DENVER (AP) -- More spills were revealed Friday in a Colorado oilfield swamped by floodwaters as cleanup efforts remained stalled due to high waters and regulators cautioned that more oil releases were likely to be found in coming days.
The latest spills included 2,400 gallons of oil from a toppled storage tank, almost 900 gallons from an unspecified source and two others from damaged storage tanks that involved unknown volumes.
That brings the known volume of oil released since massive flooding began last week along Colorado's Front Range to an estimated 22,060 gallons -- about 525 barrels.
Most of the oil releases reported to date came from storage tanks or tank farms operated by Texas-based Anadarko Petroleum Co. At least four of the releases reported by the company were in Weld County and spilled oil into the South Platte River or a tributary, according to information submitted to regulators.
It's possible other companies have suffered similar problems since flooding began last week but have not yet been able to assess their damage. An aerial survey of the flood area on Thursday revealed up to two dozen overturned oil storage tanks, state regulators said. Releases from those tanks could not be immediately confirmed.
With many roads in the area washed out, the sites remained largely inaccessible, preventing cleanup work from getting underway until water levels drop, said Anadarko spokesman John Christiansen.
"We've got a couple of amphibious vehicles and flat-bottom boats that we're using, but really until things have a chance to dry out and some of the infrastructure issues are sorted out, it's going to be difficult," Christiansen said.
Authorities in Weld County have said their concern over spilled oil is eclipsed by much greater volumes of sewage and other contaminants washing into local waterways.
In other developments:
-- The number of people unaccounted for dropped to around 80 thanks to door-to-door searches and restored communications. Seven people have died and three others are missing and presumed dead.
-- FEMA has approved $8 million in aid for homeowners and the number of FEMA personnel on the ground increased from 250 to 800.
-- The new official in charge of recovery efforts, IHS Inc. executive chairman Jerre Stead, said his priorities are rebuilding the affected area equal or better than it was before.
-- Gov. John Hickenlooper approved another $20 million in emergency flood funding, bringing the total to $26 million, and expanded the disaster zone to include a total of 17 counties.
-- Schools are making arrangements for students in flooded towns to head back to class. Students in Lyons will attend school in nearby Longmont starting next week while students in another mountain town may have a teacher sent to them.
Brown reported from Billings, Mont.
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