Remediation measures are applied in case a significant
irregularity in the behaviour of a storage site or a leakage of
CO2 from a storage site occurs. They can be divided into
three categories, depending on the nature of the event. The first
category applies to wells and includes well intervention techniques
that can mostly be based on proven practice from the oil and gas
industry. The second group refers to leakage through geological
pathways like caprock failures or faults. In this case the
remediation measures usually involve injection and pressure
management modifications and/or use of low-permeability "healing"
materials. The third case is leakage into overlying aquifers
(including potable groundwater resources and near-surface
structures) where techniques common in hydrogeology and pollution
control are considered.
A special group of newly developed techniques, directed
specially at remediation of CO2 storage sites, include
application of special materials (special cements, self-healing
substances, etc.) or specifically tailored aquifer management
techniques. These techniques are the subject of intensive on-going
research and development, and further improvements in this field
are expected in the near future.
Remediation measures are an integral part of regulatory regimes
for CCS in all relevant countries and regions where CCS activities
are on-going or planned. The CO2QUALSTORE guideline (Aarnes et al.,
2010) considers contingency and remediation planning an essential
part of the risk and uncertainty management, providing a systematic
approach to the issue. The European regulatory framework is based
on the EU CCS Directive (2009) and Guidance Documents 1 and 2
(2011). The key instrument is the risk-based and site-specific
corrective measures plan which has to be prepared by the storage
site operator as part of storage permit application.
The international comparison shows that most of the regimes are
based on similar foundations, closely linking risk assessment,
monitoring and remediation measures into one mutually
interconnected package. The European and U.S. legislations appear
to be the most detailed and most elaborated.
The main aim of geological storage(CO2) A process for retaining captured CO2, so that it does not reach the atmosphere of carbon dioxide is to safely and permanently store the captured CO2Carbon dioxide and prevent it from migrating out of the storage(CO2) A process for retaining captured CO2, so that it does not reach the atmosphere formationA body of rock of considerable extent with distinctive characteristics that allow geologists to map, describe, and name it and entering the atmosphereThe layer of gases surrounding the earth; the gases are mainly nitrogen (78%) and oxygen (around 21%). It is expected that wellManmade hole drilled into the earth to produce liquids or gases, or to allow the injection of fluids selected, sufficiently investigated and carefully operated and monitored storage(CO2) A process for retaining captured CO2, so that it does not reach the atmosphere sites will meet this target thanks to the various trapping(CO2) Containment or immobilisation of CO2, there are four main trapping mechanisms: structural or stratigraphic trapping; residual CO2 trapping (capillary trapping) by capillary forces; solubility trapping by dissolution of CO2 in resident formation fluids forming a non-buoyant fluid; and mineral trapping where CO2 is absorbed by solid minerals present in the storage volume mechanisms existing in the storage(CO2) A process for retaining captured CO2, so that it does not reach the atmosphere formationA body of rock of considerable extent with distinctive characteristics that allow geologists to map, describe, and name it.
It is, however, important to consider the probability that CO2Carbon dioxide may escape out of the storage(CO2) A process for retaining captured CO2, so that it does not reach the atmosphere formationA body of rock of considerable extent with distinctive characteristics that allow geologists to map, describe, and name it, migrate within the storage(CO2) A process for retaining captured CO2, so that it does not reach the atmosphere complex or even leak out of it into the shallower sub-surface or up to the atmosphereThe layer of gases surrounding the earth; the gases are mainly nitrogen (78%) and oxygen (around 21%). Although such an event would cast in doubt the CCSCarbon dioxide Capture and Storage technology and may also adversely affect the public acceptance of the technology; if it can be demonstrated that any such event can be remediated in a simple and cost-effective way, this would be very important for policy makers, regulators, site operators and the general public (Kuuskraa and Godec, 2007). It is, therefore, very important to have sufficient knowledge about what can be done if leakage(in CO2 storage) The escape of injected fluid from the storage formation to the atmosphere or water column from the storage(CO2) A process for retaining captured CO2, so that it does not reach the atmosphere formationA body of rock of considerable extent with distinctive characteristics that allow geologists to map, describe, and name it is detected. This chapter provides a brief summary of available remediation techniques and an overview of regulatory regimes related to remediation of leaking storage(CO2) A process for retaining captured CO2, so that it does not reach the atmosphere sites both in Europe and worldwide.