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LeTourneau, Inc. Steel Group Scrap Radioactive Source (Cesium
137) Melt Down July 20,2006LTI - Steel Products Scrap Radioactive
Source (Cesium 137) Melt Down July 20, 2006LeTourneau Inc. Steel
Group Scrap Radioactive Source (Cesium 137) Melt Down July 20,
2006
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• On July 21, 2006 Horsehead Industries (our K061 baghouse dust
recycler) inTennessee notified Bill Stuckey that our most recent
truck shipment, July 20th
, on a four point radiation check, was showing “HOT” and was
returning theshipment to us.
• After notification from Horsehead, the entire Steel Mill was
surveyed for highradiation readings with hand held Geiger
Counters.
• Every area from the Finishing End through the Rolling Mill to
the Pouring Aislein the Melt Shop was normal background.
• The baghouse area including the fluidizer and silo registered
a high level ofradioactivity count on the Geiger Counter. The area
was caution taped off tokeep personnel out while continuing to run
the Melt Shop (a decision that laterproved to be beneficial in
decreasing the clean-up time).
• The “HOT” truck returned and was isolated far away from any
personnel onSaturday, July 22nd. It too, was radioactive surveyed
with the hand held GeigerCounter and found to be high in activity
count.
• On Monday, July 24th, a certified health physicist was
contacted and hired todo a survey of the truck and baghouse to
determine what we had.
• He surveyed the area early Tuesday, July 25th, and determined
LTI - SteelProducts had melted a Cesium 137 source approximately 1
curie in size.
• On July 25th the State of Texas Health Department was
contacted.• July 25th : all Steel Mill employees were told of the
findings and the clean-up to
follow.• On July 26th a contractor was hired to perform the
clean-up.
FACTS LEADING TO DISCOVERY
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FACTS ABOUT RADIOACTIVE SOURCES
• Of the three isotope sources involved in scrap melt downs
(cesium 137, cobalt 60, americium 241)cesium 137 volatilizes at low
melting temperatures going to the dust collection system. Cobalt
willdiffuse into the steel and dust. Americium 241 will be in the
slag, steel, and dust.
• Based on the readings taken, the size of the melted source was
determined to be from ameasuring device found in the oil/ gas field
drilling sector.(drill head measuring; density gauges;fluid flow
monitors; level control; etc.)
• These devices are regulated under the General Licensed Devices
(GLD) by the United StatesNuclear Regulatory Commission per Title
10 CFR Part 31.5. The GLD does not require the user toobtain a
license nor perform routine testing, but does allow the user to
install, relocate, and usewithout a licensed person. When the
devices are no longer in service they “should” be returned tothe
manufacturer or a licensed waste broker for “proper” disposal.
• There are over 320 sources in the State of Texas and 4,200
sources in the United States whosewhereabouts are not known
today.
• The fine for improper disposal - $18,000 approximately. The
cost to proper dispose - $2,000depending on the size of the
source.
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THE CLEAN-UP
• August 2nd met with the State of Texas Health Department to
discuss workplan (remediation of clean-up) and receive their
approval.
• August 2 – 5: mobilized trailers for decon/ offices/
lab/canteen/ etc.
• August 4: clean-up personnel mobilized.
• August 5th & 6th: Clean-up personnel training for hazmet/
confined space/safety/ etc.
• August 6th: At 9 P.M. melt shop shut down to cool
baghouse.
• August 7th: At 3 A.M. clean-up began.
• August 13th: At 8:05 P.M. the melt shop returned to
production.
• There are several areas in the melt shop which required
additional time toclean-up due to the cesium being fixed on the
surfaces.
• The clean-up still continues with decon of the silo,
fluidizer, vac trucks, andfinal disposal of the baghouse dust.
• Analyze of dust will be taken for several weeks until the
first truckload can beshipped to EAF dust recycler again.
• Of the 15 known clean-ups for radioactive melts, this was the
FASTEST (6days, 23 hours, and 5 minutes) and the least cost.
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FUTURE
• Before restarting the Melt Shop on August 13th at 8:05 P.M.,
the entire scrap yard wassurveyed using a SAM 9 detector unit. The
area was clean.
• On July 26th four different manufacturers of hand held
spectrometers were contacted viaemail for quotes.
• On July 31st two “identiFINDER” isotope identifier units were
purchased from ThermoElectron Corporation.
• On July 26th, Ludlum Measurement, Inc., from Sweetwater, TX.
was contacted to supply atruck/ scale scanning unit. Initial unit
was to have 6 scanners.
• On August 3rd, a redundant system for the scrap bucket scale
was requested from Ludlum.• On August 11th, personnel from Ludlum
visited LeTourneau, Inc. to finalize plans and meet
with our IT Group. It was decided to increase the truck/
railroad system to six scanners. Aquote for the six scanner system
plus the scrap bucket system was sent August 15th. Thesystem will
be installed in four weeks.
• All trucks going to the melt area whether directly received or
reloaded from the yard arebeing surveyed currently with Geiger
Counters and later surveyed by the spectrometers andscanners.
• All three additions will give LTI the best system available.•
Our redundant system decreases the likelihood of a source getting
through due to the
handling and repositioning of a potential source.• Again, our
posture is to maintain based on 320 plus sources in Texas and 4,200
sources in
the United States whose whereabouts is unknown, that there is a
source waiting to comein. Our determination is to stop it before it
is melted.
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Slide Number 1Slide Number 2FACTS ABOUT RADIOACTIVE SOURCESTHE
CLEAN-UPFUTURESlide Number 6Slide Number 7Slide Number 8Slide
Number 9Slide Number 10Slide Number 11Slide Number 12