California regulators are launching an investigation into offshore fracking after revelations that the practice had quietly occurred off the coast since the late 1990s.
California Coastal Commission staff member Alison Dettmer says the agency has begun looking into the extent of hydraulic fracturing in federal and state waters.
Dettmer says the potential risks are not fully known.
The practice involves pumping large amounts of sea water, sand and chemicals to break up rock formations to recover oil and gas.
A recent report by The Associated Press documented at least a dozen instances of hydraulic fracturing in the Santa Barbara Channel, site of a disastrous 1969 oil platform blowout that spurred the modern environmental movement.
The coastal panel discussed fracking Thursday during its meeting.
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