DRAFT - DRAFT DRAFT

particle sampling releases. The cratering Plowshare tests, where the test was
designed to produce a throw-out of earth, have been designated as ‘test-crater’
releases. Releases from surface tests have been categorized as ‘test/surface’.
Those surface and near-surface tests, that were non-nuclear tests designed to
determine the extent of debris scattering, have been defined as ‘test/plutonium
dispersal’ releases.”

A “controlled” release was “a planned, filtered, release frequently performed to
reduce airbome radiation levels in the working environment” predominantly from ~
tunnels, although this type of release “also occurred from shaft tests”.
“’Drillback’ releases occurred during postshot drilling operations to recover
samples; these releases were either filtered or unfiltered. After drillback
operations were completed, a ‘cementback’ occurred where the drill hole was
sealed with a plug and cemented to the surface.” Releases also occurred during
“cementback” operations.

“Gas sampling’ releases occurred during gas sampling operations, either before
or after any postshot drilling operations commenced.”

“Late-time seepage’ releases occurred when noble gases have leaked from test
sites after all operations in the area have ceased. These releases “could exist from
a few hours to even weeks after all other operations in the area have ceased.” (1)

Other activities cited that brought radioactive isotopes to the surface from the explosion
site include:

“Cable pull” defined as “Recovery of a cable placed near a nuclear explosion.
The cable ran to the surface and was pulled free shortly after zero time. The
debris captured on the bottom end of the cable was analyzed to assess device
performance.”

“Catcher pull” defined as “Recovery of a debris catcher, placed near a nuclear
explosive, by pulling on the attached cable and thus returning the catcher to the
ground surface. This operation is usually accomplished within minutes to hours
of zero time.” (1)

Construction Worker Radiation Exposures at the Nevada Test Site:

Construction workers at the Nevada Test Site could reasonably have been expected to be
exposed to radioactivity in the following situations:

In the construction of roads, buildings, and related infrastructure through areas of
the site contaminated with residual, postshot contamination;

In the drilling of vertical shafts used for the placement of test nuclear explosive
devices;

In the underground mining of tunnels (long horizontal drifts mined into a
mountain or mesa) and test chambers in close proximity to areas where previous
test shots were detonated;

During postshot drilling operations to recover samples. “Drillback” releases often
occurred at the drilling rig and lasted for periods ranging from hours to days,
likely contaminating the drilling rig and associated equipment that construction
workers would have to move to another site and re-use.


Did you ever have
personal items or
clothing taken from
you because they had
become contaminated

by radiation? n=2733
Yes 631 23.09
No 2102 76.91
If yes, how many
times? n=586
1 277 47.27 6.13 17.63
2 119 20.31
3 64 10.92
4 25 4.27
5 20 3.41
6 14 2.39
7 3 0.51
8 2 0.34
9 1 0.17
10 2t 3.58
[ 12 2 0.34
15 7 1.19
16 4 0.17
20 4 0.68
23 4 0.17
25 1 0.17
30 2 0.34
40 2 0.34
50 1 0.17
99 19 3.24
Do you think that you
might have been
contaminated by
radiation during any
of the following
events?
Rainier Test (Sept. 19,
1957) n=2723
Yes 107 3.93
No 2616 96.07
Operation Nougat
Tests (Sept. 15, 1961 I
to June 30, 1962) n=2705
[ Yes 236 8.72



No 89 47.85
Number of Post-Shot LOS Pipe Entries in Shafts n=258
i) 75 29.07
1-10 126 48.84
11-20 14 5.43
21-30 11 4.26
31-40 2 0.78
>40 30 11.63
“Other” Work in Shafts n=380
Performed 108 28.42
Present 48 12.63
Neither 224 58.95
[Ever Worked on Drillhote Event n=2739
[ Yes 1444 52.72
No_ 1295 47.28
Number of Drillhole Events Worked On: n=1396
0 18 1.29
1-10 654 46.85
11-20 217 15.54
21-30 153 10.96
31-40 73 §.23
>40 281 20.13
Number of Drillhole Events Involved with Drillback n=1355
0 473 34.91
1-10 443 32.69
11-20 131 9.67
21-30 89 6.57
31-40 46 3.39
>40 173 12.77
‘Assembled Rack n=387
Yes 94 24.29
No 293 75,71
Installed / Modified / Machined Cone on the Cage _ n=390
Yes 29 7.44
No 361 92.56



Count with
Gamma Count with
Dose record] Average Beta Dose
in Gamma Standard | Maximum | record in Average Standard | Maximum
Dosimetry Dose Deviation Dose Dosimetry | Beta Dose | Deviation Dose
Shaft Database (mrem) (mrem) (mrem) Database (mrem) (mrem) (mrem)
Shaft-yes 1073 2581 24580 148 629 6195
Shaft-no 352 1486 36210 22 147 2905
Shaft reentry
yes 1590 3442 24580 176 597 3485
Shaft reentry:
no 415 1244 412375 47 399 6135
Shaft reentry:
present 960 2625 15985 207 748 4460



Frequency of Worker Reported Contractors (n=399

|

REECO 368 92.23
EG&G 29 7.27
LLNL 4 1.00
LANL 3 0.75

SNL 1 0.25
H&N 9 2.26
F&S 4 1.00
|Wackenhut 6 1.50
DOE 5 1.25
DOD 5 1.25
Other 93 23.21



One factor that could partially account for these large differences is that Sandia, Los
Alamos and Lawrence Livermore sites had individuals involved in work on the NTS
site and the database we were reviewing included NTS/REECO workers only.

> The 1963 Operation Storax report (REECO 1964) indicated that 17 persons had a
dose exceeding the 5 rem per year operational guideline. The maximum
individual dose was 5,925 mrem. The NTPR database for the year 1962 indicated
1 individual greater than 5 rem, 34 individuals greater than 4 rem, and 89
individuals greater than 3 rem with a maximum individual dose of 5125 mrem
and for the year 1963 the NTPR database indicated only 2 individuals with doses
greater than 3 rem and a maximum dose of 3325 mrem. Again, this H&S report
could be discussing more than just NTS personnel.

> A March 1983 report (REECO 1983) regarding the change from film badges to
TLDs mentions that only approximately 100 individuals at the NTS are
potentially exposed to neutrons and require neutron monitoring. It may be that
this is a very conservative estimate however; it is interesting to note that
according to the 19631983 database there is only one neutron dose record greater
than zero. The missed neutron dose, at least for a select small population, may be
something that requires more investigation.

> The 1986-1987 Musketeer H&S report (REECO 1988) indicates that 66,112
dosimeters were issued for 25,997 REECO/ESD personnel. The dosemast
database includes only 13,474 records (quarterly dosimeter records).

> Operation Hardtrack Report (REECO 1958) indicated that there was some alpha
contamination in the U-12f tunnel. Preliminary review of the ‘dead’ bioassay
database indicates 12 individuals received some kind of alpha testing (possibly
nasal wipe) with all results being recorded as zero. This may be an example of
potential missed plutonium intakes. Further assessment would be necessary.

> One of the case files reviewed contained several pages from a logbook from the
U12B 1962 event. One entry in the log stated as follows: “Each shift will obtain
a 24 hour sample (urine) from one person, preferably someone who has spent time
in the main drift”. This seems to indicate the importance of cross-checking event
logs when performing an individual dose reconstruction.

> We reviewed an event database (area_arc_sort.dbf), which included event name,
year, individual’s names, and organization. We did a query of this database
against the 19631983 dosimetry database and determined that there were 2833
unique last names that were RECCO employees and of those unique last names,
only 1313 (46%) were found in the 19631983 database. It should be noted that
this query likely overestimated the number of individuals for whom data existed
in the database since we only used Jast name (no unique id available) and we did
not look at the year for which dosimetry data was available compared to the year
the last name was listed in the event database. Review of this type of information,
event logs or databases, will probably be even more important for the case of
internal dose especially if all workers in certain events were not monitored (see
previous item).

> A specific event from the event database (area_arc_sort.dbf) was reviewed to
determine the number of workers who were monitored for plutonium exposures.


Operating Engineers: Cumm Gamma Dose vs.
Years Worked (first worked 1950s)

4500 -
4000

1-5 yrs 6-10 yrs 10-20 yrs >20 yrs
Years Worked



Carpenters : Cumm Gamma Dose vs. Years
Worked (first worked 1950s)

3500
3000
2500
2000
1500
1000

500

0 '

<1 6-10 yrs 10-20 >20yrs
yrs

Years Worked

& Gamma Dose (mrem) |



Table 1

Count with Count with
Gamma Dose | Average Beta Dose
Count in Work record in Gamma Standard | Maximum record in Average | Standard | Maximum
History Dosimetry Dose Deviation Dose Dosimetry |Beta Dose] Deviation Dose
Job Classification | Questionnaire Database ({mrem) (mrem) _(mrem) Database {mrem) (mrem) (mrem)_
Operating Engineer 642 545, 780 41822 14791 515 51 284 4200
Other Union 158 81 994 3192 17752 75 141 635 4134
Plumber / Pipefitter 145 129 125 528 4405 126 5 25 224
Sheet Metal 37 35 42 118 565 33 1 5 30
Teamsters 222 178 213 728 7635 172. 10 43 355
Painters 23 10 1405 2559 7635 10 100 118 355,
Carpenters 166 135 427 1375 8800 119 13 95 1000
Laborers 630 513 1226 2705 17752 481 203 752 6195
IBEW. 437 341 483 41956 24580 323 59 345 4134
Ironworkers 138 110 816 3560 36210 4104 18 75 585
Non-Union 445 208 916 2328 15810 198 164 712 6135



Laborers: Cumm Gamma Dose vs. Years Worked
(first worked 1970s)

300
250 -
200 +
150
100 +
50 +

0 i i za sail oe ese 2b
1-5 yrs 6-10 yrs 10-20 yrs >20 yrs
Years Worked



Ironworkers: Cumm Gamma Dose vs. Years
Worked (first worked 1970s)

fm Seriest

<1 1-Syrs 6-10 yrs 10-20yrs >20 yrs
Years Worked



regular records for 1964, annual summary record for 1965-1971, and regular records for 1972-
1991. External dosimetry database indicates regular records for 1951, annual summary records
for 1959, annual summary records for 1963-1971 (except 1964), and regular records for 1972-
1991. Database recorded doses are consistent with hard copy records. Hard copy records and
database indicate no bioassay data.

Case 17:

Individual indicated that he worked from 1958 — 1993. Full case file indicated regular records
from 1958 through 1993 except for 1965, 1969 and 1971 which included annual summary data
only. External dosimetry database indicates regular records for 1958, annual summary data for
1959-1971, and regular records from 1986 through 1992. Database recorded doses were
consistent with hard copy records. Hard copy records indicate tritium sampling in 1961-1962.
Database records indicate 14 tritium samples from 1961-1962. Hard copy records also indicate a
thyroid dose of 34 rad assigned in 1963. There were records in the hard copy records for the
iodine exposure but there were no related data in the database. Finally, the database and hard
copy records both indicate 1 alpha nasal smear taken in 1962 with no dose assigned. The
calculated tritium doses were reviewed using the same assumptions as the NTS staff used and
using CINDY version 1.4 with ICRP 30 tritium model and doses consistent with the reported
doses were obtained..

Case 18:

Individual indicated that he worked from 1964 ~ 1995. Full case file indicated regular records
from 1964 through 1995 except for 1964, 1968-1971 which included only annual summary data.
External dosimetry database indicates no records for 1964-1983 and regular records for 1986-
1992. Hard copy records indicate tritium sampling during 1965-1967, 1972, 1974, 1976-1978,
and 1980-1987. Tritium doses were assigned in 1967, 1974 and 1981. Database records indicate
33 tritium samples from 1976-1985. The calculated tritium doses were reviewed using the same
assumptions as the NTS staff used and using CINDY version 1.4 with ICRP 30 tritium model
and doses consistent with the reported doses were obtained..

Case 19:

Individual indicated that he worked from 1961-1989. Full case file indicated annual summary
record for 1960, regular records for 1961-1963, annual summary record for 1964-1971, and
regular records from 1972 - 1992. Case file includes one result for 1992 but no data for 1990-
1991 (these years appear to be outside the self-reported work end date). External dosimetry
database indicates annual summary records for 1960-1971 and regular records from 1972-1989
and 1 record in 1992. Hard copy records indicate 3 tritium samples for 1961-1962. Database
records indicate 2 tritium samples from 1962-1963; none in 1961 (which was the only hard copy
record greater than detectable). Dose was assigned in 1961. Hard copy records and database
records indicate 3 tritium samples in 1981 with no dose assigned.


