to eliminate or reduce risk
10
15
-
High risk
apply mitigation measures to eliminate or reduce risk. Residual risk at this
level indicates need for active management control and response plans to be well
developed with well trained personnel, materials and plant readily available
-
6
-
9
Low risk
may be accepted if mitigating measures are in place under active
management control
-
1
-
5
