Fire Behavior Associated with the 1994 South Canyon Fire on Storm King Mountain, Colorado
Fire Chronology (continued)
July 2 to Evening of July 5—Low Intensity Downslope Spread
Lightning ignited the South Canyon Fire on the afternoon of July 2, 1994, near the southernmost point on the Main Ridge. The fire was reported to the county sheriff at 1030 and to the BLM district office at 1100 on July 3, 1994. The fire burned primarily in the open pinyon-juniper fuel type, backing downslope in cured annual and perennial grasses with occasional upslope runs and torching. It grew to 11 acres by the evening of July 4 (fig. 19).
The fire burned through the night of July 4, growing to 29 acres by 0800 on July 5. It continued to spread down the slope in the surface fuels beneath the pinyon-juniper and Gambel oak through the day on July 5. The direction of spread was mostly to the north and west. Burning was not continuous and many unburned islands of fuel remained.
On July 5 seven BLM firefighters, including Incident Commander Blanco, walked into the fire from the East Drainage. They cut a helispot (H-1) and began direct downhill fireline construction. About 1500 an airtanker made a retardant drop on the fire burning on the steep rocky slope above the interstate highway. The BLM firefighters left the fire at 1730 to refurbish their equipment. They hiked out the West Drainage.
At approximately 1745, eight smokejumpers parachuted to the Drop Zone. Jumper-in-Charge Mackey later radioed Incident Commander Blanco that the fire was burning actively and had crossed the fireline prepared by the BLM crew earlier that day. After collecting their gear, the smokejumpers built a fireline along the east flank of the fire until the terrain became too steep. By 2230 on July 5 the fire covered approximately 50 acres.
The fire continued to burn actively during the night, spreading as a surface fire downhill toward the West Drainage through the pinyon-juniper and grass and laterally to the north through an area covered with Gambel oak. The fire maintained a more continuous flaming front and was much more active through the night of July 5 and early morning of July 6 than it had been the previous night (Bell 1994). We attribute the increased fire activity to lower relative humidities than occurred on previous nights.
Between 0530 and 0600 on July 6, eleven BLM and Forest Service firefighters started hiking up the East Drainage to the fire. At 0800 the BLM/ USFS crew constructed H-2, a helispot located about 1/4 mile north of H-1. Around 0845 Incident Commander Blanco and Jumper-in-Charge Mackey discussed strategy and tactics for the day. They decided to improve the fireline between H-1 and H-2 (using the BLM and Forest Service firefighters) and to start building a fireline along the fire’s west flank (using the smokejumpers). At approximately 0930 they took a reconnaissance flight in the helicopter assigned to the fire. In a later interview the pilot, Dick Good, said that on this flight he noticed smoke low in the West Drainage (Good 1996). The fire perimeter map developed after the reconnaissance flight indicated that the fire covered about 127 acres (fig. 19). At 1027 eight more smokejumpers parachuted to the Drop Zone north of H-2. At 1130 the combined jumper crews started downhill direct fireline construction on the West Flank.
Flareups, small reburns, and slopovers occurred throughout the fire late in the morning. The figure 20 photograph, taken from Interstate 70, shows smoke from fire activity northwest of H-1 on the West Flank and also southwest of H-1 in the area near the Double Draws. At approximately 1135 a flareup on the West Flank Fireline ran approximately 120 feet up the slope to the top of the Main Ridge in a narrow, about 5 foot wide, run (South Canyon Report). This run prompted discussion to pull out of the West Flank fireline and ignited a spot fire that the firefighters on the Main Ridge worked to extinguish. Bucket drops of water from the helicopter cooled the flareup, and work on the fireline resumed. In response to a flareup in a tree located south of the Spur Ridge at about 1300, smokejumpers working near the Spur Ridge retreated 480 feet back along the fireline to a point near the Tree (South Canyon Report; Petrilli 1996). A water drop from the helicopter cooled the flareup, and the firefighters returned to the area where the fireline crossed the Spur Ridge. Smokejumper Rhoades cut down the tree that became the Stump reference point, and the firefighters resumed building the fireline.
Between 1230 and 1300, the helicopter ferried 10 of the Prineville Hotshots, including Hotshot Superintendent Shepard, from Canyon Creek Estates to H-2. Around 1330 nine of the hotshots, led by Squad Leader Kelso, were assigned to reinforce the smokejumpers constructing the West Flank Fireline. Shepard remained on the Main Ridge. The remaining 10 Prineville Hotshots remained at the helibase at Canyon Creek Estates. They noted an overcast sky and gusty winds around 1400. Between 1400 and 1430 Hotshot Foreman Scholz radioed Shepard three times to report gusty, erratic winds at the helibase and increased smoke low on the fire’s west side. During one of the calls, Shepard responded that winds had increased on the Main Ridge.
Lunch Spot—Between 1400 and 1430 many of the hotshots and smokejumpers working on the West Flank Fireline stopped for lunch on a small knoll midway up the Lunch Spot Ridge (thus the name Lunch Spot). Jumpers Thrash and Roth remained on the West Flank Fireline. At approximately 1445 Smokejumper Longanecker left to scout an area south of the Lunch Spot Ridge. He hiked southwest from the Lunch Spot into the Double Draws (South Canyon Report). At about 1510 Longanecker requested by radio that some smokejumpers come down and start building line around a hotspot that had flared up (South Canyon Report). The smokejumpers stated that they felt some concern about building new line when the fire was still active along the newly completed West Flank Fireline to the north. A few of the smokejumpers moved a short distance south and east into the northeast side of the Double Draws (see Petrilli Photo Point and Longanecker position in fig. 8). Longanecker requested and received a water drop on the hotspot. Witness statements indicate that as the winds increased so did the fire activity in the underburned pinyon-juniper south of the Lunch Spot Ridge and along the Main Ridge (South Canyon Report).
Main Ridge—Around 1515 the helicopter ferried the remaining 10 Prineville Hotshots from Canyon Creek Estates to H-2. They were assigned to widen the fireline on the Main Ridge between H-2 and the Zero Point. West winds between H-2 and the top of the West Flank Fireline were strong enough that when the firefighters working on the Main Ridge tossed brush into the air, the wind carried it over the east side of the ridge (South Canyon Report). In contrast, about 300 feet away, some of the group stopped for a break near the Zero Point and noted that the winds were light, estimated to be less than 5 miles per hour (South Canyon Report). Fire activity in the underburned oak on the west side of the Main Ridge consisted of low intensity flaming and smoldering in the leaves and debris on the ground under the oak canopy with some torching of individual trees.
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