Rock Dust 366 87.35 2.40 0.97
Diese! Smoke 396 92.34 2.73 0.94
Oil Fumes 343 82.45 2.31 1,02
Welding Fumes 395 92.07 2.33 0.94
[Asbestos 258 70.49 1.84 0.86
Solvents 363 87.26 2.08 0.86
Epoxy 311 76.98 2.06 0.92
Sulfa-set 224 58.64 1.84 0.86
Grout 256 65.14 1.94 0.90
Solvents - Skin 325 77.20 2.02 0.89
Epoxy - Skin 270 66.18 1.83 0.79
Sulfa-set - Skin 191 49.61 1.57 0.76
Grout - Skin 207 52.41 1.57 0.77
Beryllium 81 32.66 1.93 0.83
lronworkers
Loud Noise 132 96.35 3.27 0.87
Vibration 116 86.57 2.75 1.08
Shotcrete 71 61.21 2.06 1.04
Rock Dust 112 85.50 2.38 1.01
Diese! Smoke 119 88.81 2.72 0.96
Oil Fumes 108 83.72 2.42 1.09
Welding Fumes 136 99.27 3.56 0.73
Asbestos 93 76.23 2.48 1.06
Solvents 103 79.23 2.22 1.04
Epoxy 82 66.67 2.00 0.94
Sulfa-set 69 56.10 1.83 0.87
Grout 75 59.06 1.99 0.91
Solvents - Skin 102 76.69 1.94 0.89
Epoxy - Skin 76 69.38 1.79 0.87
Sulfa-set - Skin 62 50.41 1.61 0.73
Grout - Skin 66 52.38 1.67 0.79
Beryllium 28 41.29 1.86 0.93
Plumbers / Pipefitters
Loud Noise 138 98.57 3.17 0.89
Vibration 123 88.49 2.79 1.04
Shotcrete 99 76.15 2.31 0.98
Rock Dust 118 86.13 2.65 1.02
Diesel Smoke 133 96.38 2.78 1.08
Oil Fumes 110 85.94 2.32 1.12
Welding Fumes. 137 98.56 3.43 0.80
Asbestos 112 85.50 2.34 1.05
Solvents 126 92.65 2.55 4.02
Epoxy 107 80.45 2.09 0.97
Sulfa-set 91 70.00 1.88 0.96
Grout 98 73.13 2.02 1.02
Solvents - Skin 130 94.20 2.41 1.02
Epoxy - Skin 97 71.85 1.78 0.93



ton Guest

i Near

Baneberry Test
(December 18, 1970) . n=2716
Yes 483 17.78
No 2233 82.22
Misty Rain Test (N
Tunnel, April 6, 1985) n=2718
Yes 380 13.98
No 2338 86.02
Mighty Oak Test (T
|Tunnel, April 10, 1986) n=2722
Yes 369 13.56
No 2353 86.44
Other tests or
accidental releases n=2592
Yes 834 32.18
No 1758 67.82
Did you ever have
body counts taken to
check for radiation
exposure? n=828
Yes 265 32
No 344 41.55
Don't Know 219 26.45
Did you ever have
urine or fecal tests
taken to check for
radiation exposure? n=828
Yes 148 17.87
No 459 55.43
Don't Know 221 26.69
Were you ever told
that you had "burned
out" or exceeded the
quarterly or yearly
limits for radiation? n=2742
Yes 309 11.27
[ No 2433 88.73



Non-Union: Cumm Gamma Dose vs. Years
Worked (first worked 1980s)

160
140
120 |
100

|TM@ Series1

<1 1-Syrs 6-10 yrs 10-20 yrs >20 yrs
Years Worked



3.2 Former Worker Cohort

The cohort being considered in this report consists of the individuals who participated in
the BU medical surveillance program from September 1998 through March 21, 2003.

The screened cohort consists of 2753 individuals with a mean age of 62 and an average of
approximately 12 years of NTS work experience. The cohort consists of construction
trades workers and is focused on underground and excavation workers. Each participant
in the medical surveillance program completed a comprehensive work history
questionnaire which asked very specific tasks about test site work activities related to
above ground testing and tunnel tests. A copy of the latest version of this questionnaire is
provided as attachment A.

3.3 Construction Worker Radiation Exposures at the Nevada Test Site:

Construction workers at the Nevada Test Site may have been exposed to radioactivity in
the following situations:

e Inthe construction of roads, buildings, and related infrastructure through areas of
the site contaminated with residual, post-shot contamination;

e In the drilling of vertical shafts used for the placement of test nuclear explosive
devices;

e Inthe underground mining of tunnels (long horizontal drifts mined into a
mountain or mesa) and test chambers in close proximity to areas where previous
test shots were detonated;

¢ During post-shot drilling operations to recover samples. “Drillback” releases
often occurred at the drilling rig and lasted for periods ranging from hours to
days, likely contaminating the drilling rig and associated equipment that
construction workers would have to move to another site and re-use.

e And during shaft plugging where the drill hole was plugged and cemented to the
surface (“cementback”).

4.0___ Description of BU medical surveillance questionnaire

2753 individuals who participated in the medical surveillance program completed the
work history questionnaire. The questionnaire was self administered and then reviewed
by project staff. The individuals screened were members the following trade unions:
Laborers (630), IBEW (437), Operating Engineers (642), Ironworkers (138),
Plumbers/Pipefitters (145), Carpenters (166), Sheetmetal (37), Teamsters (222), Painters
(23), Guards - IGAN (128), Other Union (158), and Non-Union (445).

The questionnaire also requests information on reported exposures (dust, beryllium,
solvents, noise, and other hazards), tasks that workers performed (e.g., tunnel work and
type of work conducted during tunnel work), the area(s) where they worked, and specific
questions related to potential radiation exposure (some of these questions were only
recently added to the questionnaire and therefore there was not a great deal of data for
some of these questions). The work questions were developed following interviews and
focus groups with former and current NTS workers, and NTS industrial hygienists and


Operating Engineers: Cumm Gamma Dose vs.
Years Worked (first worked 1970s)

1-5 yrs 6-10 yrs 10-20 yrs >20 yrs
Years Worked



Operating Engineers: Cumm Gamma Dose vs.
Years Worked (first worked 1960s)

5000 ~

4000
3000
2000

1000 -

<4 1-Syrs 6-10 yrs 10-20 yrs >20 yrs

Years Worked

M@ Series1



Other Unions: Cumm Gamma Dose vs. Years
Worked (first worked 1950s)

6000
5000 4
4000

3000
2000 4
1000 |

0
1-5 yrs

6-10 yrs 10-20 yrs

Years Worked

>20 yrs



Performed 154 24.02
Present 186 29.02
Neither 301 46.96
Construction in Shafts n=645
Perfomed 254 39.38
Present 169 26.2
Neither 222 34.42
Pre-Shot LOS Pipe Work in Shafts n=643
Performed 180 27.99
Present 137 21.34
Neither 326 50.7
Pre-Shot LOS Pipe - Installed / Modified Flanges in Shafts n=188
Yes 57 30.32
No 131 69.68
IPre-Shot LOS Pipe - Worked In / Around A-Box in Shafts n=107
Yes 70 65.42
No. 37 34.58
Pre-Shot LOS Pipe - Installed / Modified Cone at A-Box in
Shafts n=105
Yes 19 18.1
No 86 81.9
Worked at Test Chambers in Shafts n=107
Yes 73 68.22
No. 34 31.78
Pre-Shot LOS Pipe - Grind / Machine / Modify Materials in
[Test Chambers in Shafts n=106
Yes 30 28.3
No 76 717
Pre-Shot LOS Pipe - Worked in Instrument Alcoves in
Shafts n=108
Yes 80 74.07
No 28 25.93
Pre-Shot LOS Pipe - Grind / Machine / Modify Materials in
Instrument Alcoves in Shafts n=106
Yes 33 31.13



DRAFT DRAFT DRAFT

e And during shaft plugging where the drill hole was plugged and cemented to the
surface (“cementback”).

References:

1. DOE publication “Radiological Effluents Released from U.S. Continental Tests

1961 through 1992” (DOE/NV-317 (Rev. 1) UC-702).

DOE publication “United States Nuclear Tests July 1945 through September
1992”, (DOE/NV—209 REV 15, December 2000),

2.


Loud Noise 138 90.20 2.98 1.12
Vibration 117 76.97 2.79 1.14
Shotcrete 63 46.67 2.25 1.09
Rock Dust 103 69.59 2.64 1.10
Diesel Smoke 120 78.43 2.65 1.10
Oil Fumes 104 70.27 2.51 1.11
Welding Fumes 100 65.79 2.26 1.07
Asbestos 81 60.00 2.35 1.09
Solvents 100 68.49 2.64 1.11
Epoxy 66 47.83 217 4,00
Sulfa-set 60 44.12 2.00 0.96
Grout 76 53.15 2.22 1.01
Solvents - Skin 84 58.74 2.51 1.10
Epoxy - Skin 47 35.07 2.06 0.99
Sulfa-set - Skin 44 32.84 1.77 0.99
Grout - Skin 49 36.03 2.06 1.03
Beryllium 31 31.00 2.42 1.15
Non-union
Loud Noise 410 93.61 2.64 1.04
Vibration 349 80.23 2.40 1.07
Shotcrete 242 59.02 1.99 9.94
Rock Dust 315 74.64 2.21 0.99
Diesel Smoke 379 86.93 2.51 0.98
Oil Fumes 336 78.14 2.24 1.00
Welding Fumes 343 79.58 2.08 0.98
Asbestos 217 56.81 1.72 0.89
Solvents 325 76.29 2.07 0.93
Epoxy 272 65.23 1.89 0.87
Sulfa-set 207 51.62 1.82 0.86
Grout 269 64.35 2.05 0.94
Solvents - Skin 272 63.40 1.93 0.93
Epoxy - Skin 211 50.24 1.71 0.87
Sulfa-set - Skin 155 37.99 1.61 0.85
Grout - Skin 197 47.93 1.80 0.93
Beryllium 123 43.01 2.01 0.90



Renod

Loud Noise 609
Vibration 599
Shotcrete 473
Rock Dust 573
Diese] Smoke 589
Oil Fumes 527
Welding Fumes 536
Asbestos 359
Solvents 475
Epoxy 452
Sulfa-set 456
Grout 514
Solvents - Skin 437
Epoxy - Skin 402
Sulfa-set - Skin 422
Grout - Skin 470
Beryllium 112
Operating Engineers
Loud Noise 636 99.38 3.54 0.74
Vibration 609 96.21 | 3.27 0.94
Shotcrete 345 59.79 iz 2.26 1.03
Rock Dust 511 86.36 2.78 1.01
Diesel Smoke 617 97.01 3.36 0.82
L Oil Fumes 555 89.95 2.96 1.04
{___Welding Fumes 551 87.60 2.59 1.08
Asbestos 337 59.75 2.07 1.06
Solvents §25 83.73 2.59 1.10
Epoxy 352 59.36 1.86 0.95
Sulfa-set 289 49.40 1.94 0.98
Grout 388 63.82 2.16 1.00
Solvents - Skin 501 80.42 2.61 1.09
Epoxy - Skin 294 49.41 1.73 0.91
Sulfa-set - Skin 257 43.56 1.83 0.97
Grout - Skin 333 §5.22 1.96 0.95
Beryllium 75 21.93 2.01 0.98
IBEW
Loud Noise A417 95.86 2.82 0.99
L Vibration 365 85.28 2.50 0.99
| Shotcrete 265 68.30 2.18 0.97



No 73 68.87
Support in Shafts n=644
Performed 228 35.4
Present 169 26.24
Neither 247 38.35
Button-Up in Shafts =644.
Performed 189 29.35
_ Present 124 19.25
Neither 331 51.4
Re-entry in Shafts n=645
Performed 159 24.65
Present 112 17.36
Neither 374 57,98
Post-Shot LOS Pipe Work in Shafts n=632
Performed 168 26.58
Present 86 13.61
Neither 378 59.81
Post-Shot LOS Pipe - Worked in Test Chambers in Shafts . n=188
Yes 104 $5.32
No 84 44.68
IPost-Shot LOS Pipe - Worked in Test Alcoves in Shafts n=102
Yes 62 60.78
No 40 39.22
Post-Shot LOS Pipe - Support Users in Test Chambers /
instrument Alcoves in Shafts n=103
Yes 67 65.05
No 36 34.95
Post-Shot LOS Pipe - Cut / Disassembled LOS Pipe in
Shafts n=185
Yes 61 32.97
No 124 67.03
IPost-Shot LOS Pipe - Disposed of LOS Pipe / Contents in
Shafts n=186
Yes 97 $2.15



9.0 References

Betzel, RE, Radioactivity associated with underground nuclear explosions, University of
California Lawrence Radiation Laboratory, June, 1959, UCRL-5623.

