Working Draft 

A PAPER STUDY OF THE SEC PETITION AND NIOSH 

EVALUATION REPORT FOR PANTEX 

Revision 1 

Contract 200-2009-28555 

Prepared by 

S. Cohen & Associates 

1608 Spring Hill Road, Suite 400 

Vienna, Virginia 22182 

Saliant, Inc. 

5579 Catholic Church Road 

Jefferson, Maryland 21755 

March 2009 

The attached “Pantex Plant SEC Issues Matrix – Draft Preliminary SC&A Assessment” is a 

revision of the document, A Paper Study of the SEC Petition and NIOSH Evaluation Report for 

Pantex, issued on December 9, 2008. It reflects some non-technical streamlining and reordering 

of issues to improve the structure of the matrix in preparation for work group deliberations.

Disclaimer 

This document is made available in accordance with the unanimous desire of the Advisory Board on 

Radiation and Worker Health (ABRWH) to maintain all possible openness in its deliberations. However, 

the ABRWH and its contractor, SC&A, caution the reader that at the time of its release, this report is predecisional and has not been reviewed by the Board for factual accuracy or applicability within the 

requirements of 42 CFR 82. This implies that once reviewed by the ABRWH, the Board’s position may 

differ from the report’s conclusions. Thus, the reader should be cautioned that this report is for 

information only and that premature interpretations regarding its conclusions are unwarranted.
Draft Response to NIOSH ER Report – Rev. 1 2 

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1 Adequacy of Internal 

Dose Records 

• During essentially all years under evaluation, there was no 

Pantex bioassay program for uranium, thorium, or plutonium that would be considered “routine.” Instead, bioassay was performed for specific events and for known or suspected exposure incidents. 

• According to both procedures and interviewed employees, 

evidence of potential exposures was always followed by 

additional area monitoring/media sampling (as appropriate), and also included personnel bioassay monitoring (if deemed necessary). 

• The routine bioassay program for radionuclides other than 

tritium was short-lived, occurring mostly in 1991 and 1992. 

Research did not reveal the level of air concentrations or other workplace indicators that triggered special bioassays before 

1991. 

• Except for a single measurement made for Pu-239 and Am-241 

at the Los Alamos Scientific Laboratory in 1978, no records of 

in-vivo measurements made within the 1951 through 1991 evaluation period are available. 

• More than 200 personnel working on a disassembly program 

were monitored by the Helgesen in-vivo counter in 1989; however, the results of the in-vivo counts were later determined to contain a positive bias and were deemed not credible (Helgeson 1989). 

• While the quantity of Pantex internal data collected during the 

proposed class time is relatively low, it is consistent with the internal exposure potential associated with work conducted at the Pantex Plant (pg. 35). 

• Data available for estimating internal doses due to potential 

(1) Although the presence o

has existed since 1952, to incident-based samploperating period in quesfor tritium was initiated few samples prior to thabioassay began to a minrespectively. No routinfor worker intakes prior data exists for some isono documented trigger lwork practices, and the the 40 years in question extrapolation or boundiNIOSH has not demonsmore current data for thtime. 

(2) The ER’s reliance on as

procedures and employebasis to assume positive understood “cleanlinessperformed do not providoverriding the wide gapapplication of generalizdisparate documents thaeither time or place, and question, is neither techaccurate. 

(3) Pantex did not have a lu

measurements of pluton

the lungs of workers. Tfecal monitoring prograbe given to the inherent potential acute and chro

 has been redacted as of February 3, 2010. Note, however, that 

issues matrix will not be freely distributed to the public until further reviews for Privacy Act-protected information are 
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uranium, plutonium, and thorium exposures are predominantly from sampling/analyses performed in 1989 or later (pg. 36). 

• Hardcopy air monitoring results applicable to specific activities 

have been documented and are available to NIOSH (see 

Attachment One of the ER). 

• Based on the available data and the re-evaluation of the 

hundreds of documents in the SRDB related to Pantex, specifically in the area of internal dose, NIOSH concludes that 

the methods described in ORAUT-TKBS-0013-5 provide reasonable approaches to conservatively bound doses for all members of the class under evaluation. New information revealed since the TBD was issued confirms that internal dose assessment was performed on an appropriate, as-needed basis. As proven based on the available program documentation, the Pantex Plant operations were performed under strict radiological cleanliness controls and continually performed workplace monitoring to determine whether contaminated weapons were brought onsite or in the case of an inadvertent release of radioactive materials. 

plutonium, americium, addition, the Tiger Team 

to 1989, the plant was nsampling (DOE 1990). 

(4) Few air sampling record

as the explosive cell, an

1963, 1973, 1978, and 1available for only 1989 sampling is also availabair-sampling data for thfor a limited number of in the ER are used acropreponderance of data iwhich may not be reprebreathing zone. When urecommends applying a plutonium) for the uppedistribution to account fsampling system is not breathing zone. There iair monitoring equipmeand the employees. An may be too low for such of the air monitoring prits appropriateness for u

2 Internal Dose Models 

for the Assignment of 

Internal Dose from Uranium 

• The only nuclear component involved at Pantex prior to 1957 

was DU. Because DU components were new at the time of 

assembly, there was minimal potential for DU oxide contamination (pg. 22). 

• All of the unsealed uranium used at the Pantex facility was 

either DU or natural uranium. Enriched uranium was always associated with a sealed component with little likelihood of 

(1) The ER uses unsupporte

exposures and makes insampling detection limiexposures. The internaunmonitored workers (1and not claimant favoraPantex are very limited 1993, NIOSH elected to that was derived from a 

 has been redacted as of February 3, 2010. Note, however, that 

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release and, therefore, not considered a significant potential exposure source for the proposed worker class evaluated (pg. 22). 

• Some DU was also released at the hydrotest firing sites when 

hydroshots involved DU (pg. 23). 

• No bioassay data were found for Pantex workers involved in the 

burning of DU-contaminated high explosives and hydroshots; however, the doses can be adequately bounded by doses calculated from air-sampling data (pg. 39). 

• The DU intake data related to the contamination incident in 

February 1989 can be used for bounding the potential uranium doses for assembly/disassembly workers. Isotopic determination of uranium alpha activity in urine samples is available and the data set contains sufficient data to perform statistical analysis (pg. 39). 

• Internal doses are calculated based on methods outlined in 

ORAUT-TKBS-0013-5 (Hickey et al. 2007, pp. 41–42). 

1989. The ER and TBD information that charact

incident” in terms of veworkers in fact represenradiation safety technicipersonnel who, moreov10-year period, as assumquestions the basis of thworkers over Pantex’s ofrom the 305 workers m

(2) Significant quantities of 

ER recognizes that plut

form and assigns a poteEU presents the same phas not addressed poten

(3) The TBD contains unex

changes in sensitivity vminimum detectable actsignificant data gaps. Tshows an apparent impr2 orders of magnitude bthen diminishes by a facGaps also appear in the information on sensitivi

and 1983–1990. With twide variations in valueor the TBD provides a tapplying uranium bioasapplications and intake and years. 

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3 Dose Estimate 

Approach for 

Plutonium 

• Bounding doses from plutonium can be calculated for Pantex 

employees. 

