Noxious weeds overtake Flats
DOE considers prescribed burns to combat risk of grasslands fire
By TERJE LANGELAND
Colorado Daily Staff Writer
To most people, the name "Rocky Flats" probably doesnít conjure up visions
of wild plants and animals in a pristine, natural setting. Yet in reality,
more than 90 percent of the Rocky Flats site consists of grasslands,
shrublands, wetlands and riparian areas.
The 5,800-acre "buffer zone" that surrounds the 400-acre former nuclear
weapons plant has been relatively undisturbed by development for almost
half a century, since Rocky Flats was built in 1952. As a result, the
buffer zone is home to grassland habitats that have nearly disappeared
elsewhere along the Front Range. The zoneís unit of xeric grassland
prairie, for example, is thought to be the largest of its kind in North
But the buffer zone hasnít just been untouched by development. For the
last 25 years it has also been nearly untouched by a natural force that
ecologists consider vital to healthy grasslands: fire. Now, the Department
of Energy wants to reintroduce fire as a way to manage the vegetation in
the area, a proposal that has some observers concerned but has drawn
support from others.
Prescribed burns are identified as one of several preferred approaches in
a draft vegetation management plan developed by the DOE. Additional
approaches ó most of which are already being used on the site ó include
herbicide application, biological controls, mowing and manual removal.
According to Patricia Powell, a physical chemist at Rocky Flats, the
prescribed burns would be used to remove 25 years of buildup of dead
vegetation in the buffer zone. Not only would this reduce the danger of an
accidental fire raging out of control; it would also help native plants
that are being choked by noxious weeds, she said. "It allows the moisture
to get to the ground and allows sunlight to reach the seedlings," Powell
Since 1990, the vegetation management plan states, the buffer zone has
been invaded by several types of noxious weeds that threaten the native
plants, including diffuse knapweed, Canada thistle, muck thistle and
"The Department of Energy is required to take action to control the spread
of these weeds and reduce their populations on-site in order to maintain
habitat quality and comply with several state and federal weed control
statutes," the vegetation management plan states.
But Paula Elofson-Gardine of the Environmental Information Network, a
Rocky Flats watchdog organization, called the burning proposal "a really
bad idea." As the DOEís own draft plan points out, plants have been shown
to absorb plutonium from soil. Elofson-Gardine said burning plants in the
buffer zone would release plutonium into the air as particulate matter,
which could then be inhaled by people downwind. "This is a hazard for
local residents," Elofson-Gardine said. "This stuff is really bad when
itís inhaled. Thatís the worst pathway of exposure."
In 1991, tests by the state health department showed elevated levels of
plutonium in the ashes from a haystack fire that took place just off the
site, across from the plantís east entrance, Elofson-Gardine said. Rather
than burning, the DOE should consider letting livestock eat the
vegetation, or removing it manually, she said.
But Powell said removing dead vegetation from a 5,800-acre area by hand
would be a "daunting" task. And using livestock simply wouldnít work
because animals prefer to eat fresh plants, she said. "Livestock wouldnít
eat dead and downed vegetation," Powell said.
Moreover, Susan Jones-Hard of the state health departmentís laboratory and
radiation services department said the 1991 tests were actually conducted
to measure radiation from dirt that firefighters used to put out the
haystack fire. While the dirt was found to be contaminated, the health
department concluded that "there was no significant increased risk to the
firefighters," Jones-Hard said.
Powell also said the DOE had conducted a radiation assessment of a
hypothetical prescribed burn in one of the buffer zoneís most contaminated
areas, and found that it would not cause significant releases of
radionuclides. Burns would not be conducted in certain parts of the buffer
zone that are known to be highly contaminated, and burns would only take
place under "favorable weather conditions," including low wind speeds,
according to the plan.
Elofson-Gardine, however, said she didnít believe the DOE knows where all
the contaminated areas are. She cited documents which she said indicated
that Rocky Flats workers used to secretly dump radioactive waste in the
Rocky Flats spokesman Pat Etchart responded that contamination in the
buffer zone has been thoroughly mapped through sampling. Before conducting
any burns, the DOE would obtain a burn permit from Jefferson County and
notify neighbors. Crews would also monitor the air during burns and have
outside officials participating and observing.
The DOE has discussed the plan with neighboring landowners, including the
city of Boulder and Boulder County, whose open-space areas abut the site.
Cindy Owsley, an ecologist with the Boulder County open space department,
said she supported using prescribed burns at Rocky Flats. "I can
understand why there is a concern to have burning on that site," Owsley
said. However, fires will occur one way or another, and itís better to do
it in a prescribed fashion than to wait for an accidental, out-of-control
fire, she said. "Itís not if a burn would happen," Owsley said. "Itís when
a burn would happen. ... Itís going to happen eventually."
The DOE is seeking public comments on its draft vegetation management plan
through April 19. If the plan receives final approval, burns could take
place late this spring or in the fall. The plan can be viewed at
www.rfets.gov. Copies can also be ordered by calling Mariane Anderson at