**3.2 Risk during transportation**

According to a study by the Pipeline & Hazardous Materials Safety Administration (PHMSA) of the U.S. Department of Transportation (US DOT), in that country in 2008 there were 5,580 Km of carbon pipelines in operation, mainly involving enhanced oil recovery (EOR) projects. These pipelines are located in North Dakota (ND), Wyoming (WY), Utah (UT), Colorado (CO), New Mexico (NM), Texas (TX), Oklahoma (OK), Mississippi (MS) and Louisiana (LA). Most of these lines cross sparsely populated regions, a characteristic that reduces the severity factor of the risk associated with transporting the CO2. This is clearly intended, since the severity reflects the direct effects of possible accidents on people. Nevertheless, while effects on natural biomass may not directly affect local populations, they can cause secondary effects on more distant population centers. If these effects are neglected for not being direct, the losses can be greater and broader in scope, ceasing to be local and becoming regional.

In densely populated and highly industrialized regions such as Central and Northern Europe, carbon pipelines linking CO2 sources with storage sites will have to traverse populated areas, potentially prompting public opposition. The current risk perception places the risks of onshore storage above those of onshore transportation. This is understandable because people have lived for decades with oil and gas pipelines but are not accustomed to the idea of having geological formations beneath their feet containing millions of tonnes of CO2 "ready to escape". But while onshore storage projects may face low acceptance, offshore projects require a much greater investment in constructing the necessary pipelines.

Failures of carbon pipelines can be caused by holes or complete ruptures. In both cases the failure can be the result of:

Corrosion;

252 Fossil Fuel and the Environment

manage the risk of a CCS project. This imposes the need for an adaptive intelligence able to

The complexity of managing the risks of a CCS process depends on a series of aspects

The varying combination of these aspects will determine the analyses that must be

Due to their individual character, the risks of these steps are similar to those involved in the industrial process that will be the source of the CO2. In the case of Weyburn, the CO2 comes from the coal gasification plant in Beaulah, while in the Sleipner project it comes directly from the natural gas production well. In any event, the addition of CO2 separation, dehydration and compression units increases the complexity of the endeavor, raising the

According to a study by the Pipeline & Hazardous Materials Safety Administration (PHMSA) of the U.S. Department of Transportation (US DOT), in that country in 2008 there were 5,580 Km of carbon pipelines in operation, mainly involving enhanced oil recovery (EOR) projects. These pipelines are located in North Dakota (ND), Wyoming (WY), Utah (UT), Colorado (CO), New Mexico (NM), Texas (TX), Oklahoma (OK), Mississippi (MS) and Louisiana (LA). Most of these lines cross sparsely populated regions, a characteristic that reduces the severity factor of the risk associated with transporting the CO2. This is clearly intended, since the severity reflects the direct effects of possible accidents on people. Nevertheless, while effects on natural biomass may not directly affect local populations, they can cause secondary effects on more distant population centers. If these effects are neglected for not being direct, the losses can be greater and broader in scope, ceasing to be

In densely populated and highly industrialized regions such as Central and Northern Europe, carbon pipelines linking CO2 sources with storage sites will have to traverse populated areas, potentially prompting public opposition. The current risk perception places the risks of onshore storage above those of onshore transportation. This is understandable because people have lived for decades with oil and gas pipelines but are not accustomed to the idea of having geological formations beneath their feet containing millions of tonnes of CO2 "ready to escape". But while onshore storage projects may face

accompany this dynamic interplay of factors.

Characteristics of the storage reservoir;

Substances that form the gas to be injected.

 Separation technology; Separation and injection flow;

Monitoring technology; and

**3.2 Risk during transportation** 

local and becoming regional.

undertaken.

inherent to each project, among them the following:

 Distance between the separation and injection sites; Injection purpose (besides carbon sequestration);

**3.1 Risks in the separation, dehydration and compression steps** 

cross-risks and consequently changing the risk analysis drastically.


The climatic and geological aspects of the area where a carbon pipeline is or will be installed directly influence the effects suffered by the materials used in their construction. Besides this, these aspects also influence the choice between a buried or aboveground pipeline. In the case of failure of a high-pressure underground pipeline that causes a large leak, the pressure will fall rapidly, releasing a large quantity of energy. This energy will cause the soil above to be ejected, potentially resulting in large damages to structures and loss of lives.

Accidents in densely populated areas represent a greater risk both in terms of probability and severity. This fact requires a larger investment in security and ongoing monitoring of urban expansion in the areas through which the pipeline passes.

The main aspects that influence the amount of CO2 that can escape during an accident are: internal diameter of the pipeline, size of the hole, operating temperature and pressure and distance between shut-off valves.

Because CO2 is heavier than air, when released in large quantities it behaves differently than gases that are lighter than air. The release of CO2 occurs in the form of a cloud that moves near the ground and its progress depends closely on the local topography and weather.

The most important aspect to be analyzed is the impact of CO2 leaks on human health. In this respect, the concentration and exposure time are the two factors that must be assessed. A CO2 concentration of 150,000 parts per million (ppm), or 15% by volume, can cause a person to lose consciousness in less than one minute. Exposure for one hour to concentrations between 100,000 and 150,000 ppm can cause mortality ranging from 20% to 90% (Koornneef et al., 2010).
