DIOXINS IN DENVER (RMA)

[Lenny Siegel <lsiegel@igc.org>]

DIOXINS IN DENVER

The Rocky Mountain Arsenal, the Army's former chemical weapons manufacturing 
facility north of 
Denver, is well into the process of becoming a wildlife refuge - at 
least, according to government policy. However, that's not the way the 
animals see it. Many raptors, rodents, and other species have been 
dying of unknown causes.
 To determine likely causes, the State of Colorado contracted 
for the analysis of "fortuitous specimens" and soil samples at the 
Arsenal. It found not only significant concentrations of pesticides 
such as aldrin, dieldrin, and eldrin, but measurable quantities of 
extremely toxic, persistent, and bioaccumulative dioxins and furans. 
This is the first time that anyone has looked for dioxins and furans at 
the Arsenal, yet their discovery came somewhat as a surprise. Though 
the quantities were low, they represent levels that could cause death 
or at least limit reproduction in birds. It is too soon to tell, but 
since the Army's on-based record of decision does not address these 
contaminants, confirmation of the problem could force the re-opening of 
the Arsenal's $2 billion remedial action program.
 The State's contractor, Eco Logic (of Ann Arbor, Michigan), 
analyzed four soil samples and seven "fortuitous" animal specimens, 
ranging from a great horned owl that died by electrocution to a big 
brown bat to three deer mice.
 Eco Logic found aldrin, dieldrin, and endrin in all the soil 
samples, with combined concentrations ranging from 830 to 2,160 parts 
per million. Soil dioxin concentrations approached 10 parts per 
billion, but consisted principally of the less toxic forms of dioxin, 
such as octachlorodioxin.
 The same pesticides were found in the animal samples, along 
with DDT and other contaminants. In one of the great horned owls, 
researchers found 6.9 parts per million of PCBs (polychlorinated 
biphenyls) in the adipose (fatty) tissue and .99 parts per million in 
the liver. In another owl, adipose PCBs reached 27.68 parts per million.
 Of the seven specimens, at least three had total toxic 
equivalents of dioxins and furans - that is, total concentrations 
weighted by known toxicity of the specific compounds - above 200 parts 
per trillion, considered enough to cause adverse impacts.
 [Waylard R. Swain, Ph.D., "Results of a Survey of Selected 
Fortuitous Specimens and Soil Samples from the Rocky Mountain Arsenal 
for Trace Organic Contaminants, Arsenic and Mercury," Final Report, Eco 
Logic International, February 12, 1996.]
 The Eco Logic reports doesn't delve into potential sources of 
the contamination, but those may include products or byproducts of 
chemical weapons by the Army or agricultural chemicals by Shell, 
herbicides used to control weeds, and the products of the combustion of 
wastes. The animal specimens, however, were taken and frozen before the 
construction and operation of the submerged quenched incinerator for 
"Basin F" liquid wastes.
 
Lenny Siegel