Kansas City Plant

Special Exposure Cohort Petit

Evaluation Report

Grady Calhoun, CHP

Supervisory Health Scientist

NIOSH/DCAS

January 28, 2014

Kansas City, Missouri
Overview

 Received March 12, 2013 Petitioner requested class definition

• All Bannister Federal Complex employees who w

the Bannister Federal Complex from 1949 to pres

 Qualified July 1, 2013

• Basis – Radiation exposures and doses potentiall

by members of the proposed class were not mon

either through personal or area monitoring
Overview – continued

 NIOSH‐designated Evaluation Report (ER) start date 

with the start of AEC operations

 Examined 160 claims with employment 1994 or later 

coincide with KCP’s implementation of 10 CFR 835 todetermine evaluation period end date

 NIOSH found no apparent and potentially inadequat

monitored exposures for post‐1993
NIOSH‐evaluated class

All employees who worked in any area Kansas City Plant in Kansas City, MO, frJanuary 1, 1949 through December 31, 
Background

 Main Manufacturing Building main stru

 About 2.7 million square feet of contiguou

 Houses the primary KCP manufacturing op
Background – continued

 From the start principal operation to m

non‐nuclear components of nuclear we

• Machining and fabrication of metals and plastics, 

microelectronics, and electrical and mechanical a

 Currently makes about 85% of the non‐

components for the U.S. atomic stockpi
Background – continued

 Natural uranium work

• Machined uranium slugs, handled uranium 

and ingots from February 1951 to Decemb

• Performed this work in the Main Manufac

Building (Department 49X)

• Total of 313,070 lbs machined into slugs

• Capacity to produce 1,000 slugs per day
Background – continued

 Natural uranium work (cont.)

• Inspected and assembled uranium compon

from May 1950 to February 1955 in the M

Manufacturing Building (Department 3A)
Background – continued

 Depleted uranium (DU) work

• April 1958 to about 1971

• Machined and inspected DU products in Departm

(about 12,000 ft2 of the Main Manufacturing Buil

• Main source of radiological exposure associated w

machining items that contained DU oxide

• Program using DU oxide ended in 1972
Background – continued

 Magnesium Thorium alloy (Mg‐Th) wo

• Supplied by DOW ‐ HK‐31 alloy ~3% Thoriu• May 1, 1957 to April 5, 1979 ‐ machined an

fabricated classified items with Mg‐Th allo

areas of the Main Manufacturing Building

(Department 20 and the Model Shop)

• Strict operational controls to prevent airbo

generation
Background – continued

 Thorium oxide (ThO2) powder work

• Reviewed one document that stated from July 23

July, 1959 was handled in the plant.

• Several personal communications with site exper

review of radiological source inventories found th

handling was limited to small‐scale laboratory an

preparation of solutions used in analytical proced
Incidents

Erbium Tritide (September 30, 1987) Worker removed the cover of a W80 Data An

and noticed that the interior not decontaminrequired, immediately replaced cover

 Surveys performed of the analyzer and the w

 Contamination only detected on the inside of 

cover at 986 dpm/100 cm2
Incidents – continued

Erbium Tritide (cont.) Analyzer returned to Sandia National Laborat

decontamination

 Urinalysis performed for the worker who rem

cover; results indicated no detectable activity 

tritium as erbium tritide (sol class M from ICR

 This was an isolated, one time incident
Incidents – continued

Promethium‐147 ‐February 10, 1989 100% beta‐emitting, EMax 224.7 keV, half‐life 

years

 Failure of the integrity of one of these source

resulted in a spread of contamination to muareas inside and outside of facility

 97 personnel internally monitored, no intern

exposures

 Workers’ homes inspected, one needed

decontaminated
Sources of Available Informa

 Site Profile TBD‐6000, used to model internal 

for the natural uranium machining operation

 KCP Site Profile ORAUT‐TKBS‐0031 (2006), us

describe DU internal doses and external dose

 Reviewed 1,645 NIOSH Site Research Databa

documents

 Conducted 19 interviews

 Standard data searches conducted
Prior Dose Reconstruction

NIOSH DCAS Claims Tracking System

Information available as of November 22, 2013

 KCP claims submitted for dose reconstruction 672

 Cases submitted for energy employees who

worked during the period under evaluation(1/1/49 ‐ 12/31/93) 665

 Number of dose reconstructions completed

for energy employees who worked during the

period under evaluation 608

 Cases for which internal dosimetry records

were obtained 35

 Claims for which external dosimetry records

were obtained 103
Personal Monitoring Data

 Internal Monitoring Data

• Routine bioassay data (urinalysis) ava

for the DU work 1959 ‐ 1971

• Air sample data:

• 1952 dust analysis

• 1958 ‐ 1971 Gross alpha Fixed‐filter air

monitoring in the Main Manufacturing 

general area
Personal Monitoring Data – co

 Internal Monitoring Data (cont.) 