(1) For the period from 1958 (the year that plutonium was 

introduced to Pantex) to 1991 (except 1961, as discussed 

below), air-sample levels that would have triggered bioassay are not known; however, fewer disassemblies occurred and the plutonium was newer, meaning that there was less potential for oxidation and, therefore, personnel exposures to plutonium. Assemblies would have involved newly sealed plutonium metal. Consequently, the possibility of intakes and the severity of intakes would have been less. However, because the documentation of the number of disassemblies and the contamination levels are not available, unmonitored workers may be assigned an intake that is the same as the intake from the 1991 to 2000 period. (This excludes workers involved in the 1961 Cell Incident, which have a separate bounding dose.) 

(2) Because intakes were rare for the period 1991 to 2000 

(1991 for the evaluated class), the criterion for investigation of possible acute intake (including obtaining special bioassay) can be used to support establishing bounding intake estimates for the proposed worker class evaluated in this report. During this period, when the number of disassemblies was highest and the plutonium was oldest, the criterion for investigation was any workplace indicator, indicating that an intake of 40 DAC-hours (290 pCi) might have occurred. These intakes can be assigned to the workers with the highest exposure potential as the mode of a triangular distribution with a minimum of 0 and a maximum of 10 times the mode. The factor of 10 for the upper limit of the distribution is set to account for the possibility of more than 1 intake per year and the possibility that the air-sampling system is not representative. The 

The ER assumes a single acuyear, based on the investigat

2000, and applies the internaplutonium outlined in the inare assigned to the workers wmode of a triangular distribumaximum of 10 times the mintake assumes that workplaadequate personal monitorinexposure conditions to the wfor this assumption. The usexposure recommended by t100 mrem total effective dohave been detectable, and is findings and investigation reworkers as late as 2000, with monitoring capabilities takethat had in fact been monitocriterion (but for whom no rof 40 DAC-hours may only threshold value. The ER andemonstrated that this appro

Draft Response to NIOSH ER Report – Rev. 1 5 

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issues matrix will not be freely distributed to the public until further reviews for Privacy Act-protected information are 
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bounding intake for the period from 1991 through 2000, therefore, is 400 DAC-hr (2,900 pCi acute intake) per year of employment for high-risk tasks. 

• Plutonium at Pantex was in the form of encapsulated pits of 

nuclear weapons. Strict workplace monitoring practices, 

including smears for contamination, were completed during assembly and disassembly to ensure the integrity of the encapsulation (pg. 23). 

• Internal doses are calculated based on methods outlined in 

ORAUT-TKBS-0013-5. 

4 Dose Estimate 

Approach for Thorium 

• Workers handled thorium compounds during assembly and 

disassembly of certain weapons. Pantex used strict workplace 

monitoring practices, including smears for contamination on components to verify the encapsulation of the thorium (pg. 24). 

• It is assumed that workers could have encountered oxidized 

thorium components during disassembly of weapons in the mid1960s (pg. 24). 

• Bounding doses from thorium can be evaluated for Pantex 

employees (pg. 40). 

• From 1980 to present, the methods for assigning intakes of 

thorium are the same as for plutonium because of similar workplace conditions. Specifically, there were fewer disassemblies containing thorium; thus, the plutonium methods are claimant favorable for thorium....For workers who had the highest possibility of intake for each year from 1980 to 1991, a single acute intake of 40 DAC-hrs (48 pCi) of Th-232 (in equilibrium with progeny) was assumed. For Category 2 workers in Table 5-2 of the ORAUT-TKBS-0013-5, 0.1 times the intake was assigned. These intakes are modes of triangular distributions with a minimum of 0 and a maximum of 10 times 

(1) NIOSH has not provide

monitoring practices vethorium. Furthermore, have encountered oxidizfact, confirmed the existhorium-bearing weapo

(2) For thorium, the assump

unmonitored thorium winconsistent with the argDU workers during disaincidents of thorium conthe 1960s, although the types of workers are sim

(3) For the era prior to 1980

uptake the same as the bmass basis (i.e., 5.2 pCisimilar behavior of thorworkplace. There has brelative quantity of matER and supporting docuthis approach bounds th

Draft Response to NIOSH ER Report – Rev. 1 6 

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issues matrix will not be freely distributed to the public until further reviews for Privacy Act-protected information are 
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the mode to account for the possibility of more than 1 intake per year and the possibility that the air-sampling system is not 

representative (Hickey et al. 2007). 

• The ER proposes a methodology for assessing a bounding dose 

for thorium using uranium data for time periods before 1980. 

Because DU contamination and thorium contamination would have been in the oxide form and behaved similarly in the workplace on a mass basis, it was assumed that the bounding intakes for inhalation of Type S and insoluble ingestion of thorium were the same as the bounding intakes for DU on a mass basis (pg. 44). 

• Internal doses are calculated based on methods outlined in 

ORAUT-TKBS-0013-5 (Hickey et al. 2007). 

(4) From 1980 to the presen

is assigned for thorium-

intake assumes that worof adequate personal mothe exposure conditions basis for this assumptioannual exposure recommto 100 mrem TEDE, maworkers that had in fact 40 DAC-hour criterion the assigned value of 40 lower bound or thresholdocuments have not dembounds the thorium dos

5 The Internal Dose 

Approach for Metal 

Tritides 

• Tritides were formed as a result of tritium gas reacting with 

metal components of weapons and producing tritiated compounds. In addition, tritium compounds were used in some weapons programs (pg. 23). 

• A Cockcroft Walton neutron generator also produced some 

tritium in the off-gas and tritium particulate contamination 

existed in the target and the area where the target connected (pg. 23). 

• The assessment of metal tritides revealed that the doses would 

not impact the bounding dose established for tritium in ORAUT-TKBS-0013-5 (Hickey et. al. 2007) (ER, pg. 42). 

In interviews conducted by S

reviewed, some of the Pantewere present in some of the Metal Tritides—Technical B2004), addressed some of thtritides and the disassembly metal tritides present. Eleminteract with metals and orgtritium compounds. In addiworkers directly to metal tritritides would not impact the because it constitutes such a 

workplace. However, no foER of the types of tritium corelative concentrations. Comand other insoluble forms of have substantially longer restherefore, provide a higher delemental tritium or tritiated typically implemented for so

 has been redacted as of February 3, 2010. Note, however, that 

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not work for insoluble comptritides handled at Pantex. 

Interpretation of 

External Dosimetry 

Data 

• The nature of the radiation fields a worker could have 

encountered depends on the type of facility in which the work 

occurred. Nuclear weapons components emit alpha, beta, x-ray, gamma rays, and neutrons; however, dose to workers depends strongly on the configuration (i.e., material and shielding) of the source radiation and work performed (pg. 24). 

• Industrial radiography operations had the potential to exposure 

some workers to x-ray, gamma, and neutron radiation (pg. 24). 

• Am-241 was an increasingly significant source of exposure to 

workers performing weapons disassembly, which often occurred many years after assembly (pg. 25). 