Bowen, SM, Finnegan, DL, Thompson, JL, Miller, CM, Baca, PL, Olivas, LF, Geoffrion,
CG, Smith, DL, Goishi, W, Esser, BK, Meadows, JW, Namboodiri, N, and Wild, JF,
Nevada Test Site Radionuclide Inventory, 1951-1992, Los Alamos National Laboratory,
September, 2001, LA-13859-MS.

DOE, 1994, United States Nuclear Tests July 1945 through September 1992, DOE/NV-
209 (Rev.14)

DOE, 1996, Radiological Effluents Released from U.S. Continental Tests 1961 through
1992, DOE/NV-317 (Rev. 1) UC-702.

DOE, 2000, United States Nuclear Tests July 1945 through September 1992, DOE/NV—
209 REV 15.

REECO 1957, 1957 REECO H&S Report Excerpt, page 236.

REECO 1958, Operation Hardtack Phase II On-Site Rad-Safe Support Report, REECO,
RRS-58-3.

RFECO 1964, Operation Storax On-Site Radiological Safety Report, REECO, RRS-64-
17, NVO-162-14.

REECO 1988, Operation Musketeer Onsite Radiological Safety Report for Announced
Nuclear Tests (October 1986 through September 1987), RRS-88-19, DOE/NV/10327-37.

REECO 1983, Friedrichs, RE and Brady, WJ, A proposal for conversion from film to
Thermoluminescent Dosimeters at the Nevada Test Site, RRS-85-11.

Smith, DK, Finnegan, DL, and Bowen, SM, An Inventory of long-lived radionuclides
residual from underground nuclear testing at the Nevada Test Site, 1951-1992, Journal of
Environmental Radioactivity, Volume 67, pages 35-51, 2003.

Skrable, KW and French, CS, Evaluation of Protection, Bioassay, and Dose Assessment
Programs for Internal Radiation Exposures at the Nevada Test Site Particularly as Related
to Three Exposure Situations, Prepared for Reynolds Electrical and Engineering Co., Inc.,
September, 1995.


Count with Count with
Gamma Dose Average Beta Dose
record in Gamma Standard Maximum record in Average Standard
Dosimetry Dose Deviation Dose Dosimetry |Beta Dose] Deviation | Maximum
Tunnel Database (mrem) (mrem) (mrem) Database (mrem) {mrem) _}Dose (mrem)}
Yes 789 2294 36210 96 488 6195
No 226 754 7416 10 58 850
Number
) 203 666 4150 21 152 4415
1 639 2081 36210 58 357 6135
1 to 10 970 2361 12480 154 627 5745
11 to 20 1378 2710 14791 205 573 2936
21 to 30 1635 2968 1240 290 1179 6195
31 to 40 2778 4856 24580 392 1082 4356
>40
Reentry
Yes 1309 3113 36210 199 707 6195
No 374 1290 47752 10 58 1020
Present 700 1889 10060 4126 598 4460
Number
0 217 704 5510 8 51 1020
1 928 2547 36210 4103. 480 6135
1 to 10 1372 2856 12865 220 750 5745
11 to 20 1808 3365 14791 378 776 2935
21 to 30 2409 2559 7081 1055 2266 6195
31 to 40 3230 5367 24580 345 978 4134

>40



Operating Engineers: Cumm Gamma Dose vs.
Years Worked (first worked 1980s)

Te A
m Series1 |

<1 1-Syrs 6-10 yrs 10-20 yrs >20 yrs
Years Worked



Ironworkers : Cumm Gamma Dose vs. Years
Worked (first worked 1950s)

10000 -
8000 4

| | Seriest |

<4 1-5 yrs 6-10 yrs 10-20 yrs >20 yrs

Years Worked



OT RPE

interesting to note that 872 individuals reported that they had been decontaminated at
least once and 1871 individuals reported that they had not been decontaminated. The
average lifetime cumulative gamma dose for those who indicated they had been
decontaminated for radioactive material contamination was approximately 1400 mrem as
compared to approximately 300 mrem for those who hadn’t gone through any
decontamination.

Table 5 shows the lifetime cumulative dose for individuals who reported doing any
tunnel work during their career (questionnaire variable a8) and the second part of table 5
shows the relationship of cumulative dose as a function of the number of tunnels
(variable a8a). The third section of this table shows the cumulative dose as a function of
the tunnel re-entry task (variable a8d5). The fourth section of the table shows the number
of tunnel events where they did re-entry work (worked in tunnel after the test was
performed) (variable a8b The average cumulative dose trended as would be expected
(increasing with increasing number of events and with increasing number of re-entries).
When controlling for years worked and decade starting work, preliminary analysis
suggests no clear relationship between the numbers of tunnel events that individuals
reported working in with their recorded external gamma dose. We suspect that a recall
bias may impact this response leading to an attenuation of an effect.

Table 6 shows the lifetime cumulative dose for individuals who reported being involved
in work during any above ground testing (variable a7) and the second part of the table
indicates cumulative doses as a function of the number of tests during which they worked
(variable a7a). The third part of this table shows the cumulative dose as a function of the
number of times an individual performed nuclear event cleanup (variable a7b). Again,
this preliminary analysis was not controlled for total number of years worked or for
decade hired. The average cumulative dose trended as would be expected (increasing
with increasing number of events and generally with the number of event responses).

The average cumulative gamma dose calculated for those who reported being involved in
an above ground test was approximately 1900 mrem as compared to approximately 120
mrem for those who were not involved. When controlling for years worked and decade
starting work, preliminary analysis suggests no relationship between the number of
atmospheric tests that individuals reported working in with their recorded lifetime
cumulative gamma dose. . However, comparing the cumulative gamma dose for the
1950s compared to the number of above ground tests that individuals reported
participating in, the average cumulative gamma dose increased with increasing number of
above ground tests from 952 mrem for 1 event (n=121) to 3,565 mrem for 21-30 events
(n=44).

Table 7 shows the lifetime cumulative dose for individuals who reported doing any shaft
work during their career and the second part of table 5 shows the relationship of
cumulative dose as a function of the shaft re-entry task. This preliminary analysis is not
controlled for total number of years worked. Again the average cumulative dose trended
as would be expected (higher cumulative averages for individuals who were involved in
shaft work compared with those who were not and higher cumulative dose for those who
performed re-entry work in the shafts).



Pre-Shot LOS Pipe - Grind { Machine { Modify Materials in
[Test Chambers in Tunnels n=249
Yes 86 34.54
No 163 65.46
Pre-Shot LOS Pipe - Worked in Instrument Alcoves in
(Tunnels n=250
Yes 205 82
No 45 18
Pre-Shot LOS Pipe - Grind / Machine / Modify Materials in
Instrument Alcoves in Tunnels n=251
Yes 92 36.65
No 159 63.35
[Support in Tunnels n=2004
Performed 858 42.81
Present 308 15.37
Neither 838 41.82
Button-Up in Tunnels n=2004
Performed 830 41.42
Present 194 9.68
Neither 980 48.9
Re-entry in Tunnels n=2009
Performed 798 39.72
Present 189 9.44
Neither | 1022 50.87
IPost-Shot LOS Pipe Work in Tunnels n=1125
Performed 366 32.53
Present 135 12
Neither 624 55.47
Post-Shot LOS Pipe - Worked in Test Chambers in Tunnels n=401
Yes 254 63.34
No. 147 36.66
Post-Shot LOS Pipe - Worked in Test Alcoves in Tunnels n=227
|__Yes 162 71.37
_| No 65 28.63 |



IBEW: Cumm Gamma Dose vs. Years Worked
(first worked 1980s)

i |mSeriest |

<1 1-Syrs 6-10 yrs 10-20 yrs >20 yrs
Years Worked



Non-Union: Cumm Gamma Dose vs. Years
Worked (first worked 1960s)

1-5 yrs 6-10 yrs 10-20 yrs >20 yrs
Years Worked



Non-Union: Cumm Gamma Dose vs. Years
Worked (first worked 1970s)

1-5 yrs 6-10 yrs 10-20 yrs >20 yrs

Years Worked



Numberof Workers - All Trades

800

700

600 =

500

400

300

200

<1 month

1-6 months

Total Time Worked at NTS
n=2746

7 - 12 month:

1-5 years
Years of NTS Work

6 - 10 years

11-20 years

> 20 years

@BSeries1


Plumbers/Pipefitters: Cumm Gamma Dose vs.
Years Worked (first worked 1980s)

400 5

350

300 +
250 +

200

150 4

100
50

0 i

<1

1-5 yrs

6-10 yrs 10-20 yrs >20 yrs
Years Worked

@ Series



Dosemast 1986-1993 74,817 records (TLD data)

The following databases were used to review internal dose:

Dead.mdb 1955-1963 32,072 records; 3257 unique last names
midbio.mdb 1964-1987 19,980 records; 2000 unique SSNs
1984 1984 220 records

1985 1985 29 records

1986 1986 41 records

Dosemast 1986-1993 74,817 records; 36 results greater than zero

The NTPR database contains 45,308 records for the time period from 1945 through 1962.
This database was comprised primarily of deep dose data (film badge data with detection
limit of 30 mrem). The data primarily consists of annual summary data for the period
1959-1962 and weekly, monthly or quarterly data for the period 1952-1958. Only about
500 records are dated prior to 1952. 22,630 records (50%) had greater than zero deep
dose recorded with 1422 (3.1%) in excess of 1 rem. Beta dose monitoring was not
prevalent during this time period with beta dose recorded for only 220 records in the
database and with only 4 records greater than zero.

The 19631983 database contains 140,769 records (film badge data). This database
primarily contains gamma dose data, beta dose data, and neutron dose data. There are
139,577 gamma dose records with only 4647 (3.3%) greater than zero. There are
129,035 beta dose records with only 864 (0.6%) greater than zero, There are 129,019
neutron dose records with only 1 record greater than zero. This database contains some
annual summary data and some monthly or quarterly results.

The 1984 database contains 34,728 records including gamma dose results (34,009 records
with 96 records (3.7%) greater than zero), beta dose results (34,009 records with 28
records (0.1%) greater than zero), body part dose results (648 records with 464 records
greater than zero), neutron dose results (34,009 records with none greater than zero), and
intemal dose results (220 records with 3 (1.3%) results greater than zero).

The 1985 database contains 36,920 records including gamma dose results (35,710 records
with 132 records (0.3%) greater than zero), beta dose results (35,710 records with 85
records (0.2%) greater than zero), body part dose results (567 records with 438 records
(77%) greater than zero), neutron dose results (35,710 records with none greater than
zero), and internal dose results (29 records with 8 results (28%) greater than zero).

The 1986 database contains 34,387 records including gamma dose results (33,601 records
with 252 records (0.7%) greater than zero), beta dose results (33,601 records with 71
records (0.2%) greater than zero), body part dose results (477 records with 273 records
(57%) greater than zero), neutron dose results (33,601 records with none greater than
zero), and internal dose results (41 records with 41 results (100%) greater than zero).


health physicists. The questionnaire has been modified and updated based on new
information and feedback from these groups. . Appendix A (Summary Of Worker
Demographics and Work History Information On Radiation Hazards) includes a
summary of the findings in the questionnaire.

Medical questions are also included. Subjects are asked about a history of cancer,
radiation treatment, and general health and respiratory status.

5.0 lysis of the NTS dosimetry database and the BU Work History

nnaire

The goal of the analysis was to determine whether cumulative lifetime gamma dose
calculated from the NTS dosimetry database is associated with certain parameters
collected within the BU work history questionnaire. We attempted to measure the utility
of these parameters to determine whether they could be used as a surrogate to estimate
cumulative dose.

We linked the work history questionnaire data on participants in the medical surveillance
program to available databases on external radiation dose (see below). Our review of
electronic databases identified the external radiation databases listed in section 4.1 of this
report as the databases having external exposure data of use for this project. We
attempted to use an NTS personnel database to provide an accurate estimate of an
individual’s working history; start, stop, and restart dates, duration, and cumulative work
years. However, we found that it was infeasible to use the personnel database to
calculate total time worked. In general, construction workers start, stop, and restart
employment frequently over their working lifetime as the demand for their work waxes
and wanes. We weren’t confident that the database accurately captured this phenomenon.
We therefore decided to determine an individual’s time worked based on the BU work
history questionnaire parameters. A master dose file then was constructed from all the
relevant databases listed in section 4.1 that contained external radiation data. The master
dose file was linked to the work history questionnaire (using the SSN). The effect of
several variables from the questionnaire (first hire decade, years worked, job
classification, etc.) on cumulative dose then was measured.