• Air sample data: 

• Magnesium Thorium (Mg-Th) Operations • In 1970, KCP evaluated all of their Mg-Th 

machining operations in the Model Shop 

• The evaluation validated that KCP mainta

airborne levels in the breathing-zone for lived activity at background, and short-livactivity at <3.22E-9 μCi/ml (gross alpha) 
Personal Monitoring Data – co

 External Monitoring Data

 Access to 13,846 external dosimetry records 

include monitoring data for deep dose, shalloextremity dose (rings) and neutron dose, for 1950 ‐ 1993

 KCP participated in DOE LAP performance tes

using Landauer‐provided services starting in 

1992
Area Monitoring Data

 Recently obtained copies of

• 1959 ‐ 1969 and 1990 ‐ 1993 routine conta

and radiation surveys

• Contamination survey data and volumetr

sampling data from 1984‐1986 Decontamand Decommission (D&D) activities
Evaluated Period Potentia

Radiation Exposures

 Internal sources of exposure

• Inhalation and ingestion of uranium and thorium b

at KCP

• Residual airborne radioactive contaminants may h

present at low levels after the operations ceased

 External sources of exposure

• Photon / beta exposure from the uranium and tho

material, and small amounts of surface contamina

was present after operations ceased.

• Sources of neutron radiation involved Karman Mod

pulsed‐neutron generators and 239PuBe sources. Th

presence of neutron‐emitting sources occurred aft
Evaluated Period Potentia

Radiation Exposures

 External sources of exposure

• Isotopic (beta, gamma‐ray) sources that ar

typically used in manufacturing quality con

procedures to monitor fabrication process

• Industrial radiation generating devices (X‐

electron accelerators)
Feasibility of Dose Reconstruc

 Available monitoring records, process

descriptions, and source‐term data are

adequate to complete DRs with sufficien

accuracy for evaluated worker class
Feasibility Approach – continu

 Natural Uranium Operations

• NIOSH is satisfied that TBD‐6000 can 

used to estimate KCP exposures whe

dosimetry is not available
Feasibility Approach – continu

 Natural Uranium Post Operations Period

• Internal exposures after natural U operatio

and before DU internal monitoring started

• March 1, 1955 to August 11, 1959• Use the maximum measured gross alpha a

during this post operations period

• Use TBD‐6000 methodology to bound air

concentrations for worker classes with less

exposure potential than the machine oper
Feasibility Approach – continu

 Magnesium Thorium Operations

• KCP specified engineered control levels at 

beginning of operations in 1957 at 9E‐11 μ

• October of 1959 KCP lowered limit to 3E‐1

• Performed (Gross α) fixed‐filter air‐monito

the Main Manufacturing Building (GA) dur

13 years of these operations

• Maintained operations at 2.85E‐12 μCi/ml (Av

<8.55E‐11 μCi/ml (Maximum)
Feasibility Approach – continu

 Magnesium Thorium Operations (cont.)

• The initial KCP limit of 9E‐11 μCi/ml for Th232 w

equate to ~27 mg/m3 total‐dust air‐concentra

well‐tolerated for a full shift (W. R. Van Pelt, B

Steel study)

• In 1970, KCP performed worksite, breathing‐z

sampling (Gross α) and validated that their pr

does not generate airborne radioactivity

• This validation was performed prior to KCP’s c

of fixed filter air‐monitoring in 1971
Feasibility Approach – continu

 Magnesium Thorium Operations (cont.)

• To bound internal exposures for machine operators, NIOSH 

• initial engineered limit of 9E‐11 μCi/ml and apply it in a const

from 5/1/57 through 10/31/59

• lowered engineered limit of 3E‐11 μCi/ml and apply it in a con

from 11/1/59 through 4/30/79

• Ingestion doses derived with OCAS‐TIB‐009• Thoron exposure: use highest 1970 short‐lived sample, 3.2E

yields, 5.1 WLM/yr

• TBD‐6000 methodology used to bound air concentrations fo

workers with less exposure potential or that spent less time 

machining area than the machine operators
Feasibility Approach – continu

 Bounding thorium intakes after Mg-Th operatio

ceased and before facility D&D 

• Assume air concentration at the end of 

operations was the lower limit of 3E-11 μ(66.6 dpm/m3) 

• Use deposition, re-suspension and depl

models to assign intakes. 

• Ingestion doses derived using OCAS‐TIB‐
Feasibility Approach – continu

 Bounding thorium intakes after Mg‐Th operations 

and before facility D&D

 Thoron dose basis for this period will start the peri

5.1 WLM/yr and will use the same depletion rate (

4/yr) to determine the exposure for each year of th

period

 TBD‐6000 methodology used to bound air concent

for classes of workers with less exposure potential spent less time in the machining area than the mac

operators
Feasibility Approach – continu

 Bounding uranium intakes after M

operations ceased and before faciD&D 

 Maximum measured surface contamin

survey taken during DU machiningoperations will be used to model a sta

point air concentration for this post‐

operational period
Feasibility Approach – continu

 Bounding uranium intakes after Mg‐Th

operations ceased and before facility D

• Applying a re‐suspension factor of 1E‐5/m, yields 

concentration of 0.6 dpm/m3 (0.27 pCi/ m3) for t

the post operations period on May 31, 1984

• A depletion rate will be applied to the initial air

concentration to determine the remaining activit

available for inhalation and ingestion for machinoperators during each year of this post operation
Feasibility Approach – continu

 Bounding uranium intakes after Mg‐Th

operations cease and before facility D&

 TBD‐6000 methodology used to bou

concentrations for classes of workers 

less exposure potential or that spent 

time in the machining area than themachine operators
Feasibility Approach – continu

 D&D Activities 6/1/84 – 9/3/86

• Rockwell employees were monitored• Barriers set‐up around work area and cont

air monitoring performed outside perimet

• Monitored for U238 at 1E‐12 μCi/ml control 

• Assume KCP employees are exposed at the

perimeter air‐concentration during this pe
Summary

Summary of Feasibility 

(January 1, 1949 through December 31, 1993) 

Source of Exposure Feasible Not Feasi

External X 

Internal X