Washington DC - Federal regulators released draft rules governing the long-term underground storage of carbon dioxide last Tuesday, laying the foundation for what may become a tool to limit human impact on the environment.  The proposed rules, which outline storage siting, testing, and monitoring requirements, fall under EPA’s existing Underground Injection Control (UIC) program. They would update the 1974 Safe Drinking Water Act.

Would Add to Existing Rules

The agency’s proposal is based on existing rules protecting underground drinking water, but it also seeks to prevent CO2 injected thousands of feet below the Earth’s surface from seeping back to the top.

The agency said it wants to ensure that stored CO2 does not
move and does not leach heavy metals or other contaminants
out of surrounding rock into underground water. Benjamin
Grumbles, EPA assistant administrator for water, told
reporters in a teleconference call from Washington, DC, on
July 15 that a final rule is expected in late 2010 or early
2011.

“With proper site selection and management, carbon
sequestration could play a major role in reducing greenhouse
gas emissions while protecting underground water sources.” 

Rules already exist for CO2 injected for enhanced oil
recovery projects. Grumbles said the proposed new regulations
represent the first federal regulations for long-term storage
of CO2. EPA will accept public comment on the Advance Notice
of Proposed Rulemaking for 120 days following its
publication. The proposed rules come as Congress contemplates
carbon capture and storage (CCS) technology.

CCS is being considered as a way to contain greenhouse gas
emissions from power plants and other industrial sources, but
the technology is not yet available on a large-scale
commercial basis.

CO2 Underground Storage

The process of storing CO2 underground is relatively simple:
A shaft is drilled thousands of feet into the ground, much
like any oil or natural gas well, and into a formation that
can hold CO2. The gas is then pumped into the hole, where it
becomes trapped. The well is sealed off, and the area above-
and below ground is monitored.

CO2 has been injected into older oil formations for many
years to improve production, but most of that CO2 comes from
naturally occurring sources, not industrial emissions. There
are already federal rules aimed at ensuring those injections
don’t contaminate groundwater, but before this week no rules
were aimed at keeping the CO2 from coming back to the surface.

EPA Working With Dept of Energy

“This rule paves the way for technologies that will protect
public health and reduce the effects of climate change,”
Grumbles said.

The agency worked with the US Department of Energy,
Department of Agriculture, and Department of Transportation
to develop new regulations to cut greenhouse gas emissions
from motor vehicles and their fuels.  EPA and DOE jointly
fund the Lawrence Berkeley National Laboratory (LBNL) to
study potential impacts of CO2 injection on aquifers and
drinking water sources.

LBNL also is assessing potential changes in regional        
groundwater flow, including displacement of pre-existing
saline water or hydrocarbons. Grumbles said EPA tracks the
progress of national and international sequestration
projects, including DOE’s Regional Carbon Sequestration
Partnerships.Under the UIC program, experimental technology
permits have been issued for CO2 injection wells drilled by
the sequestration partnerships, the EPA offical pointed out.

Injection Well Types

EPA proposes a new class of injection wells for carbon
sequestration. UIC regulations outline five classes of
injection wells. The proposed rules would establish a sixth
class specifically for long-term CO2 storage.  Grumbles said
the proposed rules would apply to CO2 injection wells onshore
and in state territorial waters within 3 miles of the US
coast. Any CO2 wells to be drilled in waters beyond the
3-mile limit would fall under the Marine Protection,
Research, and Sanctuaries Act.  Many states already have
proposed CO2 storage regulations.

Grumbles said EPA wants to provide “consistent national
standards that allow for flexibility working with the
states,” and that the proposed rules would provide a minimum
level of safeguards.