Another eight releases, whose cause is undetermined, were classified as minor by the Colorado Oil and Gas Conservation Commission — sheens, for example, coming off of a piece of equipment rather than a measurable volume of petroleum product.
Anadarko Petroleum Corp. on Wednesday reported the two larger releases in Weld County. About 125 barrels — or 5,225 gallons — spilled into the South Platte River near Milliken. A tank farm on the St. Vrain River released 323 barrels — or 13,500 gallons — near Platteville.
Both releases involve condensate — a mixture of oil and water — according to Matthew Allen, a spokesman for the Denver office of the Environmental Protection Agency.
"We are back in the field today looking for ongoing releases," Allen said. "So far, we haven't found any of those."
The Anadarko tank moorings held, company spokesman John Christiansen said, but strong waters and heavy debris appeared to have cracked pipes and manifolds, allowing the condensate to escape.
Anadarko was able to get absorbent booms and a vacuum truck to the Milliken site and collect about 40 barrels' worth of the 165 that had spilled, Christiansen said.
But floodwaters kept crews from reaching the tanks on the St. Vrain quickly. "By the time we got there, they were empty," he said.
The state oil and gas commission is trying to compile a comprehensive list of facilities in the flooded areas and their status, including what chemicals they had on site.
Companies are required by state law to report spills within 24 hours. "But they are moving faster than that with the flood," said Todd Hartman, a spokesman for the oil and gas commission.
Gov. John Hickenlooper, during a Thursday news conference on flood recovery, said the spills "weren't excessively large."