A data dictionary showing all of the variable names and definitions associated with the
work history database is included in Attachment B.

5.1 Description of NTS External Dosimetry Databases

The following databases were used in the assessment of cumulative external exposure:

NTPR database 1945-1962 45,308 records (film badge data)

19631983 1963-1983 140,769 records (film badge data)
1984 1984 34,728 records (TLD data)
1985 1985 36,290 records (TLD data)

1986 1986 34,387 records (TLD data)


DRAFT DRAFT DRAFT

Scenarios

Nevada Test Site

Background Information

The Nevada Test Site is located in the Nevada desert; dusty conditions were the norm
during all aboveground and underground work activities. Explosions from tests would
have created dust (including silica) that would have carried isotopes deep into the Iung.

Radiation Hazards:

DOE identifies all of the isotopes identified in each of the more than 900 nuclear tests
conducted at the Nevada Test Site together with the release amount in curies, the
maximum activity, and gamma exposure detected offsite, the maximum distance that
radiation was detected offsite, and other statistics (1). DOE indicates that 100
atmospheric nuclear tests were conducted at the Nevada Test Site during the period from
January 1951 and July 1962, and from January 1951 through September 1996, more than
800 underground nuclear tests resulting in more than 900 detonations were also
conducted at the Nevada Test Site. (2)

Releases usually contain multiple isotopes. Isotopes identified in the various releases
associated with nuclear tests include the following: Ar-37, Ar-39, Ba-139, Ba-140, and
Ba-140/La-140, Be-7, Ce-141, Ce-144, Cs-137, Cs-138, Cs-139, H-3 (tritium and
tritiated water), I-131, I-132, I-133, I-134, 1-135, and I-132/Te-132, K-40, Kr-85,
Kr-85m, Kr-87, Kr-88, Kr-89, Kr-91, La-140, La-142, Mn-54, Mn-56, Mo-99, Na-24,
Nb-95, Rb-88, Rb-88m, Rb-89, Rh-105, Ru-103, Ru-105, Ru-106, and Ru-106/Rh-106,
Sb-122, Sb-124, Sr-89, Sr-91, Sr-92, Tc-99, Te-132, W-181, W-187, W-188, Xe-127,
Xe-129m, Xe-131m, Xe-133, Xe-133m, Xe-135, Xe-137, Xe-138, Xe-139, Xe-140,
Y-91, Y-91m, Zr-95/Nb-95, and Zr-97/Nb-97. (1)

Radiation Exposures:

“The release of radioactivity from an underground test can occur:
e accidentally as a result of a containment failure;
¢ accidentally or deliberately as a result of post-event operations; or
e deliberately as a result of post-event controlled purging of gases from a
tunnel.”(2)

DOE identifies the following types of radiological releases and potential exposures
associated with nuclear tests at the Nevada Test Site:

e “A ‘test’ release (or an ‘uncontrolled’ release for DoD tunnel tests) has been
defined as a spontaneous release that occurred after a test but before postshot
drilling operations began.” “The pre-LTBT shaft and tunnel tests, where a
sampling conduit to the atmosphere was designed and placed in the test complex
for sampling of the particulate matter released, have been defined as ‘test/prompt


zero and 143 individuals had no records, in the 1970s 88% (418) were zero with no
missing records and in the 1980s 90% (1461) were zero. Although we were unable to
determine whether an individual had a complete dosimetric record, hard copy data (if
available) could be compared with the individual’s reported work period (or work period
specified in the personnel files) to determine if there is missing data. We were able to do
this on a smaller scale for 20 cases that an in-depth records review had been performed.
Of the 20 cases, 4 had no external radiation records within the electronic database, 3 had
partial records (not for the entire time they worked at the site and not for the entire time
indicated in the hard copy case file), and 13 had dose data covering the entire period
indicated in their work history. The completeness of the database and hard copy records
is discussed further in section xxx ~ In-depth Case Review.

We next examined cumulative lifetime dose as a function of job type. The self-reported
job titles listed in the BU work history form were categorized into job groups as follows:
Operating Engineers, Pipefitter, Sheet Metal Worker, Teamsters, Painters, Carpenters,
Laborers, Electrical workers, Ironworkers, Other Union, and Non-Union. Table 1 shows
the average cumulative lifetime dose by job class. The average dose is calculated for all
workers with any dosimetry record and includes zero values in the average. It is
interesting to note the number of workers with dosimetry records available by craft. It is
particularly interesting to note that the non-union and other union job categories are the
jobs with the largest percentage of missing records.

Table 2 shows the average cumulative lifetime gamma dose and beta dose by first year
employed at the NTS. As expected these numbers generally trend down over time.

Tables 3.1 through 3.10.4 show the cumulative lifetime gamma dose and beta dose by
decade first employed and years worked by job classification.

Several other parameters from the questionnaire were examined to determine their utility
in determining the completeness of the dosimetry records for purposes of completing a
dose reconstruction. If an individual indicates that he/she participated in a specific test or
specific tunnel work task (e.g. tunnel re-entry), this could be used to determine if there
were any missed dose records. According to NTS project staff, as well as former NTS
workers tunnel and reentry access logs were well maintained and could be a useful and
available reference for determining if an individual was involved in particular events,
The logs could provide a way to determine potential missed doses from internal
exposures, including radon exposures (see discussion of radon exposure below) during
tunnel work. It also appears that radiological characterization data is available by area
and even by underground test (828 total) and is contained within two separate databases
at the LANL and LLNL. Since these databases contain test specific nuclear performance
data including yield and residual nuclear fuels it is classified as Secret Restricted Data
(Bowen, 2001)

Table 4 shows the lifetime cumulative dose for individuals who reported that they had
been decontaminated for radioactive material contamination during their work at the NTS
and for those who indicated they had not been decontaminated (variable a12). It is


Count with Tount with
Gamma Dose | Average Beta Dose
Above record in Gamma | Standard | Maximum | record in Average | Standard | Maximum
Ground Dosimetry Dose Deviation Dose Dosimetry | Beta Dose | Deviation Dose
Tests Database (mrem) (mrem) (mrem) Database (mrem) (mrem) (mrem)
Yes 1880 3236 36210 173 703 6195
No 119 726 15985 39 254 4460
Number
() 505 1074 4850 138 614 4134
4 1513 2418 12865 123 514 4200
1 to 10 2219 3685 24580 116 489 3115
11 to 20 2295 3664 14791 106 249 1025
21 to 30 2427 2048 5890 39 93 325
31 to 40 3536 5832 36210 300 1000 5745
>40
Number of
Test Clean
ups
) 1123 2170 12815 138. 612 6135
1 1960 2783 13567 199 845 6195
1 to 10 3231 4469 24580 176 560 3115
11 to 20 2681 3617 14791 224 712 2935
21 to 30 2429 2323 7635 57 118 325
31 to 40 3897 6764 36210 75 347 2090



Sheetmetal Workers: Cumm Gamma Dose vs.
Years Worked (first worked 1960s)

200 +
180 4

160
140

120 4
100 +

80
60
40

20 4

<1 1-5 yrs 6-10yrs 10-20yrs >20 yrs

Years Worked

: : @ Series1



Teamsters: Cumm Gamma Dose vs. Years
Worked (first worked 1970s)

<1 1-5yrs 6-10 yrs 10-20 yrs >20 yrs
Years Worked

 Series1



|__ Sulfa-set - Skin 70. 53.85 1.49 0.79
Grout - Skin 76 57.58 1.64 0.83
Beryllium 53 59.55 2.45 4.15
Carpenters
Loud Noise 160 98.16 3.14 0.94
Vibration 145 90.06 2.75 1.10
Shotcrete 4105 72.44 2.30 0.99
Rock Dust 135 85.44 2.50 1.00
Diesel Smoke 141 89.24 2.77 1.02
Oil Fumes 122 80.26 2.29 1.05
Welding Fumes 144 91.14 2.90 1.06
Asbestos 106 80.30 2.08 0.99
Solvents 114 76.51 2.00 0.96
Epoxy 111 73.51 2.02 0.91
Sulfa-set 97 66.44 2.24 1.02
Grout 116 74.84 2.52 0.99
Solvents - Skin 106 69.28 1.85 0.88
Epoxy - Skin 104 68.87 1.79 0.90
Sulfa-set - Skin 89 60.54 1.87 0.94
Grout - Skin 103 69.13 2.08 0.97
Beryllium 25 30.12 2.44 1.00
Sheetmetal Workers
Loud Noise 35 97.22 3.17 0.89
Vibration 33 94.29 2.61 1.03
Shotcrete 14 45.16 1.74 0.73
Rock Dust 21 61.76 2.00 0.95
Diesel Smoke 28 84.85 2.14 0.93
Oil Fumes 22 64.71 1.82 4.04
Welding Fumes 36 97.22 2.63 0.97
Asbestos 27 84.38 1.96 0.98
Solvents 28 82.25 2.00 0.77
Epoxy 19 57.58 1.68 0.75
Sulfa-set 9 29.03 1.44 0.73
Grout 12 38.71 1.75 1.06
Solvents - Skin 28 80.00 1.54 0.51
Epoxy - Skin 16 48.48 1.31 0.48
Sulfa-set - Skin 9 28.13 1.22 0.44
Grout - Skin 10 31.25 1.30 0.67
Beryllium 4 18.18 2.25 0.96
Teamsters
Loud Noise . 205 94.91 3.00 0.98
Vibration 185 86.45 2.79 1.15
Shotcrete 88 46.32 2.11 1.03
Rock Dust 142 69.95 2.47 1.09
Diesel Smoke 199 93.87 3.12 0.99
Oil Fumes 164 79.23 2.54 1.12
Welding Fumes 130 63.11 2.02 1.04



Attachment |:

Nevada Test Site Building Trades Medical Screening Program: Summary Of Radiation
Exposure Date Analyses, All Workers Interviewed By June 30, 2003, Construction
Worker Exposure And Job Task Data Project, June 8, 2004.


12
10

oN Fk OD OH

Teamsters: Cumm Gamma Dose vs. Years
Worked (first worked 1980s)

<1 1-5 yrs 6-10 yrs 10-20yrs >20yrs
Years Worked

M Series |



Appendix A -- Case File Results Review

Case 1:

Individual indicated that he worked from 1954-1959 and again from 1989 to 1998. Full case file
indicates he was not hired until 8/58 and the summary report indicates he had dosimetry records
for the following time periods: 1958, 1960-1962, 1964-1989. External dosimetry database
records were consistent with hard copy records

Case 2:

Individual indicated that he worked from 1964-1995. Full case file indicates external dosimetry
data for the following periods: no data for 1964, yearly summary data for 1966 and 1969, all
other periods through 1995 included regular data. External dosimetry database records indicate
no dosimetry records for this individual from 1964-1986 but the database does include regular
records between 1987-1992. Hard copy records indicate extensive tritium sampling (135
samples) and database records indicate 130 samples. Hard copy records indicate an assigned
dose from tritium exposures for the periods from 1972-1973 and 1976-1984. The calculated
tritium doses were reviewed using the same assumptions as the NTS staff used and using
CINDY version 1.4 with ICRP 30 tritium model and doses consistent with the reported doses
were obtained..

Case 3:

Individual indicate he worked from 1962-1992. Full case file indicates external dosimetry data
for the entire period from 1962-1992; 1963-1971 is only yearly summary data. External
dosimetry database records are consistent with hard copy records. Hard copy records and
database records indicate 13 tritium samples during the 1962-1963 time period. The calculated
tritium doses were reviewed using the same assumptions as the NTS staff used and using
CINDY version 1.4 with ICRP 30 tritium model and doses consistent with the reported doses
were obtained..