(1) Early recorded deep dos

is clear that for proper a

calibration curves must energies of the work enenergy for Pantex workassociated with Am-241than the calibration phoCs-137, which had been The use of Cs-137 or Cthe dominant workplace lead to an over-responsresult of photographic fwith Z values of 47 and response for the deep attenuation effects of 1,squared (mg/cm2) (or 0

which has a Z value of 

(2) Calibration and dosimet

contractor services cann

information. Three conbetween 1952 and 1973 While the competency oit is without basis to assthat each would have usthat matched the expectwork environments. Gienergies to which workthe highly classified natreasonable to question wcan be expected to have to apply to individual P

Draft Response to NIOSH ER Report – Rev. 1 8 

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(3) Exposures from skin co

weapons programs invo

exposure from this routcancers. The current mbody penetrating dose idose is unavailable may particularly in situation

(4) Derived estimates of the 

unmonitored workers arworker photon dose statTBD (Fix et al. 2007), arecords for monitored wequal to or greater than For the 10-year period oexchanged weekly, whithe period 1952–1958, amonitored workers) werthe basis of these statistworkers would also not neutron doses for the yeto the present, the excluderiving the median dosimpact the estimated doSC&A does not considereconstruction of unmonfavorable. For deriving unmonitored workers, mworkers should be inclu

7 Data does Not Support 

the Assumption that the 

95th Percentile Neutronto-Photon Ratio is 

Bounding for All Exposure Scenarios 

The ER (pg. 26 states) states the following: 

The TBD neutron-to-photon ratios are based on worker dosimeter measurements that were recorded using the 

Panasonic UD-809/UD-812 system and correspond to doses in which both the photon and neutron doses of the individual exceeded 50 mrem per year. From these data, a 

While the recommended neubound some of the Pantex w

assured that it will bound all 1951–1992, because of the f(a) Back-extrapolating to supported. The n/p value o

 has been redacted as of February 3, 2010. Note, however, that 

issues matrix will not be freely distributed to the public until further reviews for Privacy Act-protected information are 
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median neutron-to-photon ratio of 0.8 and a 95th percentile 

value of 1.7 were calculated. For dose reconstruction of monitored workers, NIOSH recommends the 95th percentile 

neutron-to-photon ratio of 1.7. 

The ER (pg. 47) states the following: 

Neutron doses measured at Pantex since this time [1993] with this new system are considered reliable for use in this 

radiological dose reconstruction program, and these measurements provide a basis for using neutron-to-photon dose ratios to permit estimating worker neutron doses for the periods prior to the accreditation. Based on NIOSH’s review and evaluation of the weapons systems handled at Pantex, and the assembly of the list that permits comparison across all times associated with this evaluation, NIOSH is able to establish that the neutron-to-photon dose ratios, applied to bounding photon doses, result in calculated neutron doses that are considered bounding across all time periods. The method used to bound neutron doses is addressed in Section 7.3.4. 

Section 7.3.4 of the ER (pg. 50) states the following: 

Photon doses (with appropriate corrections for lead apron use and dosimeter response uncertainty) were reliably measured 

from 1994 forward and can be used with a neutron-to-photon dose ratio of 1.7 to calculate neutron doses for the years prior to 1994 (ORAUT-TKBS-0013-6; Strom unknown date). The average neutron-to-photon dose ratio determined from reliable collective neutron and photon doses measured since 1994 is only 0.25 (see Table 6.1 in ORAUT-TKBS-0013-6). Thus, this method for calculating neutron doses prior to 1994 will result in average neutron doses to workers that are approximately 6.8 times the expected doses, which will be bounding (ORAUT-TKBS-0013-6) for the class evaluated in 

43 data points taken during tno supporting evidence that 

radiation fields were sufficiethe previous 42-year period, measurements would have trelationship. NTA film resupurpose, because they have (b) Examples where n/p of numerous examples over a s1995) that indicates that usinof 1.7 would not bound the n

for some examples where thranged from 2.0 to 13.6, witduring surveys. Additionallfilm results show a dose greneutron-to-photon ratio valubecause the correct neutron film results, which have beereconstruction cases have usranging from 0.25 to 2.5. (c) Comparison to collectivalue not valid. The statem

neutron-to-photon ratio valuto-photon ratio value of 0.25 not a valid comparison, becadose was from workers who the results were diluted by p0013-6, pp. 33 and 56). (d) Reliability of recorded While SC&A agrees that the external dose records at Panquestion whether the measurreliable for use in assigning 

 has been redacted as of February 3, 2010. Note, however, that 

issues matrix will not be freely distributed to the public until further reviews for Privacy Act-protected information are 
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this report. 

Typically, there should not be a significant neutron exposure to unmonitored workers. However, for an unmonitored worker with 

some evidence of potential neutron exposure, neutron doses can be estimated by applying a median neutron-to-photon dose ratio of 0.8, as determined by the log probability analysis of grouped Pantex and neutron dosimeter data (Strom, unknown date). This median value, when applied to the assigned photon dose for monitored workers, will yield a bounding neutron dose to unmonitored workers. ER pages 46 states 

Since first used, the film badges and TLDs assigned at Pantex 

have been capable of measuring photon exposures in the 

workplace with sufficient accuracy to permit the calculation of bounding photon exposures. There is strong evidence that workers who had the highest potential for radiation exposure were monitored with state-of-the-art dosimeters (National Bureau of Standards 1955) and the measured photon doses were reasonably accurate and complete (ORAUT-TKBS-0013-6). Dosimetry records maintained by the Radiation Safety Department have been independently reviewed by the HERS project to verify accuracy and to ensure complete documentation (Rawlston 1991).

. The ER (pg. 50) states that an alternate method has been developed 

for conservatively estimating missed neutron doses. Neutron and gamma dose rates associated with various weapons configurations are available for LANL and LLNL-designed nuclear weapons handled at Pantex. Dose rate data for individual weapons have been located at Pantex to cover the weapons configurations encountered during assembly and disassembly operations. The dose rate data, coupled with the exposure times derived from time and motion studies of the nuclear explosive operations, allow the calculation of exposure time-weighted neutron-to-photon dose ratios. Using the 

doses, while relying on only photon dose. An error in ph

magnified by a factor of 2.7 photon ratio = 2.7 total errorfollowing areas of concern, elsewhere in this matrix and calculations: 

• Calibrated using med

(Co-60 and Cs-137)

60 keV 

• Early photon dosime

over-response, must 

• Wide range of photo• Three different dosim

to classified photon 

• Pantex TBD and SE

correct, while IAAPonly 37% of 60 keV 

• DOE investigation b

credibility of photonreconstruction at Pan

 has been redacted as of February 3, 2010. Note, however, that 

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neutron-to-photon dose ratios, the missed neutron doses can be estimated based on the measured photon doses and assigned to the 

personnel performing the nuclear explosive operations. These data allow determination of bounding neutron doses. 

8. Completeness and 

Interpretation of 

Historic Radiological Exposure Sources 

(1) The primary sources of internal radiation contamination have 

been depleted uranium oxide and tritium. The primary sources 

of external radiation exposure include plutonium pits and depleted uranium or thorium components (Personal Communication October 1, 2003). 

(2) The burning grounds were used to burn high explosive (HE) 

waste, some of which was contaminated with uranium. 

• Data that did not indicate contamination and/or exposures 

(“negative” data) were often not saved for future reference, particularly in the earliest years of operations (Personal Communication April 8, 2008). This Pantex recordkeeping practice, coupled with the relative cleanliness of the materials and work performed at Pantex, and the site’s practice of only collecting bioassay samples when other monitoring/events dictated a need, has resulted in apparent monitoring data gaps for many types of internal monitoring data over the years (pg. 29). 

• Exposure records from previous employment at other sites were 

also collected and incorporated into workers’ exposure files, as were exposures while employed at Pantex (pg. 35). 

(1) There is a need to chara

exposure associated wit

time periods, including development technologand the potential for intquestion (1951–1991). to internal contaminatiorisk to disassembly and 

(2) The predominant source 

the assembly, disassembwhere radioactive materclose to the body. The energy with the differengenerating devices usedare few gamma and neuprior to the mid-1970s. 

