Discussion Points – 2010 R6 Smoke Intrusions
Overview: September 2010 was an active month for prescribed burning on the NFs in Oregon and
Washington, as a relatively cool and wet summer set up nearly ideal fuels conditions for broadcast
burning in September and October. At the end of September, a broad upper ridge extended across
Oregon and Washington, with a surface thermal trough lying just west of the coast. The result was
warm, dry, and still air with light surface and transport winds – good for prescribed burning, but not
good for smoke dispersal. Smoke from three prescribed burns in different parts of Oregon settled at
night, causing smoke intrusions in 4 areas defined as Smoke Sensitive Receptor Areas (SSRAs) – Bend,
Enterprise, La Grande, and Lakeview, OR.
FLAs were conducted by all three units involved in these burns, in order to improve future performance
based on the experiences of 2010. The following is intended as a summary of the common results of
these FLAs – the full FLAs are available from the units involved.
o
The roles of the burn bosses and the burning agency in smoke management-related tasks are
not universally understood. It is clear that it is the responsibility of the burn boss to register burns,
communicate with smoke management immediately prior to the burn, obtain smoke management
instructions, etc. The responsibility of the state smoke management meteorologists is to understand
the timing and location of a proposed burn, provide forecasts and instructions in a timely manner, etc.
Good relationships between state smoke managers and the burn boss goes beyond merely calling and
documenting discussions.
o
A spot weather forecast comes from the National Weather Service, and is a required part of the
prescribed burn implementation, but is not a substitute for a smoke management forecast.
o
An intrusion is any entrance of smoke at ground level to an SSRA (Oregon), or below 2,000 feet
over a Designated Area (Washington). While an intrusion does not typically result in smoke of
sufficient concentration and duration to result in an exceedance of National Ambient Air Quality
Standards (NAAQS), it is the goal of the state smoke management program to avoid any intrusions.
o
The 2010 intrusions occurred either from multiple burns occurring on the same unit or from
multiple day burns. Burn bosses tend to get busy with the day-to-day work of running a prescribed
burn, and often are pressed for time to monitor smoke impacts to downwind receptors, spend time
and energy communicating with the public, county commissioners, media, and other agencies. A
prescribed fire manager can be used to take up some of these “off-site” duties, and with good
communication with the burn boss, can be a valuable part of the success of the project.
o
Multi-day, landscape-level burns will continue to be an important part of our forest restoration
program. However, smoke management and weather forecasts are less certain beyond the first 24
hours, and conditions can often change once the multi-day burn has started. When possible, burn
bosses should have plans for suspending burns if conditions deteriorate (using roads and other breaks,
for example) – recognizing that this is not always possible, especially in large blocks of unroaded
country.
o
Often smoke management instructions in Oregon recommend against burning units that will
smolder significantly overnight within a certain distance from SSRAs. Multi-day, landscape level burns
will, by design, burn through the night. We (regional staff) will be working with smoke forecasters on
better ways of handling multi-day burns in forecasts and instructions.
o
Being proactive is always better – communicating with line officers about the forecasts,
instructions, and risks, communicating with smoke forecasters early and often, communicating with the
public, etc. If/when things go wrong, the communication need is greater – don’t wait for air regulators
(DEQ or Ecology) or smoke management meterologists to call you, make the call yourself.