Case 4:

Individual indicate he worked from 1951-1952 and again from 1957-1994. Full case file
indicates external dosimetry data for the entire period -- 1951-1952 (yearly summary data),
1968-1971 (yearly summary data) and other time periods had regular data. External dosimetry
database records are consistent with hard copy records. Hard copy records indicate tritium
sampling during 1959-1960, 1963, 1976-1977, 1980-1988 with a dose assigned for the time
period from 1981-1984, Database records indicate 53 tritium samples during 1976-1985 and 1-7
samples in 1962-1963 (No ID# for this database so could not determine if had the correct
individual). The calculated tritium doses were reviewed using the same assumptions as the NTS


the ventilation equipment is working. However, the levels immediately begin to
rise once the system is shut down. The radon levels, which were reported for
several tunnels in area 12, were much higher on average for G tunnel that,
according to the report, was the result of "a lower ventilation rate in conjunction
with the more highly fractured nature of the 'welded tuff rock formation." The
lowering and/or elimination of ventilation was a common circumstance in the
tunnels as the “button-up" phase approached. During these final steps prior to an
event, access to the bypass and line-of-site tunnels were restricted at times to that
of small crawl tubes that were not able to maintain the necessary ventilation level
for safe working conditions. The decrease in ventilation rate is likely to have lead
to increased radon levels in these instances. Further, ventilation in the early years
has been described as "poor" by former workers in a focus group, which is likely
considering that several crews worked in different headings of a single tunnel at
one time and often worked in less ventilated side drifts.

Based on the in-depth case reviews (see section 7) it was apparent that
approximately 25% of cases we reviewed either had no external dose records in
the electronic database or were missing some time periods of monitoring results
and we could not determine missing periods of dosimetry data for the larger
cohort

It was unclear whether the primary work related variables were predictive of
overall cumulative gamma dose. Even for the job type variable we could only
evaluate the average lifetime cumulative dose as a function of job type for all
individuals who listed a job. However, an individual could have had several jobs
and that individual’s overall cumulative dose would have been included in several
different job type evaluations. A more detailed analysis of the cumulative dose as
a function of job for the period the individual worked that job, could not be
achieved given the questionnaire’s data limitations.

Through our analysis we did identify several items that we believe might be helpful in
estimating annual doses for former workers for compensation cases.

1.

Some questions in the most recent BU work history questionnaire may be useful
in verifying dosimetry data and also in determining presence at certain events for
which dose information is not included in the individual’s hard copy records.
This could be especially useful for estimating radon dose or possibly dose
associated with other radionuclides that were present in the event area. The
primary questions, which may be useful in this verification process, include:
questions related to event (tunnel, shaft, or above ground test) work and which
event they worked in, question of whether they ever were decontaminated (and
possibly when and where), question regarding badge use (just recently added to
BU questionnaire so not evaluated in this report).

Event access logs and possibly the entire event log may prove to be very
important especially since it appears that at least in some cases only some workers
were monitored for internal exposures.


Based on this preliminary analysis of the work history questionnaire variables compared
with cumulative lifetime gamma dose for the Boston University cohort (2753 medical
screening participants) we felt that development of a statistical model to estimate dose
based on the work history questionnaire variables was not achievable. There are several
reasons we feel that this should not be performed with data available for our study

including:

5.3 __ Internal Dosimetry Analysis

We also made an attempt to examine the impact of the workplace survey variables on
lifetime internal dose (50 year CEDE). With the exception post-1989 databases, the NTS
databases did not include much internal dose data. In order to evaluate internal dose, we
used dose summary reports (Radiation Exposure History) that were provided by the
Dosimetry Research Project to individuals who participated in the medical screening
program. BU created a database with the summary dose information for all participants
who provided their dose summary report to the program. The database included external
dose information for 1752 individuals and internal dose information for 100 individuals.
The jobs/unions with the most significant internal dose, based on this data, were the
operating engineers and the laborers. They accounted for more than half of the former
workers with internal dose records. 69 of 70 individuals reported working in tunnel tests,
43 of 70 indicated they had been involved in above ground tests (1951-1962), and 42 of
69 indicated that they had been decontaminated. Individuals who reported to participate
in tunnel tests, atmospheric testing, or being decontaminated had higher average lifetime
intemal dose records than those who did not take part. Since there was only internal dose
information for 100 individuals, (the data did not include potential dose from radon
exposures) in our opinion analysis of the work history parameters as a function of total
lifetime internal dose would not be useful.

Based on this preliminary analysis of the work history questionnaire variables compared
with cumulative lifetime gamma dose for the Boston University cohort (2753 medical
screening participants) we felt that development of a statistical model to estimate dose
based on the work history questionnaire variables was not achievable. There are several
reasons we feel that this should not be performed with data available for our study

including:

1. We believe that potentially a relatively large portion of an individual tunnel
workers dose could have been due to internal dose and we did not have summary
internal dose data in the NTS database (database included primarily bioassay
data). The available dose data did not account for radon exposure. However,
radon was a significant exposure in the tunnels. The NTS project reported on
available radon data. Radon measurements were collected and analyzed for
several tunnels in 1984 and reported in the document, "Survey of Radon and
Radon Daughter Concentrations in Selected Rainier Mesa Tunnels." In the
tunnels, the radon working levels fall well below the EPA standard of 0.33 when


Laborers: Cumm Gamma Dose vs. Years Worked |
(first worked 1980s)

300 ~wessase

250 2 :

200 oe ey

150 4 S — @ Series‘
100 oe

50

<1 1-5 yrs 6-10 yrs 10-20 yrs >20 yrs
Years Worked



std. Dev

Were there times you
did not wear your
badge? n=385 _
Yes_ 49 12.73
No 336 87.27
What were the
reasons you did not
wear your badge?
Badge/dosimeter not
provided n=50
Yes 10 20
No 40 80
'You were asked not to
wear it n=50
Yes 13 26
No 37 74
Close to exposure
limit and did not want
to go over n=50
Yes 5 40
No 45 90
Non-exposure area,
not needed to wear
badge n=52
Yes 21 40.38
No 31 59.62
Lost badge, did not
ask to replace n=49
Yes 2 4.08
No 47 95.92
Did you ever work
with or around
plutonium? n=739
Yes 102 13.8
No 136 18.4
Don't Know 501. «|___—«a67.79



Teamsters: Cumm Gamma Dose vs. Years
Worked (first worked 1950s)

3000
2500 +
2000 |
1500 +

| |W Series1

1000
500 J

<1 1-5 yrs 6-10 yrs 10-20yrs >20 yrs
Years Worked



319

B 15.64
E 704 34.53
G 817 40.07
I-J-K 295 14.47
N 1400 68.66
P 811 39.77
T 1430 55.42
U 91 4.46
Xx 156 7.65,
Y 80 3.92
16 526 25.8
Mining in Tunnels n=1997
Performed 650 32.55
Present 365 18.28
Neither 982 49.17
onstruction in Tunnels =2008
Perfomed 1044 51.99
Present 287 14.29
Neither 677 33.72
Pre-Shot LOS Pipe Work in Tunnels n=1137
Performed 399 35.09
Present 239 21.02
. Neither 499 43.89
\Pre-Shot LOS Pipe - Instalied / Modified Flanges in Tunnels n=426
Yes 144 33.8
No 282 66.2
IPre-Shot LOS Pipe - Worked In / Around A-Box in Tunnels n=247
Yes 167 67.61
No 4 80 32.39
Pre-Shot LOS Pipe - installed / Modified Cone at A-Box in
[Tunnels n=243
Yes 44 18.11
No 199 81.89
forked at Test Chambers in Tunnels n=246
Yes 189 76.83



staff used and using CINDY version 1.4 with ICRP 30 tritium model and doses consistent with
the reported doses were obtained..

Case 5:

Individual indicated he worked from 1965-1995. Full case file indicates external dosimetry data
for the entire time period with 1965-1972 having annual summary data only and 1973-1995
including regular sampling data. External dosimetry database records include no data for the
time period from 1963-1986 but the database does include records for the time period from
1987-1992. Hard copy records do not indicate any bioassay data and no bioassay records were
found in the databases.

Case 6:

Individual indicated he worked from 1959-1995. Full case file indicates external dosimetry data
for the time period from 1960-1995 with 1960-1971 having only annual summary data and 1972-
1995 including regular sampling data. Tritium sampling for hard copy records and database are
consistent with sampling from 1976 through 1983. Hard copy dose records indicate dose
assigned for period from 1976-1983. Hard copy record indicates sampling in 1972, 1974 and
1984 with no dose assigned. The reason for not assigning a dose for 1984 is given in the hard
copy records (result would be less than 10 mrem CEDE) however, no reason is given for not
assigning a dose for 1972 or 1974 although it is apparent that the dose would have been very
small. Hard copy records indicated | sample for plutonium-239 in 1974 however, the database
did not indicate any plutonium sampling. The calculated tritium doses were reviewed using the
same assumptions as the NTS staff used and using CINDY version 1.4 with ICRP 30 tritium
model and doses consistent with the reported doses were obtained..

Case 7:

Individual indicated he worked from 1959-1995. Full case file indicates external dosimetry data
for the time period 1959-1995 with only annual summary doses for the time period from 1969-
1971, External dosimetry database includes monitoring data for the entire period with the data
being consistent except for a 1963 annual dose in the database of 1765 mrem and the hard copy
record shows a dose of 1825 mrem. Hard copy and database records indicate tritium sampling
1959 through 1963 (both include 18 samples) with a dose assigned for the time period from
1961-1963. The calculated tritium doses were reviewed using the same assumptions as the NTS
staff used and using CINDY version 1.4 with ICRP 30 tritium model and doses consistent with
the reported doses were obtained.

Case 8:

Individual indicated he worked from 1961-1968 and again from 1975 through 1998. Full case
file indicates external dosimetry data for time period from 1963 through 1998 with no data for


o¢ CrBfonm

[Worked During Atmospheric Nuclear Testing Period
Yes 756 27.46
No 1997 72.54
Number of Atmospheric Nuclear Events While Within NTS n=698
ie) 37 5.3
1-10 442 63.32
11-20 76 10.89
21-30 38 5.44
31-40 27 3.87
>40 78 41.17
Involved in Clean-up for Atmospheric Nuclear Events n=678
—L () 308 45.43
1-10 236 34.81
11-20 48 7.08
21-30 23 3.39
31-40 16 2.36
>40 AT 6.93
Ever Worked in Tunnel / Tunnel Yard Area n=2750
Yes 2039 74.15
No 7i1 25.85
Number of Tunnels Tests Worked On n=1967.
te) 101 §.13
1-10 1257 63.9
11-20 346 17.59
21-30 117 5.95
31-40 50 2.54
>40 96 4.88
Number of Tunnel Tests For Which Performed Re-entry
(Work n=1929
0 653 33.85
1-10 959 49.71
11-20 180 9.33
21-30 62 3.21
31-40 22 1.14
>40 53 2.75
[Tunnels Worked On: n=2039
A 107 §.25



IBEW: Cumm Gamma Dose vs. Years Worked
(first worked 1970s)

: § Series1

<1 1-Syrs 6-10 yrs 10-20yrs >20 yrs
Years Worked



The dosemast database contains 74,817 records for the years between 1986 and 1993.
This database contains deep dose results (74,817 records with 709 (0.9%) greater than
zero), shallow dose results (74,817 results with 610 (0.8%) greater than zero), eye dose
(74,817 records with 41 greater than zero), extremity dose (74,817 records with 1062
(1.4%) greater than zero), tritium dose (74,817 records with 3 records greater than zero),
and internal dose (74,817 records with 36 records greater than zero).

The dead.mdb database contains bioassay data for the period from 1955 through 1963
with a total of 32,072 records representing 3257 unique last names. Many individuals
had only | bioassay result (1264 individuals). The type of analysis included in the
database were as follows: I-131 (36 results), U-235 (16 results), Pu-239 (318 results),
Gross Alpha (10,483 results), Gross Beta (4583 results), Gamma Spec (21 results), Gross
Fission Products (1326 results), I-133 (12 results), I-135 (12 results), Plutonium (35
results), Sr-90 (15 results), Tritium (7376 results), and Uranium (95 results).

The midbio.mdb database contains bioassay data for the period from 1964 to 1987 with a
total of 19,980 records representing 2000 unique social security numbers. Approximately
1100 individuals had only 1 or 2 results in the database.

5.2 Analysis Results

An initial query of the data indicated that there were 1997 individuals with a work history
questionnaire who had at least one record within the combined external dose database.
The overall number of individuals with a work history questionnaire is 2753. The table
below summarizes the lifetime cumulative gamma dose based on the NTS dosimetry
database for individuals who were monitored.

