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In response to Technical Task Request (TTR) HLW-SSF-TTR-2012-0017 (1), SRNL performed modeling studies to evaluate alternative design features for the 32 million gallon Saltstone Disposal Unit (SDU) referred to as SDU 6. This initial modeling study was intended to assess the performance of major components of the structure that are most significant to the PA. Information provided by the modeling will support the development of a SDU 6 Preliminary Design Model and Recommendation Report to be written by SRR Closure and Waste Disposal Authority. Key inputs and assumptions for the modeling were provided to SRNL in SRR-SPT-2011-00113 (2). A table reiterates the base case and four sensitivity case studies requested in this reference. In general, as shown in Table 4, when compared to Vault 2 Case A, the Base Case SDU 6 design produced higher peak fluxes to the water table during the 10,000 year period of analysis but lower peak fluxes within a 15,000 to 20,000 time frame. SDU 6 will contain approximately ten times the inventory of a single Vault 2 and the SDU 6 footprint is comparable to that of a group of four Vault 2 disposal units. Therefore, the radionuclide flux from SDU 6 and thatmore » from a single Vault 2 are not directly comparable. A more direct comparison would be to compare the maximum dose obtained at the 100 m boundary from the seven SDU's that will replace the 64 FDC's analyzed in the 2009 PA. This analysis will be performed in the next set of calculations planned for SDU design evaluation. Aquifer transport and dose calculations were not intended to be part of this initial scoping study. However, results from this study do indicate that replacement of the FDC design with SDU would not yield significantly higher peak doses. If the thickness of the SDU 6 floor is increased, peak doses would not occur during the 10,000 year period of analysis.« less

High level waste at the SRS F- and H-Area Tank Farms consists of both sludge and supernate fractions. Supernate contains soluble species. Sludge contains both insoluble species and entrained supernate. The nature and extent of contamination present on waste generated during operation of the F- and H-Area Tank Farms is a function of the tank, the nature of the job generating the waste, variability in waste handling techniques, and other factors. Historically, supernate-contaminated waste had been segregated and manifested as supernate waste. A single, comprehensive characterization for supernate has been developed previously (Reference 4). Sludge-contaminated waste has been manifested by combining sludge and supernate waste streams to account for entrained supernate present in sludge. Separate sludge waste stream characterizations have been developed for each of the F- and H-Area Tank Farms (Ref. 1 and 2). Low-activity waste (LAW) consists of both sludge and supernate fractions. Routine LAW is waste that has a maximum dose rate of 50mrem/hr at 5cm for Sealands and 35mrem/hr at 5 cm for Roll-Offs. However, it is intended that routine, low-activity waste not be segregated; therefore, individual low-activity waste cuts may consist of items contaminated with either supernate or sludge in the same container. Historical waste generation rates of the two waste streams will be used to develop a single waste stream distribution representative of low-activity waste. The single distribution is based on the assumption that the actual contamination present on waste in a series of containers from these tanks will be representative of the average supernate/sludge radionuclide distribution. This document develops a characterization for low-activity waste consisting of both radioactive and hazardous constituents. The characterization includes quantification of the average Sealand and Roll-Off containers of routine, low-activity waste. This characterization will apply only to low-level waste that has a whole body (30 cm) dose rate less than or equal to 5 mrem/hr from an individual waste bag or item and has a radionuclide distribution that is represented by the existing high level supernate and sludge waste streams (FHW-00001 and HTK-00002). This document specifically refers to the issues of waste management related to the F- and H-Area Tank Farms. However, the characterization presented in this document of low-activity waste managed in Sealand and Roll-Off containers applies to any SRS facilities that process the supernate or sludge waste streams that are presently stored in the F- and H-Area Tank Farms.

A set of calculations performed with the MARS15 code indicates a maximum radiation dose due to muons in the C0 Assembly Building (C0 AB) for a person standing on a ladder in the orbit plane of the Tevatron of 10 mrem and a maximum dose for a person standing on a C0 AB floor < 1 mrem per loss of 2.5 x 10{sup 13} protons of 1 TeV energy in the Tevatron.