(3) The basis for determinin

burning activities was aof 1960-1967. The defaburning ground was 130 air-sampling data were (Hickey et al. 2007). (SArea exposures for furth

(4) The ER indicates that in

result of the relative clePantex, and the site’s prsamples based on field isite expert interviews coprofile review indicate r

 has been redacted as of February 3, 2010. Note, however, that 

issues matrix will not be freely distributed to the public until further reviews for Privacy Act-protected information are 
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significant oxidation of related to particular pro

containing negative expnot retained. In light of workers, actual field mocharacterizing and ascerinternal exposure. 

(5) Pantex workers were in

as the Tweezer Project 

weapons accident recovweapons. The ER does exposure from these offconducted by Pantex emand evaluated debris anassembly operations anextramural work potentdifferent source terms wworking with damaged from these activities is n

9. Incidents Discussed in 

the ER and TBDs are 

Limited 

• To support the incident/suspected exposure-driven internal 

monitoring program, all aspects of work at Pantex have always 

involved procedures and routine contamination checks (e.g., smears, air sampling) to assist in identifying work locations with potential for internal exposure (pg. 28). 

• Documented monitoring data obtained from response work is 

available for bounding the doses associated with incidents that occurred during the evaluation period (pg. 27). 

• A list of Pantex incident/accident report titles applicable to the 

NIOSH evaluated time frame have been reviewed by NIOSH (pg. 26). 

(1) The ER does not suffic

exposures. These incid

the bioassay program pinformation on what dewere formally communto the personnel involvexposure records. SC&radiological incidents nand for which the persodata. The internal dose plutonium and thorium should be assumed. Exare usually the result ocontinuous exposures. resulting in exposure to 

 has been redacted as of February 3, 2010. Note, however, that 

issues matrix will not be freely distributed to the public until further reviews for Privacy Act-protected information are 
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reconstructor of potentFurthermore, the moni

to cleanup workers frocarefully evaluated to dadequacy of monitorin

(2) The ER assumes all ind

were monitored; howeincidents by current staconsidered routine in s

10 Adequate Consideration 

has not been given to 

the Potential Exposures at the Firing Sites 

The summary of the dose assessment methodology for the firing sites is outlined in the ER. A bounding intake can be determined 

using air-sampling results and additional assumptions. Because the employees at the firing sites were likely different than the assembly/disassembly workers, a separate bounding dose appropriate is provided for these workers (pg. 42). 

Hydroshots were conducted 

surrogate material resulting firing sites. Significant quanshots during the late 1960s a83% of the uranium was reccould be accounted for at thwas vaporized and dispersed Microscopic uranium was ducertain meteorological conduranium were propelled con1961). 

Consideration of dose assignburning operations should bpotential internal and externcleanup activities and incideBased on a limited amount odeveloped inhalation dose mdrivers that are based on 95t

be claimant favorable. SC&sampling data from Firing S1959, and ending December data with information presenTBD (Hickey et al. 2007). Tdoes not support use of the 9

outside air concentration of 

 has been redacted as of February 3, 2010. Note, however, that 

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claimant favorable. SC&A in this case, and finds it incointakes for unmonitored wornature of the fired materials 

11 Validation that the 

Most Highly Exposed 

Workers [Petitioner Issue]1

Overall, personal monitoring was focused on those workers most likely to be exposed to radiation—radiography technicians, production technicians, material handlers, transportation workers, quality control technicians/inspectors, and warehouse production workers. Other workers at Pantex had little occasion to enter radiological areas, and their potential for radiation exposure or intakes of radioactive materials were considerably less. 

The criteria or guidance that badged (and how well that p

were enforced) and for what beta, and neutrons); and how function of job type (includifacility, and time; needs to bwere appropriately badged treconstruction, and if that dacoworker database for unmoTBD does an analysis of the fifteen job categories, which assembly/production workerquality control/inspectors reThe petition and the externamonitoring by year indicatinwith the number of monitoreAssuming that workers who highly exposed does not valusing the distribution of cowworkers. Verification of moof changing badging practic

1 Issue correlates to the following petition concern: The assumption that available records reflect worst case scenarios or highe

does not appear to be borne out by worker histories. Draft Response to NIOSH ER Report – Rev. 1 15 

NOTICE: All information protected by Privacy Act 5 USC §552a has been redacted as of February 3, 2010. Note, however, that 

issues matrix will not be freely distributed to the public until further reviews for Privacy Act-protected information are 
PANTEX PLANT SEC ISSUES MATRIX – DRAFT PRELIMINARY SC&A ASSESSM

No. Issue SC&A’s Understanding of the NIOSH ER Position SC&A I

Draft Response to NIOSH ER Report – Rev. 1 16 

NOTICE: All information protected by Privacy Act 5 USC §552a

12 Accuracy of Available 

Radiation Exposure 

Data [Petitioner Issue]2

• The measured photon dose data, with appropriate corrections for 

lead apron use and dosimeter response uncertainty, provide reliable bounding photon doses. The available beta-dose data can also be used to calculate/establish bounding beta doses. 

• Neutron doses measured at Pantex with a new system since 

1994 are reliable, and these measurements are suitable for use in bounding the doses received by Pantex workers. Photon doses (with appropriate corrections for lead apron use and dosimeter response uncertainty) were reliably measured and can be used with a neutron-to-photon ratio to calculate conservatively bounding neutron doses for the years prior to 1994 (Fix et al. 2007) (ER, pg. 52). 

(1) The ER implies that ear

are reliable. The ER an

the inaccuracies in calibintroduced into the dosiimproper practices. In adosimetry program, the findings that concluded 

• Gamma calibra

TLDs ... did not 

• The scientist and 

assigned to the Pwere inadequate

• There were no f

for the Pantex d

• The quality of th

was less than ad

SC&A considers the deInvestigative Board to b

of dosimetry data for Pathese deficiencies for thof external dose reconst

(2) Further complicating m

not wearing their dosim

survey of film badge utifound several instances wearing their badges (Pthat involved inapproprunknown; however, radsubsequently establisheracks to determine whettheir badges. 

(3) Refer to Item #8 for a d

 has been redacted as of February 3, 2010. Note, however, that 

issues matrix will not be freely distributed to the public until further reviews for Privacy Act-protected information are 
PANTEX PLANT SEC ISSUES MATRIX – DRAFT PRELIMINARY SC&A ASSESSM

No. Issue SC&A’s Understanding of the NIOSH ER Position SC&A I

13 Too Few Workers 

Monitored for Valid 

Dose Reconstruction [Petitioner Issue]3

• The bounding doses for monitored workers can be used with 

coworker study statistics to assign bounding doses to unmonitored workers, because the monitored workers are considered the maximally exposed work group within the proposed class (based on historical Pantex radiological program documentation). The combination of these dose calculation methods make it feasible to bound the external dose (reconstruct the dose with sufficient accuracy) for the Pantex proposed 

worker class evaluated in this report (pg. 50) 

• NIOSH has obtained credible information stating that prior to 

1988, Pantex issued dosimeters only to workers likely to receive 10% or more of the radiation protection guidance. There is also 

strong evidence that a majority of the workforce was not exposed to radiological sources during that time period. From 1952 through 1957, the number of badged workers was particularly low, as industrial radiography and medical x-rays were the only significant sources of radiation exposure onsite during that time. Variations in the number of badged radiation workers from 1958 through 1988 reflect changes in weapons productions rates and the quantity of radioactive materials present onsite. Reviews conducted of the Pantex Plant health protection and monitoring programs have repeatedly found that monitoring levels are consistent with exposure potentials. Interviews with Pantex safety officers and health physicists working within the class timeframe also supported a proper correlation between exposure potentials and monitoring levels (pg. 51) 

(1) Statistics provided for e

based on limited data pr

(2) The ER does not provid

and non-radiological wothe number monitored. 

