The stored CO₂ is monitored through a combination of technologies and methodologies to ensure it remains securely contained. Techniques include the use of seismic monitoring to detect any movement of CO₂ within the geological formation, and wellbore monitoring to check the integrity of the wells used for injection. Soil, air, and water samples may also be regularly taken to detect any potential leaks. The data collected is analysed to ensure the CO₂ is securely stored, and to take corrective actions if any anomalies are detected, ensuring the safety and effectiveness of the CCS process.

Implementing CCS incurs significant initial investment and operational costs for industries. These include expenses for the installation of capture technologies, construction of transportation infrastructure, and development of storage facilities. However, CCS can also offer economic benefits. For instance, captured CO₂ can be used for enhanced oil recovery, generating additional revenue. Moreover, as regulatory frameworks around the world become stricter regarding emissions, CCS can help industries avoid penalties and comply with regulations. The economic implications, therefore, depend on a balance between the costs of implementation and operation, potential revenues from utilised CO₂, and the avoided costs related to emissions penalties.

CCS can be applied to a variety of power plants and industrial facilities, but its applicability depends on several factors including the type of fuel used, the age and design of the facility, and economic considerations. For instance, coal-fired power plants and natural gas processing plants are prime candidates for CCS implementation. However, retrofitting older facilities with CCS technologies can be challenging and expensive. Each facility requires a customised approach to integrate CCS, considering the specific operational, technical, and economic parameters to ensure that the CO₂ capture, transportation, and storage processes are efficient, safe, and cost-effective.

Technology innovation is pivotal in enhancing the efficiency of CCS. Advancements in capture technologies, like the development of more efficient chemical solvents or membranes, can increase the purity and volume of CO₂ captured while reducing energy consumption. Innovations in machine learning and artificial intelligence can optimise operational processes, leading to cost reductions and enhanced safety. Furthermore, improvements in monitoring and maintenance technologies ensure the integrity of transportation and storage infrastructures, reducing the risk of leaks and environmental contamination. Each innovation contributes to making CCS more viable, scalable, and integral in reducing greenhouse gas emissions.

The purity of CO₂ significantly impacts the efficiency of the CCS process. High-purity CO₂ requires less processing and energy for compression and transportation, making the storage process more efficient and cost-effective. Impurities can lead to complications, such as corrosion of transportation pipelines and increased energy requirements for compression. Therefore, achieving a high level of CO₂ purity is crucial. It reduces operational challenges and costs, enhances the safety and integrity of the transportation infrastructure, and ensures that the stored CO₂ remains stable and secure in the underground storage sites.