Extinguish or Let It Burn?

Today, fire departments are faced more than ever with the decision of extinguishing a hazardous materials fire or letting it burn and weighing the environmental impact that decision may have. As always, life safety and protection of property are the primary decisive factors. A common type of incident is a gasoline tanker fire. This "let it burn" example is typical when life safety and protection of property do not play a role in the incident.

On Wednesday, Aug. 5, 2009, at 2:10 P.M., Lake Dillon, CO, Fire-Rescue was dispatched to a reported tanker fire at Mile Marker 223 on U.S. Highway 6 over Loveland Pass in Summit County. The steep, winding highway climbs above the timberline to the 11,990-foot mountain pass. This road is the primary hazardous materials transportation route through the county and is frequently the site of accidents and weather closures. Due to limited cell phone coverage in the area, the exact location and extent of the incident were in question. The fully loaded tanker was descending from the summit of the pass just past a sharp right-hand switchback when the trailer tipped and pulled the cab over with it, sliding across the eastbound lane and into a guardrail just at the timberline. It burst into flames and spilled fuel down an embankment. The spilled fuel then ignited, and the flames torched willow bushes while the fuel threatened a small high-mountain stream that forms the Snake River. The river flows into Dillon Reservoir, one of Denver's main drinking-water supplies.

Engine 11, a 1,500-gpm pumper with a four-person crew, responded from Station 11 in Keystone, 7½ miles away. Prior to the incident, Lake Dillon Assistant Chief Bruce Farrell left Station 11 enroute to Denver via Loveland Pass. Minutes after the initial dispatch, Farrell arrived on scene and reported a fully involved tanker truck at Mile Marker 223. Lake Dillon 3/Assistant Chief Kelly Greene and Battalion 8 Chief Travis Davis responded from Keystone. Engine 2 from Frisco was directed to pick up Tender 10, a 2,000-gallon tanker, and Engine 10, a 1,500-gpm pumper, from Station 10 in Silverthorne, 14.6 miles away. Farrell reported that the truck driver had been found and was not injured. He also advised that the truck was carrying flammable liquids consisting of varying amounts of gasoline and diesel fuel. Lieutenant Jason Bell was requested to respond from Dillon, 13 miles away, with Engine 8, a 1,500-gpm pumper, to provide additional manpower. Captain Andrew Hoehn from the Red, White and Blue Fire Department in Breckenridge called from the Frisco area and was directed to report to Station 8 in Dillon for coverage with Engine 7, a 1,500-gpm pumper.

Davis arrived on scene at 2:23 P.M., and established "Loveland Pass Command." Farrell reported that the truck was carrying 3,800 gallons of diesel fuel and 3,500 gallons of unleaded gasoline, and stated that two "BLEVEs" (boiling liquid, expanding vapor explosions) occurred just after he arrived on scene. Greene arrived a short time later and established the command post a half-mile below the crash site.

The primary incident objective was to contain the runoff to prevent it from entering the watershed and apply foam as needed to the brush at the bottom of the slope where the runoff was burning. Engine 11 arrived on scene at 2:34, and was directed to approach the site and give specifics on runoff, extent of fire and involvement of vegetation. This engine also established a drop-tank setup for the tender-shuttle operation just below the crash site. Engine 11 was designated as suppression and proceeded up to the site. Other command officers arrived on scene a short time later and were asked to assist with media, U.S.D.A. Forest Service, environmental health, Denver Water and all other notifications deemed necessary. Eventually, Lake Dillon Fire Chief Dave Parmley returned to the Basin area to assist with communications and Lake Dillon Deputy Chief Jeff Berino was reassigned to a smoke sighting north of Silverthorne.

Engine 8 arrived on scene and was briefed face-to-face on the objectives. They were assigned to assist with setting up the drop tank, advancing hoselines and mitigating the runoff as directed by the officer on Engine 11, Lieutenant Matt Brewer. Tender 10 and Engine Tender 10 arrived at 2:52. Greene advised the units of their traffic pattern and the fill-site location, three miles below the accident scene at the Arapahoe Basin Ski Area. The drop tank was set up and all crews were in place to mitigate any exposures.