(3) Early monitoring was c

whereas later years incl

(4) The ER has not demons

radiation workers are thproduction rates and the material present. 

14 Records Incomplete for 

Subcontractor, 

Temporary, or ShortTerm Employees [Petition Issue]4

Response not specifically provided in the ER. SC&A response is pending a

Draft Response to NIOSH ER Report – Rev. 1 17 

NOTICE: All information protected by Privacy Act 5 USC §552a has been redacted as of February 3, 2010. Note, however, that 

issues matrix will not be freely distributed to the public until further reviews for Privacy Act-protected information are 
PANTEX PLANT SEC ISSUES MATRIX – DRAFT PRELIMINARY SC&A ASSESSM

No. Issue SC&A’s Understanding of the NIOSH ER Position SC&A I

Draft Response to NIOSH ER Report – Rev. 1 18 

NOTICE: All information protected by Privacy Act 5 USC §552a

15 Exposure from Tritium 

Leaks [Petition Issue]5

From available procedures, program reviews, and interviews conducted, it is evident that Pantex tritium monitoring has been appropriately focused on workers with the highest likelihood of exposure. As such, the data obtained can be used to bound tritium doses for all workers (pg. 39). 

(1) Reservoirs began arrivin

1957; however, there is 

prior to 1960 will be as

(2) The ER indicates that P

on workers with the higFurthermore, they indictritium dose. Prior to 1individuals were randombioassay from 1960–19the “highest likely expoand how they have veri

(3) Evaluation of Table 5-3 

indicates that the numbetritium uptakes was not monitored per year from pg. 15). In the absence NIOSH has proposed to from the 1970s for the y1972 to the present, unmassigned to production ttechnicians, and quality uses a triangular distriba mode and maximum athe missed dose (Hickey 

(4) The TBD does not clear

derive values in Table 5

used for determining thassumed without adequsupposed that tritium bimonitoring data were diUnmonitored tritium exjob classifications, whicindividuals handling res

 has been redacted as of February 3, 2010. Note, however, that 

issues matrix will not be freely distributed to the public until further reviews for Privacy Act-protected information are 
ft Response to NIOSH ER Report – Rev. 1 19 

NOTICE: All information protected by Privacy Act 5 USC §552a has been redacted as of February 3, 2010. Note, however, that 

issues matrix will not be freely distributed to the public until further reviews for Privacy Act-protected information are 

PANTEX PLANT SEC ISSUES MATRIX – DRAFT PRELIMINARY SC&A ASSESSM

No. Issue SC&A’s Understanding of the NIOSH ER Position SC&A I

components or those in these activities are perfoinclude those disposing tritium-contaminated eqreceiving or preparing ca few. 

16 Badge Placement 

[Petition Issue]6

Response not specifically provided in the ER. Worker geometry and proxim

pertinent to organ dose reco

workers required to work in those who held units in there its analysis of workplace radprovided an adequate basis fexposures during weapons cwere worn at the collar, as inThe highest exposures may resulting in an underestimate Dosimetry on the collar or ereflect the exposure to lower applied for glovebox workerbe appropriate for situations where radioactive material ithe body. The ER should evexceeding the measured who

17 Efficacy of the HP and 

IH Programs [Petitioner 

Issue/Raised in ER]7

Excerpts from a 1990 Tiger Team report at the Pantex Plant relayed information related to (and critical of) the following: health physics support staffing levels and training; questions regarding quality assurance for radiation monitoring data; health and safety program inadequacies; the control of radioactive sources; maintenance of employee exposure records; contamination reports; and discussion of pre-employment or new employee baseline monitoring. Although the report contains information which indicated that the Pantex Plant radiological program was deficient in implementing DOE Order 5480.11 requirements, the report did not find that 

(1) SC&A has addressed ad

records under Items #2 

exposure data, respectiv

(2) The characterization of 

conditions is addressed 

(3) Health physics support 

general health and safetcontrol of radioactive sobackground information 

Dra
ft Response to NIOSH ER Report – Rev. 1 20 

NOTICE: All information protected by Privacy Act 5 USC §552a has been redacted as of February 3, 2010. Note, however, that 

issues matrix will not be freely distributed to the public until further reviews for Privacy Act-protected information are 

PANTEX PLANT SEC ISSUES MATRIX – DRAFT PRELIMINARY SC&A ASSESSM

No. Issue SC&A’s Understanding of the NIOSH ER Position SC&A I

radiation exposures and radiation doses were not monitored, either through personal or area monitoring. With the exception of neutron monitoring, the Tiger Team review did not indicate that occupational exposure monitoring data obtained were deficient, inaccurate, or unsuitable for use in bounding doses to Pantex workers. 

source term, but are not reconstruction for an in

(4) Maintenance of survey 

and field air-sampling r

reconstruction effort in monitoring data, at leasreasonableness of the boinappropriately monitor

Dra
Addendum: Note regarding Burn Area Exposures 

Weapons components were in some cases recovered. To sanitize weapons components to render 

them unclassified, parts were removed and subjected to granulation, smelting, crushing, 

shredding, burning, incineration, and other processes. The average amount of hazardous material 

generated averaged about 75 pounds per weapon. This included DU as well as other metals and 

components (DOE 1995). In the early years, this material was handled with bare hands. In 

addition, burn pits were used to dispose of chemical wastes. The basis for determining exposure 

to uranium from burning activities was air-sampling activity for the period of 1960–1967. The 

default intake rate of DU for the burning ground was 130 pCi/day for 1952 to present. No airsampling data were available for 1952–1959 and 1963 (Hickey et al. 2007). 

Furthermore, dose assignment from hydroshot and burning operations should adequately reflect 

potential internal and external exposures, particularly from cleanup activities and incidental 

entries into these areas. Based on a limited amount of air-sampling data, NIOSH developed 

inhalation dose models for site operators and drivers that are based on 95th percentile values 

and appear claimant favorable. SC&A reviewed available air-sampling data at Firing Station 4 

starting October 27, 1959, and ending December 22, 1961, and compared these data with 

information presented in Figures 5-1 and 5-2 of the TBD (Hickey et al. 2007). The raw data 

SC&A reviewed does not support the determination that using the 95th percentile of 1960s 

outside air concentration of 24 pCi/m’ is appropriate or claimant favorable. SC&A questions the 

use of 1 DAC-hour in this case and finds it inconsistent with other calculated intakes for 

unmonitored workers, particularly considering the nature of the fired materials that were being 

remediated. The 19 pCi/d intake factor at Pantex is inconsistent with that used for IAAP.

Draft Response to NIOSH ER Report – Rev. 1 21 SC&A – March 27, 2009 

NOTICE: All information protected by Privacy Act 5 USC §552a has been redacted as of February 3, 2010. 

Note, however, that future versions of this issues matrix will not be freely distributed to the public until 

further reviews for Privacy Act-protected information are conducted. 
References 

DOE (U.S. Department of Energy) 1980. Report of the Investigation of a Radiation Exposure 

Incident at the Pantex Plant During September 1979, Albuquerque Operations Office, 

Albuquerque, New Mexico, January 10,1980. (Classified) 

DOE (U.S. Department of Energy) 1990. 1990 Tiger Team Assessment of the Pantex Plant, 

Amarillo, Texas, DOE/EH-0130, Department of Energy, Washington D.C., February 1, 1990. 