The operation of the NuMI beamline will result in the production of significant quantities of airborne radionuclides due to the large proton beam intensities to be delivered to this facility. In this report we predict the production of airborne radionuclides and their release to the environment during NuMI operations. An estimate is provided of the maximum dose equivalent that might be delivered by this pathway to a hypothetical individual continuously present at the Fermilab site boundary. Likewise, the dose equivalent rate due to exposure to activated air within the NuMI target station enclosure is estimated. It is concluded that the airborne radioactivity produced in the course of NuMI operations will be in compliance with applicable Federal and State regulations.

The INEL Radiological Control Performance Indicator Report is provided quarterly, in accordance with Article 133 of the INEL Radiological Control Manual. Indicators are used as a measure of performance of the Radiological Control Program and as a motivation for improvement, not as a goal in themselves. These indicators should be used by management to assist in focusing priorities and attention and adherence to As-Low-As-Reasonably-Achievable (ALARA) practices. The INEL Radiological Control Performance Indicators consist of: collective dose in person-rem; average worker dose, maximum dose to a worker, and maximum neutron dose equivalent to a worker; number of skin and clothing contaminations, including the number of contaminated wounds and facial contaminations; number of radioactive material intakes resulting in a dose assessment of 10 mrem or more; area of contamination, high contamination, and airborne radioactivity areas, in square feet; and airborne radioactivity events and spills.

The INEL Radiological Control Performance Indicator Report is provided quarterly, in accordance with Article 133 of the INEL Radiological Control Manual. Indicators are used as a measure of performance of the Radiological Control program and as a motivation for improvement, not as a goal in themselves. These indicators should be used by management to assist in focusing priorities and attention and adherence to As-Low-As-Reasonably-Achievable (ALARA) practices. The INEL Radiological Control Performance Indicators consist of: collective dose in person-rem; average worker dose, maximum dose to a worker, and maximum neutron dose equivalent to a worker; number of skin and clothing contaminations, including the number of contaminated wounds and facial contaminations; number of radioactive material intakes resulting in a dose assessment of 10 mrem or more; area of contamination, high contamination, and airborne radioactivity areas, in square feet; and airborne radioactivity events and spills.

The INEL Radiological Control Performance Indicator Report is provided quarterly, in accordance with Article 133 of the INEL Radiological Control Manual. Indicators are used as a measure of performance of the Radiological Control Program and as a motivation for improvement, not as a goal in themselves. These indicators should be used by management to assist in focusing priorities and attention and adherence to As-Low-As-Reasonably-Achievable (ALARA) practices. The INEL Radiological Control Performance Indicators consist of: collective dose in person-rem; average work dose, maximum dose to a worker, and maximum neutron dose to a worker; the number of skin and clothing contaminations, including the number of contaminated wounds and facial contaminations; the number of radioactive material intakes resulting in a dose assessment of 10 mrem or more; the area of contamination, high contamination, and airborne radioactivity areas in square feet; and airborne radioactivity events and spills.

This report provides summary results of the Calendar Year (CY) 1994 As Low As Reasonably Achievable (ALARA) Program performance at the Pacific Northwest Laboratory (PNL). This report includes data regarding performance in the area of personnel exposures to radiation, skin contaminations, control of contaminated areas, minimization of radioactive waste, and control of radioactive releases. In CY 1994: (1) The collective total effective dose equivalent to PNL employees during 1994 was 55 person-rem. The Field Dosimetry Services of the Radiological Control Department, Technical Support Section, projected that no PNL employee`s dose would exceed 2 rem based on dosimeters processed during the year; no worker actually exceeded the projection-by the end of CY 1994. The maximum dose to any individual was 1.11 rem. (2) There were 34 instances of skin and personal-clothing contamination events for PNL employees during 1994. Eighteen of these contamination events occurred at the 324 Building; eleven occurred at the 325 Building; two occurred in the 327 Building; one occurred in the 326 Building; one occurred in the 3708 Building; and one occurred in the RTL Building. (3) PNL facilities contained 12 Airborne Radioactivity Areas, and 60 Contamination Areas and High Contamination Areas. The area of the Airborne Radioactivity Areas was 383 m{sup 2}(4125 ft{sup 2}). The area of the Contamination Areas was 5290 m{sup 2}(56,947 ft{sup 2}). The area of the High Contamination Areas was 266 m{sup 2}(2863 ft{sup 2}). (4) PNL disposed of 10.5 m{sup 3}(371 ft{sup 3}) of compacted low level waste. Also disposed was 423 m{sup 3} (14,949 ft{sup 3}) of noncompacted low level and mixed waste that was not subject to volume reduction. The total radioactivity of the disposed waste was 1217 Ci. (5) PNL facilities released 165.2 Ci of noble gas, 3.0E-5 Ci of airborne particulate radioactive material, and 12.2 Ci of tritium to the environment.

