Page 368 - Pipeline Risk Management Manual Ideas, Techniques, and Resources

Risk mitigation 15/343
focus, coupled with the increased understanding ofthe underly- mizing potential consequences is usually more difficult
ing risk issues, will usually lead to more detailed strategies for because it would involve changing some aspect of the product
overall risk management. stream and/or the pipeline’s surroundings to effect the greatest
change. Emergency response and leak detection are, however,
Prioritization very realistic opportunities to reduce consequences.
By its nature, the risk assessment model points to risk miti-
The scores from the risk assessment should represent the best gation opporhmities. Each variable that is measured as a risk
information available on each pipeline section. Basing prioriti- contributor can, at least theoretically, be changed to effect a
zation and resource allocation decisions on the risk scores is reduction in risk. In practical terms, changing certain items are
therefore a defensible, traceable process. The highest and of course much more attractive than others.
lowest rated pipeline sections from a prioritized risk ranking For example, when pipe replacement is considered as a risk
are significant to risk management. Because the lowest scores reduction option, preference should obviously be given to the
show the lowest safety (highest risk), a disproportionate higher risk sections. If increased cathodic protection is consid-
amount of resources is justifiably spent on them. Recognizing ered as an option to prevent corrosion damage, preference
that the amount of resources is limited reducing the spending should be given to higher risk sections, possibly even to the
on the safest sections in order to improve the safety of the high- point of reducing or temporarily eliminating activities in low-
est risk sections may similarly be justified. This is especially risk areas. While intentionally increasing the risk in an other-
true for discretionary spending-the portion of the budget that wise safe area should only be done after careful and thoughtful
can be allocated on a basis other than regulated activities and analysis, it must be recognized that, when additional resources
direct revenue-generating activities. are not available, redistribution of existing resources may be
In prioritizing segments, it is important to look beyond the prudent.
summary numbers such as the risk and index sum scores used in
this book. To ensure that a deficiency in an index is not being Consequence-dominated risks
masked by an excess in others, it is important to examine each
index independently, in addition to the overall index sum. This As noted before, it is usually preferable to reduce risk by
can also be done by converting the index sum scores into failure decreasing failure potential. Options for reducing potential
probability scores, to better capture the worst case index score consequences are normally fewer and more problematic.
as discussed on page 300. In either case, this examination can Examples of consequence reduction measures include chang-
be combined with the consequence (LIF) prioritization to ing the product type or pressure, installing secondary contain-
develop risk management strategies for each failure mode. ment, relocating the pipeline or removing receptors, reducing
the pipe diameter or flowrate, and improving leak detection and
Resource allocation emergency response. A pressure reduction somewhere on the
system would require significant changes elsewhere to ensure
At the center of risk management is the need to properly allo- adequate product deliveries. It is recognized that occasionally,
cate scarce resources. Managers strive to control the “right” options selected for reducing failure probability are not enough
risks with limited resources-there will always be limits on the to bring the risk level to an acceptable level (by whatever
amount of time, manpower, or money to apply. Risk can be acceptability criteria is chosen). If this occurs, the suggested
reduced through the allocation of new resources or through approach is as follows:
redistribution of the existing level of available resources. This
must be done with consideration given to often-conflicting 1. Determine to what level the index sum would need to be
factors such as increased in order for this risk to be brought in line with
“normal” risk exposures?
Availability of resources (money) to address the needs 2. Is this score level possible?
0 Relative risks that currently exist within the system 3. Is this score level feasible, with spending constraints consid-
0 The costs and benefits of various operations, maintenance, ered?
and capital expenditure choices
The rate at which improvement needs to progress. If it is determined that a high enough level of index sum is not
possible, investigate possible changes to LIE Changing the LIF
The rate of spending is a key issue in resource allocation. As means changing the potential consequences of a failure. The
spending is thought to improve the risk situation, questions answers to the following questions leads to possible LIF
arise as to how fast improvements should be made and, if changes:
resources are being reallocated, how much increased risk on the
currently safer sections can be tolerated. 0 Can the pressure be reduced?
A resource allocation strategy should be developed with the 0 Can the pipeline be rerouted?
risk assessment results serving as a key measurement of the Can the potential spill size be reduced?
effectiveness of the strategy. Can emergency response actions be upgraded to reliably
reduce consequence potential?
Mitigation options
As part of investigating more extreme measures. it is some-
In general, it is preferable to reduce risk by reducing the proba- times useful to convert the relative risk value to an absolute risk
bility of failure-variables in the index sum. Reducing or mini- value. This is discussed elsewhere in Chapter 14.