DOE (U.S. Department of Energy) 1995. Final Enivronmental Impact Statement for the 

Continued Operation of the Pantex Plant and Associated Storage of Nuclear Weapon 

Components, U.S. Department of Energy; DOE/EIS-0225; October 1995; 

http://www.globalsecurity.org/wmd/library/report/enviro/eis-0225/index.html. 

DOE (U.S. Department of Energy) 2001. [2000-2001 Investigation of the Rocky Flats Building 

771 Worker Exposure Report, Summary Report, 2001.] 

Drummond, J.C., 1961. Letter from J.C. Drummond (Pantex) to Goeckermann (LLNL). 

Fix, J.J., Martin, J.B., Strom, D.J., Traub, R.J., and Stansbury, P.S., 2007. Pantex Plant National 

Security Complex – Occupational External Dose, ORAUT-TKBS-0013-6, Revision 01, Oak 

Ridge Associated Universities Team, Oak Ridge, Tennessee, June 22, 2007. 

Helgeson, 1989. Report of In Vivo Counting for Mason & Hanger Silas Mason Co., Inc. Pantex 

Plant-Work Performed on September 22 through October 6, 1989, Helgeson Scientific Services, 

November 3, 1989, SRDB Ref ID: 14337. 

Hickey, E.E., Bihl, D.E., and Strom, D.J., 2007. Pantex Plant – Occupational Internal Dose, 

ORAUT-TKBS-0013-5, Revision 01, Oak Ridge Associated Universities Team, Oak Ridge, 

Tennessee, June 22, 2007. 

Jones, R. and D. Levell, 2004. Metal Tritides Technical Basis Document, RSD-TBD-0036, Issue 

A, BWXT Pantex Plant, Amarillo, Texas. March 1, 2004. 

National Bureau of Standards, 1955, Intercomparison of Film Badge Interpretations, from 

“Isotopics;” National Bureau of Standards; April 1955; SRDP Ref ID: 3640. 

NIOSH (National Institute for Occupational Safety and Health) 2008. NIOSH SEC Petition 

Evaluation Report Petition SEC-00068, Revision 0, August 5, 2008, Office of Compensation 

Analysis and Support, Cincinnati, Ohio. 

Personal Communication, October 1, 2003, Personal Communication with [Name Redacted], 

communication with a member of the Pantex Radiation Safety Department, October 1, 2003, 

SRDB Ref ID: 11077 

Draft Response to NIOSH ER Report – Rev. 1 22 SC&A – March 27, 2009 

NOTICE: All information protected by Privacy Act 5 USC §552a has been redacted as of February 3, 2010. 

Note, however, that future versions of this issues matrix will not be freely distributed to the public until 

further reviews for Privacy Act-protected information are conducted. 
Personal Communication, April 8, 2008, Personal Communication with [Name Redacted]; 

communication with site expert; April 8, 2008, SRDB Ref ID: 46110. 

Poynor, E.D., 1969. Memorandum from E.M. Poynor (Pantex Plant) to D.W. Hardwick, Survey 

of Utilization of Film Badges June 17, 1969 — June 23, 1969, Mason and Hanger-Silas Mason 

Co., Inc., Amarillo, Texas. July 7, 1969. 

Rawlston, J.E., 1991, Final HERS Phase III Status Report, memorandum to W.E. Ivie, Delphi 

Group; J.E. Rawlston (Pantex); September 12, 1991; SRDB Ref ID: 14258. 

Special Exposure Cohort Petition SEC-00068, Pantex Plant, All employees who worked in all 

facilities at the Pantex Plant in Amarillo, Texas, from January 1, 1951 through December 31, 

1991, Petition qualified by NIOSH on November 20, 2007. 

Strom, unknown date. Log Probability Analysis of Grouped Pantex Photon and Neutron 

Dosimeter Data; Dan Strom, Oak Ridge Associated Universities Team (ORAUT); SRDB Ref 

ID: 21850.

Draft Response to NIOSH ER Report – Rev. 1 23 SC&A – March 27, 2009 

NOTICE: All information protected by Privacy Act 5 USC §552a has been redacted as of February 3, 2010. 

Note, however, that future versions of this issues matrix will not be freely distributed to the public until 

further reviews for Privacy Act-protected information are conducted. 
ATTACHMENT 1: EXAMPLES OF NEUTRON-TO-PHOTON RATIO (n/p) VALUES 

GREATER THAN THE RECOMMENDED 1.7 VALUE AT PANTEX 

(a) 1960 and 1979 n/p Values for Some Inspectors and Warehouse Workers Exceeded 1.7 

See pages 41 and 42 of TKBS-0013-6 for details; Section 6.6.3 recommends using the higher 

n/p value measured instead of the n/p value of 1.7 for these cases. However, this measured 

n/p value would be derived from unreliable NTA film results because they are not sensitive 

to lower energy neutrons; hence this is not technically sound or favorable to claimant. 

(b) 1979 Measurements on Pits in Shipping Containers and in High Explosives (HE) 

Measurements by instruments in 1979 suggest that the n/p value for pits in shipping 

containers and pits in HE exceed the n/p value of 1.7 for some workers; in such areas as 

radiography, inspection, storage, and transportation of weapons. 

(DOE, Report of the Investigation of a Radiation Exposure Incident at the Pantex Plant 

During September 1979, January 10, 1980, as cited in pages 16 and 109 of SC&A's 

7/17/2008 review of Pantex Site Profile) 

(c) Data from Documents listed on Pages 65 and 66 of NIOSH's SEC ER of July 10, 2008 

SRDB 

Ref ID# 

Document 

pdf.page Date Area Neutron 

(mrem/hr) 

Gamma

(mR/hr) n/p 

14319 5 9/12/1975 12-42 North vault 11.159 5.5 2.03

25440 18 10/12/1983 12-2 Source Rm 1.8 0.6 3.00

25440 18 10/12/1983 12-2 Source Rm 2 0.5 4.00

25440 18 10/12/1983 12-2 Source Rm 3 0.4 7.50

25440 18 10/12/1983 12-2 Source Rm 0.4 0.1 4.00

14148 8 4/14/1983 12-2 Source Rm 3.9 0.95 4.11

14158 3 5/21/1986 12-42 Test Bay* 0.5 0.175 2.86

14158 3 5/21/1986 12-42 Test Bay* 0.6 0.188 3.19

25471 4 2/18/1987 12-10 Source Rm** 1.8 0.4 4.50

25471 4 2/18/1987 12-10 Source Rm** 1.8 0.6 3.00

25471 4 2/18/1987 12-10 Source Rm** 1.9 0.4 4.75

25471 4 2/18/1987 12-10 Source Rm** 7.8 1.0 7.80

25471 4 2/18/1987 12-10 Source Rm** 5.3 1.7 3.12

25471 4 2/18/1987 12-10 Source Rm** 7.1 1.0 7.10

25471 4 2/18/1987 12-10 Source Rm** 3.8 0.8 4.75

25471 4 2/18/1987 12-10 Source Rm** 27.1 2.0 13.55

25471 4 2/18/1987 12-10 Source Rm** 26.8 2.0 13.40

25471 4 2/18/1987 12-10 Source Rm** 28.3 3.0 9.43

Draft Response to NIOSH ER Report – Rev. 1 24 SC&A – March 27, 2009 

NOTICE: All information protected by Privacy Act 5 USC §552a has been redacted as of February 3, 2010. 

