The soil cap of the 93-acre Basin F wastepile at the Rocky Arsenal National
Wildlife Refuge was removed Monday, and crews are prepared to deal with the
spread of odor in surrounding communities.
It's been almost 20 years since the arsenal and Tri-County Health tried
to clean up the site. They, along with residents and commuters largely north
and west of the arsenal along state Highway 2 and East 96th Avenue, were
surprised by the offensive odor that permeated from the 93-acre site, all
uncapped at the same time. This time, crews will open only one acre at a
time and will be prepared to shut down the Basin F worksite and triple-line
wastepile within minutes to keep the odors from causing a stink.
With work having started Monday, arsenal officials are asking the public
to report odors that may signal a repeat of the previous clean-up disaster.
Basin F was built in 1956 to store the liquid waste from the Army's creation
of mustard gas and lewisite, both blistering agents, following the attacks
on Pearl Harbor. The Army also created the nerve agent sarin gas at the arsenal,
which was intended to disable the enemy, although death sometimes resulted,
according to Rocky Mountain Arsenal Remediation Venture Office Program Manager
Charles Sharmann.
In 1952, Shell Oil Co. leased the facility to create herbicides and pesticides.
Sharmann said when production ceased in the early 1980s, the 93-acre waste
lagoon capable of holding 243 million gallons of liquid contaminants was to
evaporate.
It remains a Superfund site, and when it came time to clean up Basin F in
1988 and 1989, the weather and moisture were not taken into consideration,
Sharmann said, when the entire 93 acres were uncovered and readied for transport
to a triple-lined landfill one mile away on the arsenal. The result of the
added moisture and the fluctuating temperatures sent the odors into nearby
neighborhoods.
Bruce Wilson, interim deputy director of Tri-County Health, said much was
learned from the mistakes made during the first attempt at cleaning up the
basin in the late 1980s. A weather station was built just to the north of
the basin and the triple-lined landfill. Information from that station will
tell work crews if they should even attempt to open up the basin or landfill
for work on a particular day.
Sharmann said with just one acre being opened at a time, if bad weather
crops up once work started, the site could be shut down within minutes with
a plastic tarp or odor-suppressing foam.
Wilson said it will be the role of Tri-County Health to monitor odor on
and off site. Their crews also will investigate reports of odors within an
hour of a complaint. Wind direction and weather conditions will give crews
some idea as to whether an odor originates from Basin F.
As work is done on-site, Sharmann said crews wearing protective gear and
self-contained air devices will use heavy equipment to scoop up the waste,
load it onto trucks that won't leave the site and haul it one mile to the
triple-lined landfill.
The permanent landfill will include multiple layers of strong plastic capable
of allowing water to run off into collection areas ready to treatment, plus
a 3-foot layer of nearly insoluble clay near the surface of the waste. The
entire landfill, Sharmann said, would then be covered with a thick layer
of soil. To visitors, it will look just like a large hill covered with tall
grass. It would take someone a lot of work to reach the buried waste. The
entire landfill area is designed to keep contaminants from seeping into regional
aquifers.
Odor hotline
A 24-hour odor response hotline through Tri-County Health Department
to report possible odors stemming from the Basin F wastepile clean up is
303-286-8032.
Contact news editor Linda Tharp at ltharp@metrowestnewspapers.com or 303-659-2522,
ext. 217.