An offsite individual residing at the SRS boundary at the point of the maximum exposure (maximum individual) received a dose of 0.11 mrem from SRS atmospheric releases in 1993 (See Table 1 for a 5-yr history of doses). This dose was only 1.1% of the EPA public dose limit of 10 mrem/yr (DOE, 1990). Tritium oxide releases were responsible for 90% of the atmospheric dose. Ninety-nine percent of the atmospheric dose was accounted for with the inclusion of I-129, U-235, U-238, Pu-238 and Pu-239. The 50-mile population received a collective dose of 7.6 person-rem from 1993 atmospheric releases. Ninety-nine percent of this dose also resulted from the release of the same isotopes that dominated the maximum individual dose due to atmospheric releases. For both the individual and the population, atmospheric radiation dose was dominated by the inhalation and vegetation consumption pathways. The maximum dose received by an offsite individual as a result of SRS liquid releases in 1993 was 0.14 mrem (See Table 1 for a 5-yr history). This does was only 3.5% of the EPA limit for drinking water of 4 mrem/yr (DOE, 1990). This dose was dominated by Cs-137 accumulated in Savannah River fish and tritium in drinking water. More than 99% of the maximum individual dose from liquid releases resulted from tritium, Sr-90, Cs-137,and Pu-239. The population dose from liquid releases in 1993 was 1.5 person-rem. Again, tritium, Sr-90, Cs-137, and Pu-239 contributed more than 99% of this dose. The major exposure pathway to the population was drinking water. Radiation dose to the general public from operations at the Savannah River Site continued to be a very small fraction of the natural background dose. A resident of the CSRA receives about 300 mrem per year from background radiation. The population within 80 km of the SRS (620,000) and at the downstream water treatment facilities (65,000), therefore, received a natural background population dose of approximately 200,000 person-rem during 1993.

The offsite individual residing at the SRS boundary location of maximum exposure (maximum individual) received a dose from SRS atmospheric releases in 1992 of 0.10 mrem. Tritium oxide releases were responsible for more than 90% of the atmospheric dose. Ninety-nine percent of the atmospheric dose is accounted for with the inclusion of I-129, U-235, Pu-238 and Pu-239. The 50-mile population received a collective dose of 6.4 person-rem from 1992 releases. Atmospheric radiation dose is dominated by the inhalation and vegetation consumption pathways. The maximum dose received by an offsite individual as a result of SRS liquid releases in 1992 was 0.13 mrem. This dose is dominated by Cs-137 that is accumulated in Savannah River fish and tritium in drinking water. More than 99% of the maximum individual dose from liquid releases results from Cs-137, tritium, Sr-90, and Pu-239. The population dose from liquid releases in 1992 was 2.5 person-rem. The major exposure pathway to the population is drinking water. Radiation dose to the general public from operations at the Savannah River Site continues to be a very small fraction of the natural background dose. A resident of the CSRA receives about 300 mrem per year from background radiation. The populationmore » within 50-miles of the SRS (620,000) and at the downstream water treatment facilities (65,000), therefore, receives a natural background population dose of approximately 200,000 person-rem.« less