Note, however, that future versions of this issues matrix will not be freely distributed to the public until 

further reviews for Privacy Act-protected information are conducted. 
SRDB 

Ref ID# 

Document 

pdf.page Date Area Neutron 

(mrem/hr) 

Gamma

(mR/hr) n/p 

25471 4 2/18/1987 12-10 Source Rm** 38 7.2 5.28

25471 4 2/18/1987 12-10 Source Rm** 23.1 3.5 6.60

25508 5 8/9/1990 12-21 Neutron Radio. 2.0 0.3 6.67

25508 5 8/9/1990 12-21 Neutron Radio. 1.0 0.3 3.33

* non-radiation worker area where a value of n/p = 0.8 would be used in DR. Average = 5.6 

**With Cf-252 source extended. GM = 5.0

Range = 2.0-13.6

(d) 1992–1995 Radiation Surveys of Different Weapon Types

Weapons program Neutron-to-proton ratio greater than 1.7 

48 Yes, in certain configurations 

57 No 

61 Yes, in certain configurations 

62 No 

68 Yes, in certain configurations 

71 No 

76 No 

78 No 

79 Yes, approximately 10:1 ratio* 

80 Yes, in certain configurations 

83 No 

87 Yes, in certain configurations 

*Survey data was limited for this unit. 

Source: Pantex 1992, Pantex 1993, Pantex 1994, Pantex 1995a, Pantex 1995b. 

(From page 65 of SC&A's 7/17/2008 review of Pantex Site Profile. 

Surveys taken with Victoreen 440 and Rem Ball instruments.) 

Draft Response to NIOSH ER Report – Rev. 1 25 SC&A – March 27, 2009 

NOTICE: All information protected by Privacy Act 5 USC §552a has been redacted as of February 3, 2010. 

Note, however, that future versions of this issues matrix will not be freely distributed to the public until 

further reviews for Privacy Act-protected information are conducted. 
ATTACHMENT 2: SC&A’S RESPONSE TO NIOSH’S EVALUATION REPORT 

CONCERNING EXTERNAL DOSE FOR PANTEX SEC-00068 

NIOSH’s ER Position concerning External Dose for Pantex SEC-00068

Page 26 of the ER states the following: 

The TBD neutron-to-photon ratios are based on worker dosimeter measurements 

that were recorded using the Panasonic UD-809/UD-812 system and correspond 

to doses in which both the photon and neutron doses of the individual exceeded 

50 mrem per year. From these data, a median neutron-to-photon ratio of 0.8 

and a 95th percentile value of 1.7 were calculated. For dose reconstruction of 

monitored workers, NIOSH recommends the 95th percentile neutron-to-photon 

ratio of 1.7. [Emphasis added.] 

NIOSH claims that the neutron doses at the Pantex facility can be bound by this method. 

Page 47 states the following: 

Neutron doses measured at Pantex since this time [1993] with this new system are 

considered reliable for use in this radiological dose reconstruction program, and 

these measurements provide a basis for using neutron-to-photon dose ratios to 

permit estimating worker neutron doses for the periods prior to the accreditation. 

Based on NIOSH’s review and evaluation of the weapons systems handled at 

Pantex, and the assembly of the list that permits comparison across all times 

associated with this evaluation, NIOSH is able to establish that the neutron-tophoton dose ratios, applied to bounding photon doses, result in calculated 

neutron doses that are considered bounding across all time periods. The 

method used to bound neutron doses is addressed in Section 7.3.4. [Emphasis 

added.] 

Section 7.3.4, page 50, states the following: 

Photon doses (with appropriate corrections for lead apron use and dosimeter 

response uncertainty) were reliably measured from 1994 forward and can be 

used with a neutron-to-photon dose ratio of 1.7 to calculate neutron doses for the 

years prior to 1994 (ORAUT-TKBS-0013-6; Strom, unknown date). The average 

neutron-to-photon dose ratio determined from reliable collective neutron and 

photon doses measured since 1994 is only 0.25 (see Table 6.1 in ORAUT-TKBS0013-6). Thus, this method for calculating neutron doses prior to 1994 will result 

in average neutron doses to workers that are approximately 6.8 times the 

expected doses, which will be bounding (ORAUT-TKBS-0013-6) for the class 

evaluated in this report. [Emphasis added.] 

Note that there is apparently an error in the first sentence in the statement above, because it 

currently reads as though the photon doses measured from 1994 forward can be used along with 

Draft Response to NIOSH ER Report – Rev. 1 26 SC&A – March 27, 2009 

NOTICE: All information protected by Privacy Act 5 USC §552a has been redacted as of February 3, 2010. 

Note, however, that future versions of this issues matrix will not be freely distributed to the public until 

further reviews for Privacy Act-protected information are conducted. 
the n/p value of 1.7 to calculate neutron doses for years prior to 1994; what it most likely means 

is that the photon doses measured from 1994 forward can be used to determine the n/p values of 

0.8 and 1.7 so that the photon doses measured prior to 1994 can be used to calculated neutron 

doses prior to 1994. 

SC&A’s Response to NIOSH’s ER Position concerning External Dose at Pantex

While the recommended n/p method may bound some of the Pantex worker’s neutron dose, it 

cannot be assured that it will bound all workers’ neutron doses for 1951–1992 because of the 

following issues: 

(a) Back-extrapolating to previous 42 years not supported – The n/p value of 0.8 and 1.7 

was obtained from 43 data points taken during the period of 1993–2003 (no data for 

1997), the data is reasonably distributed during this period with 4 to 5 points per each 

year. However, there is no supporting evidence that the operating conditions and 

radiation fields were sufficiently similar during this period to the previous 42 year period, 

1951–1992. The only mention of this issue in NIOSH’s ER was on page 47 where it is 

stated, “Based on NIOSH’s review and evaluation of the weapons systems handled at 

Pantex, and the assembly of the list that permits comparison across all times associated 

with this evaluation...” There is no further supporting evidence or references provided. 

Bench-mark measurements would have to have been made to establish a relationship 

between the n/p values during the early period compared to the latter period when the n/p 

value was derived. NTA film results cannot be used for this purpose because they have 

been deemed unreliable. Documentation of dose measurements (such as by survey 

instruments) at various locations and time periods compared to the 1993-2003 neutron 

and photon dose measurements would be required to determine rather radiation fields 

were compatible or not to justify use of NIOSH’s recommended method and n/p values. 

(b) Examples where n/p of 1.7 is not bounding – There are numerous examples, over a 

significant time period (1960–1995) that indicates that using an n/p value of 1.7 would 

not bound the neutron dose. See Attachment 1 for some examples where the n/p values 

ranged from 2.0 to 13.6, with a GM = 5.0, when measured during surveys. Additionally, 

if a worker’s recorded NTA film results shows a dose greater than that calculated using 

an n/p value of 1.7, it cannot be used (as recommended in ORAUT-TKBS-0013-6, page 

42) because the correct neutron dose is not known from the NTA film results, which have 

been deemed unreliable. SC&A performed a preliminary review of 14 Pantex claims and 

found that where neutron doses were assigned, the dose reconstructions did not always 

use an n/p value of 0.8 for unmonitored and 1.7 for monitored workers, but instead used 

n/p values ranging from 0.25 to 2.5; only 50% of the time were the recommended n/p 

values of 0.8 or 1.7 used. SC&A found that n/p values of 0.25, 0.80, 1.0, 1.7, 2.0, and 2.5 

were used in the cases examined to date. 

