TRANSURANIUM ELEMENTS AROUND THE ROCKY FLATS PLANT .
NX
page 2
to prevent spread of the plutonium bearing soil and
four water sample wells for confirmation that no downwaxrd migration was occuring were completed in November
1969.
After a fire on May 11, 1969 at Rocky Flats, studies were
conducted by the Colorado Committee on Environmental
Information (CCEI) and by the Health and Safety Laboratory
(HASL) of the USAEC, concerning the possible release of
plutonium from the fire.
These investigations detected
measurable quantities of plutonium in the soil around
the Rocky Flats Plant.
Concentrations of plutonium in
soil at Rocky Flats have also been estimated by the Colorado
Department of Health
(CDH),
Rockwell International, °
Jefferson County Health Department, and private housing
developers.
In general, measurements made by the different
groups have shown similar
surface plutonium levels.
(but not identical)
results for
The HASL data indicate that releases from past operations
have
amounted to about
11
curies of plutonium,
approx-
imately 99% of which was leakage from drums in the storage
area.
The epicenter of the isopleth map shows that
the contamination can not be attributed to the May 1969
fire but is due to resuspension and redistribution of
contaminated soil from the oil drum storage area.
During the removal of the corroded drums and the sub-
sequent covering operations, some radioactive material
was resuspended and distributed by wind action to the
east of the storage area.
The HASL estimate of the total
amount of plutonium dispersed by the oil leaks
(11 Ci)
is higher than the estimate of the total amount of plu-
tonium available to be dispersed.
The potential amount
was estimated by Rocky Flats on the basis that the 5000
gallons of oil that leaked from the drums contained 86
grams
(5.3 Ci) of plutonium.
estimates,
accurate.
To reduce conflicting
the HASL data is considered to be the most
The HASL data suggest that of the 11 Ci released, 8.6 Ci
are on site.
Of the amount off site, the HASL data indicate that about 1.5 Ci are included in the area above
0.003 mCi/m2 (3mCi/km2) which extends to about 5 miles
‘