Two Colorado State Police (CSP) hazmat officers arrived on scene and were briefed on the situation. After a thorough walk-through of the site, they confirmed the "let it burn" strategy and requested that an engine and the two tenders remain on scene while the remaining product burned off. At that time, Engine 8 was released to return to Station 8 for coverage which in turn released Engine 7. The driver of the truck was checked out by Summit County Ambulance 3 and later released to a fire department chaplain designee as arranged by Parmley. Lake Dillon Public Information Officer Steve Lipsher arrived on scene and dealt with the majority of the media contacts.

Firefighters used four sandbags and one traffic cone to construct an underflow dam downstream from the incident. Command was transferred to Brewer at 5:30 P.M., with a notification to CSP. Kelly and Davis cleared the scene at this time. Brewer conducted another face-to-face with CSP's hazmat officers and confirmed his action plan. CSP estimated that based on the remainder of fuel left in the tanker, the fire should burn out in 90 minutes to two hours. When the fuel burned out, CSP wanted Engine 11 firefighters to cool the remains of the fire so that the vehicle could be towed from the scene. Command briefed the remaining fire personnel of the action plan and evaluated the condition of the vegetation below the fire. Satisfied that there was no further threat to the vegetation in the area, command requested that the hoseline that had been staged below the fire be pulled back to the road surface for later extinguishment and cooling of the tanker. A second line that had been staged on the far side of the fire for exposure protection was picked up and all other unnecessary equipment was put back in service.

Command sent Firefighter Tom Adams below the fire to evaluate the underflow dam. Adams reported that the dam needed to be reinforced and that he had enough materials at the location to perform the work. Adams confirmed that the dam was functional and returned to the staging area. Approximately one hour later, the fuel fire had burned out and the remaining fire was localized to the tires of the tanker. Command was given the order from CSP to proceed with extinguishment and cooling of the tanker.

Firefighters Mike Waesche and Lou Laurina, wearing full personal protective equipment (PPE), began operations with a 1¾-inch handline. After cooling the front of the tanker, Waesche and Laurina repositioned to the outside of the guard rail to continue effective operations. Feeling that this was an unsafe area to operate from, command called firefighters back to the inside area of the guard rail. Command made contact with Colorado Department of Transportation (CDOT) officials on scene and requested that they use their front-end loader to pull the tanker from the guard rail so firefighters could safely continue operations. Command met with CSP and advised them of CDOT's actions. Bradley, the Engine 11 engineer, informed command that he was unable to provide Class A foam to the handline due to a clog in the system. Class B foam was flowed for about 10 minutes, which was enough to effectively extinguish and cool the burning tires. After final overhaul of the tanker, CSP was satisfied and advised that the fire department was released. Adams again evaluated the underflow dam and told command that it was working properly. Once all apparatus were back in service, "Loveland Pass Command" was terminated and all personnel cleared the scene at 7:12 P.M.

The 3,800 gallons of diesel fuel and 3,500 gallons of unleaded fuel were allowed to burn off without taking direct suppression action since it was confined to the accident scene. Any substantial application of water and foam would have resulted in downstream contamination due to the runoff of the water and unburned fuel. There was little threat of the fire spreading to the surrounding vegetation and the weather conditions were favorable to containing it to the roadway and unpaved shoulder with minimal burn over down the embankment.

Twenty-five to 30 gallons of Class B foam was used at the incident. Approximately 500 to 600 gallons of water was used. Damage was estimated at $175,000. The highway was closed for 24 hours while cleanup operations were completed and road repairs were made. There were no injuries.

JAY K. BRADISH/IFPA, Firehouse® news editor, is a former captain in the Bradford Township, PA, Fire Department. He has been a volunteer firefighter and fire photographer for more than 25 years.