Population radiation dose commitments have been estimated from reported radionuclide releases from commercial power reactors operating during 1988. Fifty-year commitments for a one-year exposure from both liquid and atmospheric releases were calculated for four population groups (infant, child, teen-ager and adult) residing between 2 and 80 km from each of 71 reactor sites. This report tabulates the results of these calculations, showing the dose commitments for both water and airborne pathways for each age group and organ. Also included for each of the sites is a histogram showing the fraction of the total population within 2 to 80 km around each site receiving various average dose commitments from the airborne pathways. The total collective dose commitments (from both liquid and airborne pathways) for each site ranged from a high of 16 person-rem to a low of 0.0011 person-rem for the sites with plants operating throughout the year with an arithmetic mean of 1.1 person-rem. The total population dose for all sites was estimated at 75 person-rem for the 150 million people considered at risk. The site average individual dose commitment from all pathways ranged from a low of 3 {times} 10{sup {minus}7} mrem to a high of 0.02 mrem. Nomore » attempt was made in this study to determine the maximum dose commitment received by any one individual from the radionuclides released at any of the sites. However, licensee calculation of doses to the maximally exposed individual at some sites indicated values of up to approximately 100 times average individual doses (on the order of a few millirem per year).« less

Potential maximum radiation doses rates were calculated for the Palmerton ore storage site in Palmerton, Pennsylvania. The RESRAD computer code, which implements the methodology described in the US Department of Energy's manual for establishing residual radioactive material guidelines, was used in this evaluation. Four potential scenarios were considered for the Palmerton ore storage site. Two scenarios were developed on the basis of industrial use of the site, and two were developed on the basis of residential use of the site. The scenarios also vary with regard to time spent at the site, sources of food consumed, and source terms. The RESRAD code was used to analyze potential radiation doses from three exposure pathways. The results indicate that the basic dose limit of 100 mrem/yr would not be exceeded in Scenarios A (industrial use, hot spot), B (industrial use, homogenous contamination), and C (residential use, homogenous contamination), but would be exceeded in Scenario D (residential use, hot spot). The potential maximum dose rates for Scenarios A, B, C, and D are 1.0 mrem/yr, 0.66 mrem/yr, and 360 mrem/yr, respectively. 3 refs., 3 tabs.

Population radiation dose commitments have been estimated from reported radionuclide releases from commercial power reactors operating during 1987. Fifty-year dose commitments for a one-year exposure from both liquid and atmospheric releases were calculated for four population groups (infant, child, teen-ager and adult) residing between 2 and 80 km from each of 70 reactor sites. This report tabulates the results of these calculations, showing the dose commitments for both water and airborne pathways for each age group and organ. Also included for reach of the sites is a histogram showing the fraction of the total population within 2 to 80 km around each site receiving various average dose commitments from the airborne pathways. The site average individual dose commitment from all pathways ranged from a low of 2 {times} 10{sup {minus}6} mrem to a high of 0.009 mrem. No attempt was made in this study to determine the maximum dose commitment received by any one individual from the radionuclides released at any of the sites. However, licensee calculation of doses to the maximally exposed individual at some sites indicated values of up to approximately 100 times average individual doses (on the order of a few millirem per year). 2 refs., 2more » figs., 7 tabs.« less

Potential limits for the shallow earth burial of transuranic elements were examined by simplified models of the individual pathways to man. Pathways examined included transport to surface steams, transport to ground water, intrusion, and people living on the burial ground area after the wastes have surfaced. Limits are derived for each pathway and operational limits are suggested based upon a dose to the organ receiving the maximum dose rate of 0.5 rem/y after 70 years of exposure for the maximum exposed individual.