(c) Comparison to collective dose n/p value not valid – The statement on page 50 of the 

ER that the recommended n/p value of 1.7 is 6.8 times the n/p value of 0.25 derived from 

collective doses is not a valid comparison because much of the collective photon dose 

Draft Response to NIOSH ER Report – Rev. 1 27 SC&A – March 27, 2009 

NOTICE: All information protected by Privacy Act 5 USC §552a has been redacted as of February 3, 2010. 

Note, however, that future versions of this issues matrix will not be freely distributed to the public until 

further reviews for Privacy Act-protected information are conducted. 
was from workers who had only photon doses; hence the results were diluted by photon 

doses. This was discussed by NIOSH in ORAUT-TKBS-0013-6, page 33, where it is 

stated that “However, these ratios are not directly applicable to claimants because they 

are derived from collective doses. They do not take into account the “diluting” effect of 

numerous workers who had photon doses only (Martin, 2006b).” The annotations in 

brackets are further discussed on page 56. Therefore, the ER statement concerning the 

factor of 6.8 times is somewhat misleading. 

(d) Reliability of recorded photon dose not established – While SC&A agrees that the 

systems used to create and store external dose records at Pantex appears to be adequate, it 

is not as apparent that the measured photon doses are as reliability as are required for use 

to assign both photon dose and to derived the neutron doses, while relying on only one 

measured parameter, the photon dose. An error in photon dose assignment is magnified 

by a factor of 2.7 (for example, if a 100 mrem photon reading is in error by 10%, this 

leads to: 10 mrem photon + 1.7 n/p × 10 mrem = 27 mrem total error; this is a total error 

of 27%). 

In the ER, NIOSH states the following on page 46: 

Since first used, the film badges and TLDs assigned at Pantex have been capable 

of measuring photon exposures in the workplace with sufficient accuracy to 

permit the calculation of bounding photon exposures. There is strong evidence 

that workers who had the highest potential for radiation exposure were monitored 

with state-of-the-art dosimeters (National Bureau of Standards, 1955) and the 

measured photon doses were reasonably accurate and complete (ORAUT-TKBS0013-6). Dosimetry records maintained by the Radiation Safety Department have 

been independently reviewed by the HERS project to verify accuracy and to 

ensure complete documentation (Rawlston, 1991). 

In TKBS-0013-6, page 28, NIOSH states, “Photon radiation in the workplace would have been 

readily measured at Pantex, with available dosimeter technology, during all years of operation.”

However, SC&A has identified the following areas of concern: 

• Calibration using medium to high energy photons (Co-60 and Cs-137), when major 

photon fields were 60 keV. 

• Early photon dosimetry under response as well as over response must be considered. 

• Wide range of photon energies present in work areas. 

• Three different dosimetry vendors used without access to classified photon energy 

spectra. 

• Pantex TBD and SEC ER states photon dosimetry was correct, while IAAP TBD, for 

similar operations, state that only 37% of 60 keV dose was measured. 

Draft Response to NIOSH ER Report – Rev. 1 28 SC&A – March 27, 2009 

NOTICE: All information protected by Privacy Act 5 USC §552a has been redacted as of February 3, 2010. 

Note, however, that future versions of this issues matrix will not be freely distributed to the public until 

further reviews for Privacy Act-protected information are conducted. 
• DOE Investigative Board findings are relevant to the credibility of photon; and hence, 

neutron dose reconstruction at Pantex. 

The support for these concerns includes the following: 

Calibration vs. Work Area Photon Energies

Dosimeters were calibrated using medium to high energy photons (Co-60 and Cs-137, page 23 of 

ORAUT-TKBS-0013-6), but according to pages 25 and 54 of ORAUT-TKBS-0013-6, the 

predominant source of radiation dose at Pantex is photons from Am-241, with the 60 keV photon 

being the most significant energy. This would lead to the film over responding in the open 

window (OW) of the badge (shallow dose), but could lead to the film under-responding under 

the shielded portion of the badge (deep dose) for some earlier dosimeters with thick filters, such 

as 1 mm Pb. This is discussed in detail in SC&A’s evaluation of the Pantex Site Profile on pages 

51–56 [SCA 2008] 

Additionally, there was a wide range of photon energies present in the various work areas at 

Pantex as stated on page 24 of ORAUT-TKBS-0013-6. This would require different calibration 

factors for different work areas if the dosimeters were calibrated using only one photon energy 

spectrum. 

Three different dosimetry vendors performed the dosimetry services for Pantex, yet the details of 

the photon energy fields were not available to them for use in calibration because this 

information was classified. This would not provide for a situation where the dosimeter results 

could be demonstrated to be technically reliable by matching the calibration photon energy 

spectra to the work place photon energy spectra. 

As illustrated above, NIOSH’s SEC ER and the Pantex TBD states that photon dosimetry results 

were correct without any correction factors, except for lead aprons; while IAAP, a facility with 

similar operations, TKBS-0018 [ORAUT 2005] states that only 37% of 60keV photon dose was 

measured and recommends a correction factor of 1/0.30 = 3.33 based on Hanford studies. 

Comparing the TBDs for IAAP and Pantex leads to the conclusion that the two plants were very 

similar in operations and functions; however, the recommendations for low-energy photon dose 

corrections are inconsistent with each other; one using a correction factor of 3 and the other a 

correction factor of 1.0. 

Problems Identified during Investigation are Relevant 

DOE Investigative Board finding are relevant to the credibility of photon; and hence, neutron 

dose reconstruction at Pantex. As late as 1979, when TLD dosimeters were being used, the 

procedures for, and characteristics of, photon exposures at the Pantex plant were not completely 

documented or understood. The dosimetry section at that time appears to have been under 

staffed and not sufficiently equipped to support NIOSH’s statement that the photon dose of 

record are accurate and do not require any adjustment factors. Some of the deficiencies are 

discussed in SC&A’s review of the Pantex TBD (SC&A 2008) and provided in detail in a 

classified report issued in 1980 by DOE, titled, Report of the Investigation of a Radiation 

Draft Response to NIOSH ER Report – Rev. 1 29 SC&A – March 27, 2009 

NOTICE: All information protected by Privacy Act 5 USC §552a has been redacted as of February 3, 2010. 

Note, however, that future versions of this issues matrix will not be freely distributed to the public until 

further reviews for Privacy Act-protected information are conducted. 
Exposure Incident at the Pantex Plant During September 1979 (DOE 1980). These deficiencies 

in the dosimetry program as late as 1979 raises ever more concerns about the reliability of prior 

photon dose of record; especially in the early years when dosimetry was less advanced.

References: 

ORAUT (Oak Ridge Associated Universities Team) 2005. Technical Basis Document for 

Atomic Energy Operations at the Iowa Ammunition Plant (IAAP), ORAUT-TKBS-0018, 

Revision 01, Oak Ridge Associated Universities Team, Cincinnati, Ohio. March 14, 2005. 

ORAUT (Oak Ridge Associated Universities Team) 2007. Pantex Plant – Occupational 

External Exposure, ORAUT-TKBS-0013-6, Revision 0, Oak Ridge Associated Universities 

Team, Cincinnati, Ohio. June 22, 2007.

SC&A 2008. Pantex Plant Site Profile Review, Revision 1-Draft. S. Cohen and Associates, 

Vienna, Virginia. July, 17, 2008.

Draft Response to NIOSH ER Report – Rev. 1 30 SC&A – March 27, 2009 

NOTICE: All information protected by Privacy Act 5 USC §552a has been redacted as of February 3, 2010. 

Note, however, that future versions of this issues matrix will not be freely distributed to the public until 

further reviews for Privacy Act-protected information are conducted.