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2 Environmental Risk Management Applications …
Fig. 2.7 Environmental risk overview for various activities from a producing oil field in a high
activity year with several well operations and development drillings. Here, an example measured
against the operator’s own Risk Tolerance Criteria (RTC) and categorization
lowest impact (left to right), and a map showing the impact in grid cells from the
95-percentile worst-case simulation (Fig. 2.6, right).
An oil-producing installation case can have several DSHAs (i.e. a blowout, a
process leakage, a pipeline spill etc.) and each DSHA can consist of several spill
scenarios (i.e. a blowout can have different spill rates and durations with different
probabilities). Therefore, the risk results can be aggregated on the DSHA and
case level, with possibilities to look at specific contributions and details from the
underlying spill scenarios (Fig. 2.7). This will give valuable information towards
the understanding of risk-contributing activities and towards the planning of field
activities.
Once the risk has been established, the primary objective is to evaluate the risk
level and to communicate activity or scenario risk to stakeholders and decisionmakers in a logical and understandable way. ERAs are carried out with the purpose
to assess and ensure acceptable environmental risk for oil and gas offshore operations.
To ensure this, the risk level can be evaluated against risk tolerance criteria (RTC),
and/or properly informed decisions (e.g. using the ALARP principle) can be made
regarding the implementation of risk reducing measures to achieve a tolerable risk
level (IPIECA-IOGP 2013).
ERA Acute provides the necessary input to a traditional risk matrix by giving the
probabilities for different operator-defined damage categories (Fig. 2.8). In the risk
matrix, risk tolerance criteria define the threshold for a tolerable likelihood of an
environmental damage (EPA 2007; NORSOK Z-013 2001). Alternatively, risk can
be presented as a percentage of a certain RTC for different species or habitats, where
values above 100% represent risk level exceeding the RTC (NOROG 2007).
2 Environmental Risk Management Applications …
Fig. 2.7 Environmental risk overview for various activities from a producing oil field in a high
activity year with several well operations and development drillings. Here, an example measured
against the operator’s own Risk Tolerance Criteria (RTC) and categorization
lowest impact (left to right), and a map showing the impact in grid cells from the
95-percentile worst-case simulation (Fig. 2.6, right).
An oil-producing installation case can have several DSHAs (i.e. a blowout, a
process leakage, a pipeline spill etc.) and each DSHA can consist of several spill
scenarios (i.e. a blowout can have different spill rates and durations with different
probabilities). Therefore, the risk results can be aggregated on the DSHA and
case level, with possibilities to look at specific contributions and details from the
underlying spill scenarios (Fig. 2.7). This will give valuable information towards
the understanding of risk-contributing activities and towards the planning of field
activities.
Once the risk has been established, the primary objective is to evaluate the risk
level and to communicate activity or scenario risk to stakeholders and decisionmakers in a logical and understandable way. ERAs are carried out with the purpose
to assess and ensure acceptable environmental risk for oil and gas offshore operations.
To ensure this, the risk level can be evaluated against risk tolerance criteria (RTC),
and/or properly informed decisions (e.g. using the ALARP principle) can be made
regarding the implementation of risk reducing measures to achieve a tolerable risk
level (IPIECA-IOGP 2013).
ERA Acute provides the necessary input to a traditional risk matrix by giving the
probabilities for different operator-defined damage categories (Fig. 2.8). In the risk
matrix, risk tolerance criteria define the threshold for a tolerable likelihood of an
environmental damage (EPA 2007; NORSOK Z-013 2001). Alternatively, risk can
be presented as a percentage of a certain RTC for different species or habitats, where
values above 100% represent risk level exceeding the RTC (NOROG 2007).