Summary of lifetime cumulative gamma dose
for BU screening participants

Cumm Gamma Dose (mrem) Number of Percentage
Individuals of screening

participants
(2753)

No Records 756 27%

0 1275 46%

>0- 100 170 6%

101-499 189 T%

500-2,000 156 6%

2,001 — 5,000 135 5%

We next assessed the effect of t the decade an individual started work at the NTS on their
cumulative dose. The cumulative gamma dose and beta dose records for individuals who
participated in the BU screening program was examined by the decade they began work.
For gamma dose records, in the 1950s 19.6% of the individuals (55) had a cumulative
dose of zero, in the 1960s 32% (218) were zero, in the 1970s 77% (364) were zero and in
the 1980s 88% (1430) were zero. For beta dose in the 1950s all cumulative doses were
either zero or had no records at all (273 missing records), in the 1960s 85% (457) were


Nevada Test Site Building Trades Medical Screening Program

Summary Of Worker Demographics and Work History Information On
Radiation Hazards

All Workers Screened by December 31, 2002

Construction Worker and Job Task Data Project

NIOSH Contract #200-2002-00433


200
180

160 |

140

120 4

100

80 4

60
40
20

Teamsters: Cumm Gamma Dose vs. Years
Worked (first worked 1960s)

<1 1-5 yrs 6-10 yrs 10-20yrs >20 yrs
Years Worked

Bm Series1|



Laborers: Cumm Gamma Dose vs. Years Worked

8000 5
7000
6000 |
5000 |

4000
3000

2000 4

1000

0 ki

(first worked 1960s)

| |i Series1

<1 1-Syrs 6-10 yrs 10-20 yrs >20 yrs
Years Worked



Sheetmetal Workers: Cumm Gamma Dose vs.
Years Worked (first worked 1950s)

600
500
400 +
300

| Series1

200
100

0 :

<1 1-5 yrs 6-10 yrs 10-20 yrs >20 yrs
Years Worked



Count with

Count with
Gamma Dose! Average Beta Dose,
record in Gamma | Standard | Maximum | recordin | Average | Standard | Maximum
Dosimetry Dose Deviation Dose Dosimetry| Beta Dose; Deviation Dose
Decon Database {mrem) {mrem) (mrem) | Database |_(mrem) (mrem) {mrem)
Decon-yes 872 1396 3088 36210 872 165 637 6135 |
Decon-no 1871 296 1408 12815 1871 33 272 195



IBEW: Cumm Gamma dose vs. years worked
(first worked 1950s)

4000 -
3500
3000 +
2500
2000

<1 1-5 yrs 6-10 yrs 10-20 yrs >20 yrs
Years Worked



Frequency of Worker Reported Work in NTS Areas (n=2758

1 1175 42.6
2 1544 55.98
3 1852 67.15
4 1039 37.67
5 1389 50.36
6 1710 2758
7 1030 37.35
8 965 34.99
9 1148 41.62
10 1079 39.12
ak! 968 35.1
12 2403 87.13
14 843 30.57
15 1145 41.52
16 1174 42.57
47 1183 42.89
18 1110 40.25
19 1524 55.26
20 1525 55.29
22 831 30.13
[23 1312 47.57
25 1391 50.44
26 819 29.7
27 943 34.19
28 668 24.22
29 733 26.58
30 773 28.03
[Atlas (NLV), 135 4.89
ency of Worker Reported Work in NTS Areas (n=2039
Tunnel A
Tunne! B 319 11.57
Tunnel E 707 25.63
Tunnel G 820 29.73
Tunnel I-J-K| 295 10.7
Tunnel N 1406 50.98
Tunnel P. 813 29.48
Tunnel T 1133 41.08
Tunnel U 92 3.34
Tunnel X 157 5.69
Tunnel ¥ 81 2.94
Tunnel 16 527 19.11



Other Unions: Cumm Gamma Dose vs. Years
Worked (first worked 1960s)

6000
5000
4000
3000
2000
1000

0

<1 1-Syrs 6-10yrs 10-20 yrs >20 yrs
Years Worked



Worker Responses to Radiation Monitoring & Incident Questions

>

B Qliection : j ; May Meare) mereSia eu aam
Did you ever have to
be decontaminated
because of radiation
exposure? n=2743
Yes 872 31.79
No 1871 68.21
if yes, how many
times? n=773
1 276 35.71 11.75 41.35
2 140 18.11
3 112 14.49
4 32 4.14
5 37 4.79
6 19 2.46
7 3 0.39
8 7 0.91
9 3 0.39
10 31 4.01
11 2 0.26
12 10 1.29
15 14 1.81
16 1 0.13
18 2 0.26
20 10 1.29
22 1 0.13
24 4 0.13
25 2 0,26
30 9 1.16
36 1 0.13
40 6 0.78
50 12 1.55
60 1 0.13
75 1 0.13
99 34 44
100 2 0.26
150 1 0.13
400 1 0.13
600 1 0.13
750 1 0.13



Count with Gamma Average Standard Count with Beta Average Standard
Dose record in Gamma Dose Deviation Maximum Dose record in Beta Dose | Deviation Maximum

Year Dosimetry Database (mrem) (mrem) Dose (mrem) |Dosimetry Database} _(mrem) (mrem) Dose (mrem)
1954 5 1424 4177 2660
1952 15 1542 1772 5734
1953 27 1929 1348 5370
1954 12 414 728 2670
1955 27 848 899 3310
1956 13 2639 7734 28020
1957 154 957 41144 5310
1958 192 496 677 3805
1959 149 326 606 2635
1960 208 57 340 4600
1961 368 472 974 4675
1962 616 520 899 4690
1963 490 142 409 2905
1964 468 48 245 3530 1 50 50
1965 468 92 444 4380 0 te) 0
1966 479 137 481 4510 479 60. 318 3440
1967 428 107 386 3540 428 53. 244 2745
1968 437 48 155 1325 437 33 220 2560
1969 404 19 138 2210 404 6 50 690
1970 381 27 100 845 381 18 112 1560 |
1971 356 26 117 1045 356. 19 132 1940
1972 321 28 195 2780 321 40 239 2545
1973 282 5 31 325 282 1 9 145 |
1974 297 4 _ 25 345 297 0.5 8 135
1975 293 3 20 175 ____ 293 2 “12 125

| 1976 274 3 29 460 274 0° 0 eo |
1977 261 2 20 295 261 1 14 _215
1978 _ 262 4 26 360 262 0.2 4 65

| __1979 236 05 6 __70 236 0 Oo oe.
1980 238 1 7 70 238 0.4 7 105

~ 1981 241 tt 7 90 244 0.4 7 105

1982 237, 1 10 140 237 1 14 210
1983 252 03 3 40 252 0.2 3 50

| 1984 1148 3 31 620. | 1148 1 9 185
1985 1216 4 _ 37 675 1216 3 34 840
1986 1186 31 205 3040 1186. 14 110_ 1890

1987 1179 6 44 903 1179 14_ 136 3206

1988 a1 2 19 355 | 141 3 34 _747
1989 ] 1048 0.6 7 195 L 1048 1 12 259



Mean Age & Periods of NTS Work by Trade Union

Laborers 630 61.11 10.68 12.21 8.36 1969.55 1984.79 | 15.13
IBEW. 437 64.06 10.30 9.40 7.68 1969.95 1983.75 16.49
Operating Engineers] 642 61.72 11.48 12.56 8.42 1969.51 1985.06 | 14.93
Ironworkers 138 61.74 11.67 10.98 7.85 1969.22 1983.19 16.76
Plumbers / Pipefitters|__ 145 62.73 11.37 9.68 7.43 1970.47 1986.23 14.30
Carpenters 166 63.56 11.78 | ____ 9.40 8.20 1968.55 1981.60 18.52
Sheetmetal 37 58.41 10.65 8.33 7A7 1974.19 1984.32 15.89
Teamsters 222 63.80 9.90 14.75 7.95 1969.81 1988.37 12.04
Painters _ 23 64.83 8.48 11.39 7.53 1970.48 1984.35 16.00

IGAN 128 62.92 10.67 16.95 7.61 1969.27 1989.16 | 11.17

Other 158 60.13 11.29 12.60 8.22 1968.59 1984.58 | 15.88
Non-union 445 63.76 9.77 14.57 8.75 1967.47 1985.76 | 14.89



Laborers: Cumm Gamma Dose vs. Years Worked
(first worked 1950s)

7000
6000
5000

4000 4
3000
2000
1000

oJ

1-5 yrs

Years Worked

i |m Series
@ Series2

6-10 yrs 10-20 yrs >20 yrs



IBEW: Cumm Gamma Dose vs. Years Worked
(first worked 1960s)

4000
3500
3000
2500
2000
1500
1000

500

<1 1-5 yrs 6-10 yrs’ 10-20 yrs >20 yrs
Years Worked

7 Series1 |



Those surface and near-surface tests, that were non-nuclear tests designed to
determine the extent of debris scattering, have been defined as ‘test/plutonium
dispersal’ releases.”

e A “controlled” release was “a planned, filtered, release frequently performed to
reduce airborne radiation levels in the working environment” predominantly from
tunnels, although this type of release “also occurred from shaft tests”.

¢ “*Drillback’ releases occurred during post-shot drilling operations to recover
samples; these releases were either filtered or unfiltered. After drillback
operations were completed, a ‘cementback’ occurred where the drill hole was
sealed with a plug and cemented to the surface.” Releases also occurred during
“cementback” operations.

« “Gas sampling’ releases occurred during gas sampling operations, either before
or after any post-shot drilling operations commenced.”

e “Late-time seepage’ releases occurred when noble gases have leaked from test
sites after all operations in the area have ceased. These releases “could exist from
a few hours to even weeks after all other operations in the area have ceased.”
(DOE 1996)

Other activities cited that brought radioactive isotopes to the surface from the explosion
site include:

e “Cable pull” defined as “Recovery of a cable placed near a nuclear explosion.
The cable ran to the surface and was pulled free shortly after zero time. The
debris captured on the bottom end of the cable was analyzed to assess device
performance.”

e “Catcher pull” defined as “Recovery of a debris catcher, placed near a nuclear
explosive, by pulling on the attached cable and thus returning the catcher to the
ground surface. This operation is usually accomplished within minutes to hours
of zero time.” (DOE 1996)

A recent report (Bowen, SM 2001) shows estimates of the radiation source term (decay
corrected to 1992) from all the underground tests in each area. The table indicates a
significant amount of plutonium-238 and plutonium-239 (both most likely from the
device component) with the total for all areas which included underground testing
estimated as 3.95E4 Curies of Pu-238 and 1.6E5 Curies of Pu-239. (Bowen, SM 2001)

According to Bowen most of the plutonium would have been trapped in the cooling melt
after the nuclear explosion with only a small proportion in the escaping cavity gases. (
Bowen, SM 2001) Information regarding the amounts of plutonium that may have been
released during tunnel venting could not be located for this project. Similarly little
information regarding the potential exposures to plutonium within the tunnels could not
be ascertained although Skrable (1995) does note that soil samples taken prior to the
decontamination work in the E-tunnel in 1994 had Cesium (Cs-137) to Plutonium (Pu-
239) ratios ranging from 10:1 to 400:1 on an activity basis. In the early NTS years, a
many gross alpha nasal swipes were collected. Overall, however, a small percentage of
workers at the NTS were monitored for plutonium.


Frequency of Worker Reported Work at Other Doe Sites

Alaska / Pacific Tests 46 1.67
Argonne 4 0.15
Atomics International (CA) 1 0.04
Brookhaven National
Laboratory 2 0.07
Fermi National Accelerator
Lab (Illinois) 1 0.04
Fernald Materials Production
Center (OH) 4 0.15
Hanford Site (WA) 36 1.31
Idaho Mational Engineering &
Environmetnal Lab 22 0.8
{owa Ordnance Plant 1 0.04
Lawrence Livermore National
Lab 28 1.02
Los Alamos National Lab 47 17
Monticello Site (UT) 1 0.04
Mound Plant (OH) 1 0,04
Nevada Test Site 77 2.79
Oak Ridge 6 0.22
Other 208 7.54
Other Test Sites 19 0.69
Paducah 5 0.18
Pantex Plant 5 0.18
Portsmouth 8 0.29
Rocky Flats 28 1.02
Sandia National Lab 29 1.05
Savannah River 10 0.36



wear your badge?

|Worker Reported Periods of No Radiation Monitoring by Union (Were there times you did not)

Laborers n=65, missing=565
4 16.92
IBEW n=79, missing=358
10 12.66
Operating Engineers n=76, missing=566
10 13.16
Ironworkers n=6, missing=132
1 16.67
Plumbers & Pipefitters n=32, missing=113
5 15.63
Carpenters n=28, missing=138
4 14.29
Sheetmetal Workers n=4, missing=33
1 25.00
Teamsters n=33, missing=189
2 6.06
Painters n=23, missing=23
IGAN n=4, missing=124
0 it}
Other n=21, missing=137
2 9.52
Non-union n=100, missing=345
13 13.00



Non-Union: Cumm Gamma Dose vs. Years
Worked (first worked 1950s)

6000
5000 |
4000 4
3000 4
2000 4
1000 +4

1-5 yrs 6-10 yrs 10-20 yrs >20 yrs
Years Worked



We queried the internal dose database (dead) to determine whether individuals
listed in the Ul6a event in 1962, which has been cited as an event which involved
a plutonium release, were monitored for plutonium or gross alpha. It was
determined that only 3 of 221 RECCO employees in the event database had been
monitored for plutonium in 1962 and none of the RECCO employees were
monitored for gross alpha. This suggests the need to verify by access logs who
worked in certain areas or during certain events.

