Environmental impact

Studying environmental impacts of CO2 at a mofette Source: BGR

The impact of potential CO₂ leakage on human health, safety and environment (HSE) can be assessed by studies of natural analogues and field experiments:

• At natural CO₂ emission sites such as mofettes or CO₂-rich springs, e.g. in the Eifel region, adaptations of microbes, plants and animals to elevated CO₂ concentrations can be studied. In the deep biosphere, bacterial adaptations can also be examined in natural CO₂ reservoirs.
• In the case of leakage, monitoring of CO₂ is required by the emission trading regulations but also for HSE management and control of remediation actions. BGR is developing and testing mobile or fixed monitoring stations for CO₂ concentrations and fluxes within air, soil, rock, and water. Values recorded by the stations are needed for the interpretation of ecosystem response to soil gas dynamics at test sites such as the Ketzin storage.
• Microbial communities may be affected by CO₂ leakage into soils and also in the deep storage formations. In the latter, growth of microbial communities will affect well and storage formation properties.
• In field experiments known amounts of CO₂ are injected into the subsurface under controlled conditions. Short term-proceeses and impacts on soil and benthic microbes were studied by BGR in field tests in Great Britain and offshore Norway.
  

Apart from the CO₂ itself, displaced formation brines could also potentially impact the environment. To assess this risk, BGR carries out numerical simulations and examines potential brine migration pathways.

To help protect valuable natural resources, such as important groundwater aquifers or nature protection areas, these resources are mapped and juxtaposed against potential CO₂ storage areas. This information allows consideration of these resources for appropriate site characterization and monitoring plans and for the planning of preventive measures.

BGR cooperates with national and international partners on all of these issues, using the results for the development of guidelines on CO₂ storage safety and monitoring.

Past projects:

• CO₂GEONET European Network of Excellence on Geological Storage of CO₂ (in German only)
• NASCENT Natural Analogues for the Study of CO₂ in the Geological Environment (in German only)
• COOSKA Quantifizierung geologischer Speicherkapazitäten für die Einlagerung von CO₂ (COO SpeicherKApazitäten)
• RISCS Research into impacts and safety in CO₂ storage
• CLEAN CO₂ Large-Scale Enhanced Gas Recovery in the Altmark Natural Gas Field (in German only)
• RECOBIO II Untersuchung der biogeochemischen Transformation von im tiefen Untergrund gespeichertem CO₂
• CO₂GeoNet Association European Network of Excellence on Geological CO₂ Storage (in German only)