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Duncan Canyon Burnout Operation Briefing - Tahoe National Forest The purpose of the burnout is to prevent the fire from extending into North Fork drainage. Attempts to use direct attack in the Duncan creek drainage have been unsuccessful, and have raised significant concerns for firefighter safety due to the extremely steep terrain and heavy fuels. The burnout is expected to occur over the course of three or four nights, with holding actions planned for the late morning and afternoon hours. Firefighter safety: The primary objective of the burnout operation is fire suppression, with natural resource protection as a secondary objective. This strategy has the greatest chance of containing the Star Fire while maximizing firefighter safety and resource protection. The conditions in the bottom of Duncan Creek have been described as extremely hazardous by seven of the hotshot crews who have attempted to build lines in the canyon. Given the conditions in the canyon, there is no opportunity to establish effective safety zones. In addition, it is likely that the canyon will be smoked in, preventing air support from accessing the canyon and helping firefighters at times when they are likely to need it the most. The incident management team will not jeopardize firefighter safety. Overview of Star Fire History: The fire started on Saturday, August 25, at 0641 hours. The cause of the fire is under investigation. It grew from 10 acres to 3,000 by Sunday and doubled in size on Monday. California Incident Team 1 assumed command of the fire on August 28 and has staged the fire camp and incident Command post at French Meadows Reservoir. Firefighter and public safety is paramount in this fire where old growth forest, wildlife values, and structures are potentially threatened. While there is no immediate fire threat, smoke generated by this fire has been very heavy in Truckee, Reno, Lake Tahoe and other communities surrounding the fire. The fire is currently at 11,940 acres and 45% contained. Total cost to date fighting the Star Fire is more than $7,700,000. Control methods near the flame front (direct attack) were employed in Duncan Canyon for three consecutive days. Fire crews were able to make little headway due to the steep terrain. They became increasingly concerned about becoming trapped beneath rolling debris and falling snags. Trees, both standing green and torched, have been falling frequently throughout the fire area, often falling without a sound until they reach the ground. Current tactics in Duncan Canyon have been focused on preventing spot-overs across the creek, using air support such as water drops from heavy helicopters. The fire currently borders Duncan Creek on a three mile front. These efforts have been successful to date, but are not sustainable and will not lead to containment or control of the fire. Impacts of Burning Out: Introducing a slow moving, low intensity backfiring into Duncan Canyon drainage is expected to result in lesser impacts than if the fire is permitted to spot across the creek and make a run on its own uphill. The burnout will occur in the evening and night hours when temperatures are lower, relative humidity is higher, and winds tend to be calmer. Ignition will be done in a manner to minimize the risk of burning debris rolling downhill and starting a new uphill head fire. Protecting old growth trees: Where the fire has made uncontrollable, high-intensity runs, resource specialists expect significant soil loss. The heat generated in some areas has sterilized the soil and removed all organic material. A less intense backfiring fire will provide the greatest degree of protection to the soil. Protecting wildlife: Fire personnel and nearby communities have observed a great deal of wildlife movement, initiated by the dry conditions occurring unusually early in the season, then exacerbated by loss of habitat in the fire area. More trees would be left unburned during a planned burnout period. This situation ill give many wildlife species opportunities to seek escape routes and cover. Due to the anticipated decrease in mortality, there will be less habitat destruction, and affected habitat will recover more rapidly. Total acres burned: If the burnout s successful, it will reduce the total amount of forest burned. Without this type of action, it is likely that the fire would triple, at a minimum. Curtailing smoke: Communities around Lake Tahoe, Truckee, Reno, and others have been subjected to heavy smoke for the last week, prompting health advisories, causing changes in school sports schedules and venues, and many other impacts. The burnout operation is designed to bring this fire event to a close in the most expeditious and safe manner possible, allowing affected communities to resume normal activities. Reducing costs: The cost of the fire has reached over $7 million to date, in part due to the need for heavy air support in slowing the spread of the fire in extremely steep terrain. Although the burnout operation itself will require additional air support to ensure it proceeds at the planned rate, if successful it will bring the suppression to an end much more quickly. Emphasizing firefighter safety: The heat and terrain are taking their toll on the firefighters, and the incident has experienced a number of injuries. Most of them, thankfully, have been relatively minor. However, each additional day increases the probability of a more serious injury, especially in the terrain of Duncan Canyon and North Fork. Burnout Strategy and Tactics Strategy: The firing strategy will take advantage of evening and nighttime conditions to create a low-intensity backing fire from an established firebreak. Due to the unevenness of the terrain and breaks in the fuels, it is likely that fingers could develop which would burn under and then create their own headfires. To avoid this, hand firing may be supplemented with an aerial ignition device. The aerial tactic will be used to achieve an even rate of burning downslope along the burnout line. Creating a mosaic of unburned areas will be acceptable, especially if they are located well away from the perimeter of the burnout area and risk of spot-overs is low should they kindle later. In most locations, creating a band of burned fuel a minimum of 500 feet away from the control line will be sufficient to reduce the probability of spot-overs. Areas well away from the perimeter, such as the bottom of the canyon adjacent to Duncan Creek, will not be ignited directly. If the backing fire goes out in those areas, it will not be re-ignited. Tactics: Test firing will start near the area of Division CC in section 12 near DP 15 and Division D near DP 12. Test firing is critical to ensure that conditions are as planned before committing to the entire operation. If conditions are not favorable, air support will work quickly to prevent spread of the test fire. If conditions are favorable, the operation will proceed to burn into Duncan Canyon simultaneously on the evening of September 2. Hand-thrown ignition devices may be used to increase depth to the required 500 feet by daylight. Most hand firing will take place at night to take advantage of downslope winds. Hand firing lines to the west of DP 12 will take pace only if determined necessary by the Branch Director and when conditions allow for safe completion and minimal impact to resources. This section will probably be fired on the evening of September 2. The Ignition Specialist may utilize aerial ignition to extend burning depth and interior burning if needed. Interior firing will be used to keep the backing fire even on the slope and to initiate backfiring down interior ridges and to remove a head fire threat to structures in the burn area. Weather: Weather data will be collected from both the top and bottom of the canyon twice daily and as needed to monitor temperature, humidity, wind speed and direction, and other factors. At the bottom of the canyon, weather will be collected by a remote weather station. In an operation of this type, it is critical to closely monitor the behavior of up- and down-slope winds to predict their effect on burnout operations. For example, in Division A ignition should be completed one hour before winds make their usual nighttime shift from up-canyon to down-canyon. Weather monitoring allows the incident meteorologist to predict when that shift is likely to occur. Summary: The minimum impact burnout operation in Duncan Canyon is designed to most effectively balance firefighter safety with resource protection because:
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