Environmental Risk Assessment of Oil and Gas Activities

Environmental risk assessment investigates all planned streams of waste, emissions to air and discharges to land and sea. Accidental, unplanned events are also investigated. Accidental initiating events are defined by risk analysis.

To ensure that environmental issues are comprehensively identified, an environmental issues identification (ENVID) meeting is usually held, especially for more complex projects, where a team participate in structured brainstorming under the guidance of one of our environmental specialists.

Existing environmental status and sensitivities are defined by data collection exercises, either desk studies or field surveys.

For desk studies, environmental data is collected and analysed from multiple sources within national and international arenas. The sources to be researched typically include:

• government departments and public bodies;
• specialised trade associations, federations, institutes and organisations;
• international organisations;
• university, government and trade libraries.

When existing data are inadequate, surveys are commissioned to obtain specific information on the status of the environment in the project area.

The principal environmental risks during construction are associated with disturbance to the ecosystem. Such impacts are capable of proving short-term, long-term or even permanent. During testing and pre-commissioning, the disposal of chemically treated hydrotest water can be an environmentally sensitive issue.

The principal operational risks are usually associated with leaks and spillages, howsoever caused. Given that good practice in the engineering design is directed to prevent leaks and spillages, all such occurrences must be regarded as unplanned events. Potential environmental risks during operations are reviewed with reference to adverse impacts upon air, water and land, and upon flora and fauna.

Based upon the analysis of the frequency and severity of events that may affect the environment, a project philosophy is normally derived in respect of:

• monitoring/recognition;
• response;
• emergency procedures;
• containment;
• minimisation of impacts;
• remediation.

Based on the above approach the risks towards the environment can be classified and prioritised. From the prioritisation, combined with the likelihood of an event predicted in the safety assessment, an evaluation can be made of the significance of each risk. From that, conclusions can be drawn of the economic viability of a particular level of investment to minimise each risk.