Carbon capture and sequestration (CCS) is a critical strategy proposed for combating climate change. It involves the injection of CO2, a greenhouse gas, generated by coal-fired power plants and industrial facilities deep beneath the earth’s surface for long term storage.
There are potential significant issues with CCS, including:
- 1. Pollutants from the plant mixing with the CO2 that is injected leading to contamination of water supplies;
- 2. Potential mobility of CO2 once it is injected; and
- 3. Corrositivity of CO2 may result in release of subsurface contaminants into drinking water supplies
The Department of Energy and Coal State’s are betting heavily on the success of carbon sequestration. Federal funds are supporting some 25 projects around the country that will investigate the feasibility of CCS.
To address the concerns with CCS, U.S. EPA and the States are beginning to develop regulations for CCS projects. This Summer major developments include release of U.S. EPA’s rules and the issuance of an Underground Injection Control (UIC) permit by Ohio EPA for an Ohio test site.
Beginning this month, the Midwest Regional Carbon Sequestration Project (MRCSP) is utilizing FirstEnergy’s R.E. Burger Plant as a test site for injection of up to 3,000 tons of CO2. As reported on the MRCSP web page, the period of injection could vary from three to eight weeks, depending on the properties of the injection zones and the time needed for experimental set-up, regulatory oversight and monitoring.
The injection follows Ohio EPA’s issuance on September 2, 2008 of a permit to allow the installation and pilot testing of the underground injection well for purposes of carbon sequestration. This is the first permit issued in Ohio that would allow injection of CO2 subsurface for purposes of carbon sequestration. Some interesting aspects of the permit include:
- Injection will occur at three different geologic locations- the intervals range from 5,923 feet to 8,274 feet below surface. The intervals are selected to prevent mobility of the injected CO2.
- Closure financial responsibility– Total project closeout including closure of the well in accordance with regulatory requirements were estimated at $75,000 to $100,000. This amount only covers sealing of the well. No money is set aside in the event any other issues arise. Some may question whether this is sufficient financial assurance if it was anything other than a test site.
- Monitoring of Injected Fluids– On a quarterly basis, the injected material will be analyzed for various contaminants including SO2, NOx, particulate matter, and mercury. The monitoring is an attempt to verify contaminants from the plant are not mixed with the injected CO2.
Issuance of the permit precedes finalization of U.S. EPA proposed rules governing regulation of carbon sequestration projects. U.S. EPA’s proposed rules and Ohio EPA’s permit rely on similar legal authority on the Safe Drinking Water Act (SWDA). The permit together with the proposed rules give insight into how CCS projects could be regulated in the future. Areas covered by both the permit and U.S. EPA’s proposed rule include:
- Geologic site characterization to ensure that wells are appropriately sited
- Requirements to construct wells in a manner that prevents fluid movement into unintended zones;
- Periodic re-evaluation of the area around the injection well to verify that the CO2 is moving as predicted within the subsurface;
- Testing of the mechanical integrity of the injection well, ground water monitoring, and tracking of the location of the injected CO2 to ensure protection of underground sources of drinking water;
- Extended post-injection monitoring and site care to track the location of the injected CO2 and monitor subsurface pressures; and
- Financial responsibility requirements to assure that funds will be available for well plugging, site care, closure, and emergency and remedial response.
While the regulations and permitting of CCS are moving forward, not everyone is embracing CCS. In recent testimony before the U.S. House of Representatives Energy and Commerce Subcommittee on Environment and Hazardous Materials, serious concerns were raised by the American Water Works Association (AWWA) about the potential effect CCS technology may have on the nation’s underground sources of drinking water. Strong regulations and successful pilot tests will go a long way to addressing these concerns.