Page 187 - Pipeline Risk Management Manual Ideas, Techniques, and Resources

7/164 Leak Impact Factor
C. Containment. Especially in the case of restricting the move- of emergency response in limiting spill size or dispersion for
ment of hazardous materials into the groundwater, quick specific segments of pipeline. The next step is to incorporate
containment can reduce the consequences of the spill. The those evaluations into the relative risk model.
evaluator should look for evidence that the response team By most methods of assessing the role of spill size in risk, an
can indeed reduce the spreading potential by actions 8-in. diameter pipeline presents a greater hazard than does a
taken during emergency response. This is usually in the 6-in. diameter pipeline (all other factors held constant). When
form of secondary containment. Permanent forms of sec- the leak detectiodemergency response actions can limit the
ondary containment are discussed in Chapter 1 1. spill size from an 8-in. line to the maximum spill size from a 6-
in. line, some measure ofrisk reduction has occurred. For sim-
Loss limiting actions plicity sake, risk reduction could be assumed to be directly
proportional to reductions in spill size and/or extent.
Proper medical care of persons affected by the spilled product Alternatively, and as a further assessment convenience, a
may reduce losses. Again, product knowledge, proper equip- threshold level of consequence-reduction capabilities can be
ment, proper training, and quick action on the part of the established. Below this threshold, credit would not be given in
responders are necessary factors. the risk assessment for emergency response capabilities. For
Other items that play a role in achieving the consequence- instance, the threshold could be: “reliable reduction of conse-
limiting benefits include the following: quences by at least 50% in the majority of pipeline failure sce-
narios.” When response activities can reliably be expected to
Emergency drills reduce consequences by 50% compared to consequences that
Emergencyplans would otherwise occur, the spill or dispersion score can be
0 Communications equipment adjusted accordingly. Failure to meet this threshold (in the
Proper maintenance of emergency equipment eyes of the evaluator) warrants no reduction in the previously
Updated phone numbers readily available calculated spill or dispersion scores.
0 Extensive training including product characteristics At first look, it may appear that an operator has many of
0 Regular contacts and training information provided to fire emergency response systems in place and they are fimctioning
departments, police, sheriff, highway patrol, hospitals, emer- to a high level. Realistically, however, it is difficult to meet a
gency response teams, government officials. criteria such as a 50% reduction in the effective spill size. The
spill and dispersion scores assess the amount of product spilled,
These can be thought of as characteristics that help to assuming worst case scenarios. To reduce either of these, emer-
increase the chances ofcorrect and timely responses to pipeline gency actions would have to always take place quickly and
leaks. Perhaps the first item, emergency drills, is the single effectively enough to cut either the volume released or the
most important characteristic. It requires the use of many other extent of the spill in half.
list items and demonstrates the overall degree of preparedness The evaluator can take the following approach to tie this
ofthe response efforts. together to calculate the liquid spill score. An example follows.
Equipment that may need to be readily available includes
Step I: The evaluator uses the worst case pipeline spill scenario
Hazardous waste personnel suites or a combination of scenarios from which to work. She cal-
Breathing apparatus culates the worst case as a spill score based on a l-hour, full
Containers to store picked up product bore rupture.
Vacuum trucks Step 2: The evaluator determines, with operator input, methods
Booms to attain a 50% risk reduction such as reduce spill amount by
Absorbant materials 50%, reduce population exposure by 50% (number ofpeople
Surface-washing agents or duration of exposure), contain 50% of spill before it can
Dispersing agents cause damage, reduce health impact hy 50%.
Freshwater or a neutralizing agent to rinse contaminants Step 3: The evaluator determines if any action or combination
Wildlife treatment facilities. of actions can reliably reduce the risk by 50%. This is done
with consideration given to the degree of response prepared-
The evaluator/operator should look for evidence that such ness.
equipment is properly inventoried, stored, and maintained.
Expertise is assessed by the thoroughness of response plans If she decides that the answer in Step 3 is yes, she improves
(each product should be addressed), the level of training of the liquid spill score calculated earlier to show only one-half of
response personnel, and the results of the emergency drills. the previously-assumed spill volume.
Note that environmental cleanup is often contracted to compa-
nies with specialized capabilities. Example 7.3: Adjustments to the liquid spill score
(Case A)
Assessing emergency response capabilities
The evaluator is assessing a section of gasoline pipeline
Many emergency response considerations have been men- through the town of Smithville.
tioned here. The evaluator should examine the response possi- The scenario he is using involves a leak of the full pipeline
bilities and the most probable response scenario. The best flow rate. This hypothetical leak occurs at a low point in the line
evaluations of effectiveness will be situation specific-the role profile, in the center of Smithville. He recognizes the acute