7.0 ____In-depth Case Review

Boston University obtained full case files for 20 individuals who had participated in the
medical surveillance program. The cases, which were obtained during the early stages of
the medical screening program, were not selected based on a specific sampling approach.
The intent was to obtain a cross section based on types of exposures encountered and
complexity of the exposure history. We compared the data in the full case file with that
in the database to determine the accuracy of the database. We also reviewed the work
history of the individual (based on the self administered occupational health
questionnaire — see Attachment A) to determine if the individual had dosimetric data for
all the years they worked at the site.

The in-depth review of the 20 individuals’ NTS dose reconstruction case file suggests
that some data exist in microfiche format that is not included in the electronic database.
While this may not affect individual reconstruction efforts it may hinder efforts to
understand the overall worker population.

In general, the data for the 20 cases reviewed agreed with the electronic database.
However, there were several individuals for whom all or part of their external dose data
was not included within the electronic database. There were also some cases where the
individual did not have dosimetry data (in the hard copy records or the electronic
database) for all of their reported work history (self reported on the Boston University
questionnaire). Additionally, there were some instances where NTS noted in the
individual’s case file that there was not dosimetry information for their entire work
history (based on the NTS hire date). There could be several explanations for these
findings including: 1) individual misreported his work history, 2) individual worked for a
period of time and then left and then came back, 3) individual worked in an area not
requiring dosimetry, and 4) individuals worked in an area requiring dosimetry but the
data could not be located.

The external dosimetry data included within the full case file included computer printout
data or microfiche printouts. In some cases, when the computer printouts had no value
listed for a dosimeter reading, the computer punch cards were reviewed. The actual film
and TLD analysis data was not reviewed. Again, when electronic data existed it was in
good agreement with the hard copy file.

The internal dosimetry data within the hard copy records was generally in good
agreement with the electronic data with a few important exceptions (e.g., a case with a


180
160

140 +

120
100
80
60
40

20 -

Carpenters : Cumm Gamma Dose vs. Years
Worked (first worked 1960s)

<1 6-10 yrs 10-20 yrs >20 yrs
Years Worked

Series!



Ironworkers: Cumm Gamma Dose vs. Years
Worked (first worked 1960s)

10000 -
8000 -]
6000 +

4000 -
2000 -

1-5 yrs 6-10 yrs 10-20 yrs >20 yrs
Years Worked



problems in the bioassay databases which appear to be data entry type problems
(e.g., Pu-239 bioassay results in the dead bio database which make no sense —
2.7X105-24). Any sense of the magnitude of the problem?

Three individuals who had alpha nasal smears taken (pre-1965) did not have an
internal dose assigned. This discrepancy may indicate that there is a population of
individuals for whom there could be a significant missed dose for plutonium
especially in the early years of testing.

None of these workers has an estimate of an occupational dose from radon
exposures. Since the majority of the workers had at some point worked as tunnel
workers it seems that this could have been a significant exposure.

The Dosimetry Research Project Database (DRP) was established by the U.S.
DOE under the direction of the DOE’s Nevada Operations Office in January
1978. The DRP was established to collect, organize, and tabulate dosimetry and
exposure source documents; create and maintain a master dosimetry file; respond
to exposure history requests; and publish an historical report on Radiation Safety
in the Nuclear Testing Program. The DRP has not been used previously to
estimate individual and/or group cumulative exposure for compensation purposes.
This project has attempted to validate the DRP against a limited set of paper
records as well as against the reported experience of several thousand former NTS
construction worker participants in the DOE funded medical screening and
surveillance program. The difficulties encountered using a system based on
inconsistent job categories, frequent start and stop employment dates, and other
data problems specific for a construction-based work force suggest the
impracticality of using this system for compensation.

8.0 Recommendations

Based on our review of the NTS dosimetry data along with a sampling of the associated
hard copy records we offer the following recommendations with regard to a dose
reconstruction program for NTS workers.

1.

A supplemental set of site-specific questions regarding work at the test site
including information on area or event and some questions related to radiation
monitoring may be useful in determining the completeness of the dosimetry
records.

Access logs for all events seem to be an essential piece of data to verify presence
at different events and may be important since it appears that not all workers were
monitored (at least for internal exposures) during events.

Validation of electronic database would be recommended prior to aggregate use
of the data.

External and bioassay data should be verified against laboratory records. It
appears that even for the in-depth NTS dose files this verification was not
performed.

Caution should be used in using co-worker data since the nature of the
construction workers work, especially between events, appears to be highly
variable.


Since the nuclear testing moratorium took effect in 1992, the work force at the NTS has
dwindled to 2,600 full-time employees, and many of the construction workers have
moved on to the Yucca Mountain Project and other large projects in the Western United
States. Under the direction of the Department of Energy (DOE), Nevada Test Site use has
diversified into many other programs such as hazardous chemical spill testing, emergency
response training, conventional weapons testing, and waste management and
environmental technology studies.

Atmospheric weapons testing resulted in environmental radiation contamination in which
parts of the NTS workforce were exposed following post-shot activities at ground zero as
well as accidental contact with contaminated zones. Underground nuclear weapon
testing, in contrast to atmospheric testing, was designed to maximize hazard containment.
Nevertheless, accidental radiation releases occurred throughout the underground testing
period. The DOE has attempted to identify all of the isotopes identified in each of the
more than 900 nuclear tests conducted at the Nevada Test Site together with the release
amount in curies, the maximum activity, and gamma exposure detected offsite, the
maximum distance that radiation was detected offsite, and other statistics (DOE 1996).

Releases usually contain multiple isotopes. Isotopes identified in the various releases
associated with nuclear tests include the following: Ar-37, Ar-39, Ba-139, Ba-140, and
Ba-140/La-140, Be-7, Ce-141, Ce-144, Cs-137, Cs-138, Cs-139, H-3 (tritium and
tritiated water), I-131, I-132, 1-133, 1-134, I-135, and I-132/Te-132, K-40, Kr-85,
Kr-85m, Kr-87, Kr-88, Kr-89, Kr-91, La-140, La-142, Mn-54, Mn-56, Mo-99, Na-24,
Nb-95, Rb-88, Rb-88m, Rb-89, Rh-105, Ru-103, Ru-105, Ru-106, and Ru-106/Rh-106,
Sb-122, Sb-124, Sr-89, Sr-91, Sr-92, Tc-99, Te-132, W-181, W-187, W-188, Xe-127,
Xe-129m, Xe-131m, Xe-133, Xe-133m, Xe-135, Xe-137, Xe-138, Xe-139, Xe-140,
Y-91, Y-91m, Zr-95/Nb-95, and Zr-97/Nb-97. (DOE 1996)

Radiation Exposures:

“The release of radioactivity from an underground test can occur:
¢ Accidentally as a result of a containment failure;
e Accidentally or deliberately as a result of post-event operations; or
¢ Deliberately as a result of post-event controlled purging of gases from a
tunnel.”(DOE 2000)

DOE identifies the following types of radiological releases and potential exposures
associated with nuclear tests at the Nevada Test Site:
¢ “A ‘test’ release (or an ‘uncontrolled’ release for DoD tunnel tests) has been

defined as a spontaneous release that occurred after a test but before post-shot
drilling operations began.” “The pre-LTBT shaft and tunnel tests, where a
sampling conduit to the atmosphere was designed and placed in the test complex
for sampling of the particulate matter released, have been defined as ‘test/prompt
particle sampling releases. The cratering Plowshare tests, where the test was
designed to produce a throw-out of earth, have been designated as ‘test-crater’
releases. Releases from surface tests have been categorized as ‘test/surface’.



Phas UES CHPLONs

Worked on Cage

Yes
No
Participated in Drillbacks n=390
Yes 197 50.51
No 193 49.49



Plumbers/Pipefitters: Cumm Gamma Dose vs.
Years Worked (first worked 1950s)

1200
1000 4
800 +
600 4
400 4
200 4

1-5 yrs 6-10 yrs 10-20 yrs >20 yrs
Years Worked



Asbestos 97 51.87 2.04 1.09
Solvents 134 64.42 2.28 1.07
Epoxy 97 49.24 1.93 0.96
Sulfa-set 67 36.41 1.70 0.98
Grout 96 48.48 2.13 1.04
Solvents - Skin 123 59.42 2.15 1.14
Epoxy - Skin 75 37.88 1.59 0.81
Sulfa-set - Skin 51 27.42 1.59 0.90
Grout - Skin 75 37.69 1.84 0.99
Beryllium 29 21.01 2.10 0.98
Painters
Loud Noise 21 91.30 2.90 1.22
Vibration 17 73.91 2.76 1.20
Shoterete 5 25.00 2.20 0.45
Rock Dust 10 50.00 2.50 1.08
Diesel Smoke 14 63.64 2.64 1.22
Oil Fumes 14 63.64 2.29 1.20
Welding Fumes 11 52.38 2.09 0.94
Asbestos 11 57.89 3.18 0.98
Solvents 19 90.48 3.53 0.77
Epoxy 19 90.48 2.84 1.01
Sulfa-set 6 33.33 1.50 0.84
Grout 9 47.37 2.11 1.05
Solvents - Skin 21 95.45 3.29 4.01
Epoxy - Skin 18 81.82 2.83 1.04
Sulfa-set - Skin 5 31.25 1.80 0.84
Grout - Skin i) 47.37 1.89 0.93
Beryllium 1 7.14 3.00
IGAN
Loud Noise 122 96.83 2.84 0.92
Vibration 98 79.67 2.34 0.98
Shotcrete 84 71.79 2.01 0.84
Rock Dust 106 84.80 2.26 0.91
Diesel Smoke 114 90.48 2.35 0.89
Oil Fumes 95 76.61 2.11 0.96
Welding Fumes 100 80.00 2.19 0.86
Asbestos 66 $7.39 1.85 1.03
Solvents 73 60.33 1.96 0.98
Epoxy 65 55.08 1,82 0.95
Sulfa-set 58 50.43 1.83 0.92
Grout 89 71.77 2.20 0.87
Solvents - Skin 43 35.25 1.67 0.99
Epoxy - Skin 35 28.93 1.37 0.77
Sulfa-set - Skin 33 27.50 1.42 0.79
Grout - Skin 51 41.13 1.63 0.82
Beryllium 42 48.28 1,95 0.94

Other



NTS Review of Medical Surveillance Questionnaire Data and available Dosimetry
Data

1.0 Project Description

The uncertainty surrounding radiation exposure information for construction workers is a
great challenge in terms of completing dose reconstruction for individual workers as
required in the Energy Employees Occupational Illness Compensation Program

Act (EEOICPA). This project proposed to review findings from former worker medical
surveillance programs regarding work and site history information and determine if any
of the information could be useful in former worker dose reconstruction efforts.

2.0 Study Aims

This study included four primary tasks: 1) Perform a detailed analysis of work history
questionnaire used during the medical surveillance program, 2) perform an assessment of
work history variables as predictors of radiation dose, and 3) perform a review of
available electronic dosimetry databases for completeness and validity of data, and 4)
review a small sample (20 case files) of NTS in-depth dose reconstruction hard copy case
files.

