US-36 HazMat Spill Update

MON MAY 3 2:00 PM UPDATE

The Town of Lyons and the Lyons Fire Protection District continues to communicate up to date information regarding the hazardous material spill that happened on Tuesday, April 27 around noon time, along US-36 westbound just before the Apple Valley Bridge. 

EPA remains at the scene of the April 27th gasoline tanker rollover spill northwest of Lyons, Boulder County, CO.  The agency’s response team continues to focus on the removal, containment, and monitoring of residual gasoline in soils adjacent to the roadway and the banks of North Saint Vrain Creek.  In addition to EPA and the Colorado State Patrol, other agencies involved in the response include: Colorado Department of Transportation, Colorado Department of Public Health and Environment, Colorado Parks and Wildlife (CPW), Boulder County, Lyons Fire Protection District, and Town of Lyons.

As contaminated soils are removed, the area is backfilled with clean fill material.  EPA expects this work to be completed within the next few weeks.  Initial reclamation and restoration of part of the area has begun and will continue this week. 

Some residual gasoline remains trapped in the surface of sediments along the bank of the creek and wisps of sheen can be observed upon stirring the sediments.  EPA anticipates this residual will gradually dissipate over the next few weeks, depending on the weather and water levels.  EPA will monitor the natural attenuation of the residual gasoline over the next few weeks.

It is important to note, this residual is slight and is minimally detectable to undetectable in water quality sampling.  EPA’s water quality sampling on April 27 and 28, for example, did not detect any lingering contamination in water quality in the North Saint Vrain Creek.  While visible to the naked eye, a bright-colored or “rainbow” sheen is approximately 0.3 microns thick.  For perspective, a human hair is 70-100 microns thick. 

Gasoline odors may also be detected along the Creek, especially near the site of the rollover.  These odors will also dissipate with time and sunshine. 

Gasoline may have also migrated into soils beneath Hwy 36.  These soils are inaccessible without risking damage to, and removal of, the highway.  Consequently, containment booms will be left in place around the nearby culvert to contain any discharging product or sheen in the creek.  This area will be monitored on a weekly basis. 

On May 1, as part of their assessment on the impacts of the gasoline spill, CPW conducted a micro-invertebrate, fish, and algae study of the creek.   All concerns and questions regarding this assessment effort should be directed to the CPW.  Questions from the public, as well as pictures of the fish kill, can be sent to:  LyonsFishInfo@state.co.us.

For more detailed information on EPA’s efforts, including background and a sampling data map, please visit the EPA’s response website 

• Environmental Protection Agency Response Site
• Interactive Story Map (EPA)
• Well water testing (Apple Valley Residents)
• COTrip.org (road closure information) 

If we have more updates to share we will post these public information releases and briefings via the Town E-blast. 

We remind all residents in the Town of Lyons to please sign up for the Boulder County emergency messaging system.