EPA says Tuesday tanker spill near Lyons leaked more fuel than thought; 'unexpected' gasoline pockets discovered in soil

May 1—The Environmental Protection Agency said crews expected to be working overnight Friday, after "unexpected" free-flowing pockets of gasoline were found in the soil, near the site of a semi tanker spill outside of Lyons. EPA officials also said in a news release that the amount of fuel released may have been more than initially estimated, with 1,000 to 1,600 gallons believed to have leaked, instead of the initially predicted 500 to 1,000 gallons.

Dana Barnicoat, EPA Region 8 public information officer, said that the fuel was discovered by the responsible party's contractors while excavating gasoline-contaminated soil. Barnicoat said officials didn't yet know how much fuel was in the pockets.

"In order to address the pocket of product, the (responsible parties) contractor is bringing more resources on site and we are going to work through the night tonight," Barnicoat said in a statement. "There is weather coming in on Sunday, so unified command are hoping to be able to complete the clean up in advance of the storm and re-open the road."

The name of the trucking company has not been released.

Friday's activity is among the latest efforts to clean up in the aftermath of the rollover Tuesday on U.S. 36. The semi tanker was hauling 8,500 gallons of gasoline when it crashed on a curve near Apple Valley Road's north intersection at the highway, northwest of Lyons.

Despite officials discovering more fuel may have leaked than initially expected, the EPA said in its release that the "revised estimate does not change EPA's assessment that the pulse of gasoline has dissipated and our sample results suggest no lingering contamination in the creek."

The Lyons Fire Protection District was on scene Friday to provide 24-hour fire watch, the release said, to respond to any fires that may spark during the excavation of "gasoline soaked soil."

"Gasoline contaminated soils are easily ignitable and several small fires were ignited on April 28 during excavation of the most contaminated soils," the release said.

The EPA's release said that contaminated soil will be stored on-site pending disposal. The area will be "re-secured with concrete or flowable fill."

The EPA reported that there was "significant fish kill" after an unknown amount of fuel leaked into the North St. Vrain Creek, which is on the opposite side of the highway from the crash site. Dead fish were found as far as three to four miles from the site of the spill. Colorado Parks and Wildlife spokesperson Jason Clay said Thursday that it will take the wildlife agency time to gather data on the number of fish killed.

'When in doubt stay out'

Lyons officials on Friday removed signs along the North St. Vrain Creek warning people that the water may be hazardous to their health.

The signs placed along the creek bank said: "Avoid the river, per EPA may be hazardous to health." Victoria Simonsen, town administrator, said that they were given the "all clear" to remove the signs Friday.

"The message to residents and visitors is if you smell gasoline or see a sheen on the water, you should not go in," Simonsen wrote in an email. "The county is using the slogan: 'When in doubt, stay out.'"

Simonsen also said that according to the EPA, two fingerling fish, were discovered in the town section of the stream Thursday, which she said was "a good sign."

Work continues through weekend

The EPA reported Thursday that there were "no indications of lingering effects to the water quality." Despite that, Valeriy Bizyayev , EPA on-scene coordinator, said crews need to remain on site.

"Even though there's nothing wrong with the water now we have to make sure that we leave it like that," Bizyayev said. "If we walk away now, there could potentially be gasoline that makes it in as the rains come through and flushes everything, so we're here to make sure we do it right."

Exposure to sunlight and the churning of the river, Bizyayev said, have helped to break the gasoline down and flush it away.

"Gasoline is a really volatile product," Bizyayev said. "It doesn't stay there very long and nature does a fantastic job of breaking it down. That's why now there's not an impact to the water quality is that because of how light and volatile these things are is because they move through the environment quickly."

Water quality samples, Bizyayev said, emphasize this.

"All of the results we've gotten back, so far, have indicated that there is no long-term impact," Bizyayev said. "We haven't seen anything above any our drinking water standards, which is really good. We do have some minor hits of gasoline range organics in the water, but they're nothing of concern — it could have also been run off from the road. It's not a sustaining or long-term impact."

The release Friday said that the EPA received numerous requests to sample water wells along Apple Valley, as well as concerns about the spill's impact on the local fishery. On Tuesday and Wednesday, samples were taken from a water well about 20 feet from the site of the spill. EPA officials also took three sediment samples along the river. The release said that "sample results did not detect any lingering contamination."

People can view the results of the EPA's sampling of the water and see a map of the location's they were drawn from online at bit.ly/335XDm9.

As of Friday afternoon, Barnicoat said that the discovery of free-flowing gasoline pockets didn't change the status of the water quality.

Bizyayev said containment booms remained in place to catch fuel so that it can be skimmed off the water. The bank opposite of the culvert was flushed with water Friday. He emphasized that there was "no continuous impact" to the water and that crews were essentially catching what was being cleaned.

Crews are expected to continue work at the spill site throughout the weekend. The release said drivers and outdoor enthusiasts, including cyclists and runners, are encouraged to use alternate route through the area to help keep the highway open for emergency responders and cleanup equipment.

Colorado Parks and Wildlife seeks public's help

Anyone who finds dead fish in the creek is asked to send photos, videos and location information to the Colorado Parks and Wildlife at LyonsFishInfo@state.co.us.

For public health related questions or concerns, people can contact Boulder County Public Health at healthows@BoulderCounty.org