3.0___ Overview of Site and Cohort of Interest

3.1 Site Description

During 41 years of operation from 1951 through 1992 there were 828 underground
nuclear tests and 100 above ground tests. Of the 828 underground tests, 67 were Tunnel
tests, 765 drill-hole tests and 9 crater tests (DOE, 1994), The drill-hole tests were fired
several hundred meters below ground surface. The drill hole tests were fielded primarily
for the purposes of developing new weapons systems. The NTS drill hole tests were
conducted beneath Yucca Flat (Areas 1,2,3,4,6,7,8,9, and 10) and Frenchman Flat (Areas
5 and 11) for lower yield experiments, and beneath Pahute Mesa (Areas 19 and 20) for
higher yield experiments. Horizontal tunnel tests occurred within tunnel complexes
excavated in Rainier and Aqueduct Mesas (Area 12), Oak Spring/Butte (Area 15), and
Shoshone Mountain (Area 16). (Smith, DK 2003)

At the peak of underground testing in the mid-1980's as many as 15,000 workers were
employed at the Site, about one-third of them construction workers. Digging,
maintaining and re-entering the tunnels and shafts used for nuclear testing at the Nevada
Test Site was the daily work principally of six unions: Laborers Loca! 872, (Tunnel
Workers), Operating Engineers Local 12, Electrical Workers Local 357, Plumbers and
Pipefitters Local 525, Ironworkers Locals 416 and 433, and the Carpenters Local 1780,
who together represented as many as 5000 Test Site workers at the peak of Test Site
activity.



the year of 1961, 1962, or 1968 and annual summary data for periods from 1963-1967 and 1970-
1971. All other time periods indicate regular data. External dosimetry database includes
monitoring data for the entire time period and the data is consistent with the hard copy record.

Case 9:

Individual indicated he worked from 1964 through 2000. Full case file indicates external
dosimetry data for the time period from 1965 through 2000. The hard copy records indicate a
date only for several of the dose entries for the time period from 1967 through 1970 with the
dose hand written over the computer printout as zero. The years for which the computer
printout had no data the hard copy file included card-punch data and the values were added to the
printout based on the card punch data. It does not appear that the computer printout for other
years was validated against the card-punch data. Extensive tritium sampling data appears to be
consistent when comparing the hard copy records against the database records. Database records
indicate one Pu-238 sample in 1970 but the hard copy record indicates an I-131 exposure that
year with a thyroid dose assigned (this may simply be an error in the database field code). Hard
copy record indicates a whole body dose assigned from a Ruthenium exposure in 1971 but the
database does not include any sampling for that time period. Finally, the database and hard copy
records indicate alpha smear samples in 1962 with no results and no dose assigned. The
calculated tritium doses were reviewed using the same assumptions as the NTS staff used and
using CINDY version 1.4 with ICRP 30 tritium model and doses consistent with the reported
doses were obtained..

Case 10:

Individual indicated he worked form 1963 through 1996. Full case file indicates external
dosimetry data for the time period from 1963 through 1995 with annual summary data only for
1963, 1964, and 1967 and no data for 1966, 1970, and 1971. All other years included regular
data. External dosimetry database includes no monitoring data for the time period from 1963-
1992. Neither hard copy records or database records indicate any bioassay sampling.

Case 11:

Individual indicated he worked from 1961-1993. Full case file indicated no records for 1961-
1962, annual summary record for 1963, regular records for 1964, annual summary record for
1965-1971, and regular records for 1972 through 1993. External dosimetry database indicates no
records for 1961-1993. Hard copy records indicate 24 tritium samples for the period from 1981-
1991 with no dose assigned (results were very low). Hard copy records indicated Pu-239
samples for 1982-1986 and 1991 with no dose assigned. Database indicated no bioassay data.
The calculated tritium doses were reviewed using the same assumptions as the NTS staff used
and using CINDY version 1.4 with ICRP 30 tritium model and doses consistent with the reported
doses were obtained..

Case 12:


Post-Shot Los Pipe -

Mining in Shafts

instrument Alcoves in Tunnels n=228
Yes 168 73.68
No 60 26.32
Post-Shot LOS Pipe - Cut / Disassembled LOS Pipe in
Tunnels n=399
Yes 142 35.59
No 257 64.41
Post-Shot LOS Pipe - Disposed of LOS Pipe / Contents in
[Tunnels n=405
Yes 193 47.65
No 212 52.35
Number of Post-Shot LOS Pipe Entries in Tunnels n=487
0 113 23.2
1-10 217 44.56
11-20 49 10.06
21-30 27 5.54
31-40 13 2.67
>40 68 13.96
"Other" Work in Tunnels n=1725
Performed 600 34.78
Present 34 1.97
Neither 1091 63.25
Ever Worked in Shafts n=2741
Yes 1189 43.38
No 1552 56.62
Number of Shafts Worked On: n=1143
0 35 3.06
1-10 937 81.98
11-20 93 8.14
21-30 25 2.19
31-40 11 0.96
>40 42 3.67
‘Number of Shafts for Which Performed Re-entry Work
1or more 590 55.04
n=641



If yes, how many,

times? n=275
1 132 48 5.12 15.82
2 69 25.09
3 24 8.73
4 17 6.18
5 9 3.27
6 2 0.73
8 4 1.45
9 1 0.36
10 3 1,09
412 1 0.36
20 3 1.09
25 1 0.36
30 1 0.36
50 1 0.36
99 7 2.55
Were you ever sent
home because you
were near or above
the radiation limits? n=2739
L Yes 131 4.78
No 2608 95.22
If yes, how many’
times? n=112
1 53 47.32 5.08 15.94
2 29 25.89
3 10 8.93
4 4 3.57
5 6 §.36
6 1 0.89
8 4 0.89
10 2 1.79
11 4 0.89
20 2 1.79
99 3 2.68
Did you wear a
radiation badge /
dosimeter when you
worked at NTS7 n=396
Yes 382 96.46
No 14 3.54



Number of Workers - Ali Trades

400

300 ¥

200

100 §

Age Distribution of Screened NTS Workers
n=2753

45-49 §0-54 55-59 60-64

Age Category at Time of Screening

70+



3. It appears that the NTS electronic database may not be very useful in considering
worst case estimates since it appears to have fairly extensive data gaps and the
bioassay data within the database clearly needs to be validated and verified prior
to use.

4. Itis apparent that the use of co-worker data for estimation of missing data will
have to be very specific (for instance data of a co-worker during a given event
could possibly be useful for estimating missing data) since the work performed by
these construction workers varied greatly and the areas they worked and the type
of work that they did between events seems to have varied greatly.

5. Caution should be exercised in using area-monitoring data for determining
internal doses since it was apparent that bioassay findings from the E-tunnel
decontamination work were inconsistent with the area monitoring data (Skrable,
1995), Further, Skrable concluded that the area air sampling results were not
representative of the workers exposures and that they received their major
exposure by creating airborne activity through their own work.

6.0__ Preliminary Assessment of the NTS dosimetry database against hard copy

records

As part of the task of determining whether there were data gaps and the extent of the data
gaps we obtained several radiological safety reports (primarily from different events)
from 1957 through 1988. In reports that included summary radiation exposure
information in a format that could be easily compared with the electronic data, we
attempted to cross walk the hard copy summary records against the database information.

Preliminary analysis of the database records compared with available radiological safety

reports suggests possible missing information in the electronic records. This suggests
that further validation and verification of database information against original records is

needed.

Some examples of possible discrepancies between radiological safety report data and
database records include the following:

> Comparison of a 1957 Radiological Safety summary report (REECO 1957) with
the NTS dosimetry database suggests discrepancies in the cumulative gamma
doses. The table below shows a summary of these results:

Gamma Dose Personnel (57 Rpt) Personnel (NTS dbase)
(mrem)

) 4,724 252

1-99 1,794 184

100-499 1,895 275

500-999 690 100

1,000-4,999 1,015 268

> 5,000 22 32



Ironworkers: Cumm Gamma Dose vs. Years
Worked (first worked 1980s)

1-5 yrs 6-10 yrs 10-20 yrs >20 yrs
Years Worked



Piumbers/Pipefitters: Cumm Gamma Dose vs.
Years Worked (first worked 1960s)

400
350
300 4
250
200 |
150
100
50 |

M Series1

<1 1-5yrs 6-10 yrs 10-20 yrs
Years Worked

>20 yrs



Individual indicated he worked from 1962-1998. Full case file indicated regular records from
1962 through 9/12/95 with the exception of 1994 (no records for that year). Annual summary
records only for 1963-1971 and regular records for 1972-1995. External dosimetry database
indicates records consistent with hard copy records. Hard copy and database indicated one
whole body scan with no dose assigned.

Case 13:

Individual indicated that he worked from 1968 through 1991. Full case file indicated annual
summary records for 1968 through 1970 and regular records from 1971 through 1991. External
dosimetry database indicates no records for period between 1963-1991. Hard copy indicates
two whole body scans and database indicates one whole body scan. Hard copy records show no
internal dose assigned.

Case 14:

Individual indicated that he worked from 1981 through 1994. Full case file indicated regular
records from 1981 through 1994. External dosimetry database indicates no records from 1981-
1994. Hard copy records indicate tritium sampling in 1984 and 1986-1988 and 1990 and 1992
with dose assigned only in 1986 since other calculated doses were less than 10 mrem CEDE.
Database indicates only 1 tritium bioassay sample. The calculated tritium doses were reviewed
using the same assumptions as the NTS staff used and using CINDY version 1.4 with ICRP 30
tritium model and doses consistent with the reported doses were obtained..

Case 15:

Individual indicated that he worked from 1961-1993. Full case file indicated regular records
from 1961-1994. External dosimetry database indicates annual summary records for 1961-1971
and regular records from 1972-1992. Hard copy records indicate 17 tritium samples from 1962-
1963, 17 samples from 1966-1971, and 35 samples from 1972-1984. Database indicates 17
samples from 1962-1963 and 18 samples from 1972-1984. No samples from 1966 through 1971.
Whole body dose from tritium exposures was assigned for 1962, 1963, 1967, 1971, and 1972.
The calculated tritium doses were reviewed using the same assumptions as the NTS staff used
and using CINDY version 1.4 with ICRP 30 tritium model and doses consistent with the reported
doses were obtained..

Case 16:

Individual indicated that he worked from 1951-1991. Full case file indicated regular records for
1951, no records for 1952-1958, annual summary record for 1959, no records for 1960-1963,


Case 20:

Individual indicated that he worked from 1955-1957 and again from 1967 through 1994. Full
case file records indicate regular records for 1957-1959, no records 1960-1964, annual summary
record for 1965, no records for 1966-1967, regular records for 1968, annual summary records for
1969-1971, regular records for 1972-1979, no records for 1980-1987, and regular records for
1988-1994. External dosimetry database indicates regular records from 1957-1958, annual
summary for 1959, annual summary records from 1965-1971 and regular records from 1972-
1979, and regular records from 1988-1992. Hard copy records and database records indicate 2
alpha nasal smears in 1957 with no dose assigned.


thyroid dose in the 10’s of rads with no iodine sampling in the electronic database, cases
where apparently I-131 was miscoded and appeared to be Pu-238 in the electronic
database, etc.). A sample of the tritium dose calculations was reviewed and
independently calculated doses were in agreement (using same assumptions as NTS staff
used). For the tritium dose calculations the work history was not often verified to
determine whether assumptions regarding the nature of the exposure were appropriate
(acute or chronic) however, it appears that given the small overall doses conservative
assumptions were made. This may be more problematic with radionuclides of greater
dose consequence.

A number of the cases reviewed had hard copy data and dose estimates for a plutonium
intake in 1994 (this data was not in the database but the electronic database only included
data through 1993). These cases all seem to be related to the same event at the E-Tunnel
and the dose calculations included in the case files referenced an outside consultant report
(Skrable, 1995 ). One question this report raises is the effectiveness of the NTS urine
monitoring program and the potential for un-detected doses from plutonium exposures. It
also notes that for this specific job (E-Tunnel decontamination) it appears that using
Cesium-137 measurements from area air sampling as a surrogate measure for plutonium
levels (based on a ratio established from soil sampling data) was not an effective way of
controlling exposures since there were workers with significant doses even though the
area air sampling action levels were not exceeded. This question should further be
considered for the historic data (1960s) where there are a great deal of alpha nose wipes
which were collected and were determined to be less than detectable and for which no
dose was assigned.

Other important discrepancies that we feel are worth noting and may be of importance to
the efforts underway for dose reconstruction at the NTS site are outlined below. A
detailed account of each case is included in Appendix B (Case File Results Review).

Some important points:

1. For many of the years included in the dosimetry database the data is only
summary data (usually annual summations). This especially appears to be the case
for 1961-1971.

2. Seven of the twenty case files reviewed have no records prior to 1965. Their
work history questionnaires indicate that they were working on site prior to 1965.
The discrepancy could indicate missing data for the early years or it could be that
these individuals were not in areas requiring monitoring in those early years of
their careers or that they misreported their initial hire date.

3. Data related to internal dose had more discrepancies including the following:
differences in the data with regard to tritium sampling, one instance where a
thyroid dose was assigned but there was no data in the database, a possible
discrepancy in the ‘analysis type’ field in the database where some samples
appear to be coded with an incorrect code (coded for Pu-238 when the hard copy
records indicate no exposure to Pu-238 but rather to I-131), and finally some