Population radiation dose commitments have been estimated from reported radionuclide releases from commercial power reactors operating during 1978. Fifty-year dose commitments from a one-year exposure were calculated from both liquid and atmospheric releases for four population groups (infant, child, teen-ager and adult) residing between 2 and 80 km from each site. This report tabulates the results of these calculations, showing the dose commitments for both liquid and airborne pathways for each age group and organ. Also included for each site is a histogram showing the fraction of the total population within 2 to 80 km around each site receiving various average dose commitments from the airborne pathways. The total dose commitment from both liquid and airborne pathways ranged from a high of 200 person-rem to a low of 0.0004 person-rem with an arithmetic mean of 14 person-rem. The total population dose for allsites was estimated at 660 person-rem for the 93 million people considered at risk. The average individual dose commitment from all pathways on a site basis ranged from a low of 3 x 10/sup -6/ mrem to a high of 0.08 mrem. No attempt was made in this study to determine the maximum dose commitment received by anymore » one individual from the radionuclides released at any of the sites.« less

An unplanned release of tritium fron the Savannah River Plant occurred on July 31, 1987 from 9:17 to 9:55 a.m. EDT. The total release of elemental tritium and tritium oxide was 172,000 Ci. The initial estimate of the ratio of tritium oxide to total tritium was 11% (19,000 Ci), and the corresponding maximum dose to a person at the plant boundary was estimated to be 0.2 mrem. Later data indicated that the percent tritium oxide was 2.7% (4700 Ci) and the estimated maximum dose at the plant boundary was revised downward to 0.02 mrem. The population dose was estimated to be 0.22 person-rem. 4 refs., 15 figs., 9 tabs.

The analysis of a sediment core from the Enterprise reservoir in southwestern Utah has provided a record of fallout in the area dating to 1945. Assming that all the /sup 137/Cs fallout that occurred at Enterprise reservoir between 1951 and 1957 came exclusively from the Nevada tests, an upper limit of the integrated deposit from this source is 18 mCi/km/sup 2/ of /sup 137/Cs decay corrected to 1979 out of a total of 101 measured in 1979. The maximum infinity dose from the external radiation caused by this Nevada Test Site fallout is estimated to be 1700 mrad. This maximum dose is only a factor of two higher than the cumulative estimated dose in Enterprise derived from the radiological surveys conducted after each test. This indicates that the region around Enterprise reservoir did not experience an intrusion of fallout from NTS greatly in excess of what had been deduced from the post-shot external radiation surveys.

Population radiation dose commitments have been estimated from reported radionuclide releases from commercial power reactors operating during 1977. Fifty-year dose commitments from a one-year exposure were calculated from both liquid and atmospheric releases for four population groups (infant, child, teen-ager and adult) residing between 2 and 80 km from each site. This report tabulates the results of these calculations, showing the dose commitments for both liquid and airborne pathways for each age group and organ, Also included for each site is a histogram showing the fraction of the total population within 2 to 80 km around each site receiving various average dose commitments from the airborne pathways. The total dose commitment from both liquid and airborne pathways ranged from a high of 220 person-rem to a low of 0.003 person-rem with an arithmetic mean of 16 person-rem. The total population dose for all sites was estimated at 700 person-rem for the 92 million people considered at risk. The average individual dose commitment from all pathways on a site basis ranged from a low of 2 x 10{sup -5} mrem to a high of 0.1 mrem. No attempt was made in this study to determine the maximum dose commitment received bymore » any one individual from the radionuclides released at any of the sites.« less

Population radiation dose commitments have been estimated from reported radionuclide releases from commercial power reactors operating during 1982. Fifty-year dose commitments from a one-year exposure were calculated from both liquid and atmospheric releases for four population groups (infant, child, teen-ager and adult) residing between 2 and 80 km from each of 51 sites. This report tabulates the results of these calculations, showing the dose commitments for both liquid and airborne pathways for each age group and organ. Also included for each site is a histogram showing the fraction of the total population within 2 to 80 km around each site receiving various average dose commitments from the airborne pathways. The total dose commitments from both liquid and airborne pathways ranged from a high of 30 person-rem to a low of 0.007 person-rem for the sites with plants operating throughout the year with an arithmetic mean of 3 person-rem. The total population dose for all sites was estimated at 130 person-rem for the 100 million people considered at risk. The average individual dose commitment from all pathways on a site basis ranged from a low of 6 x 10/sup -7/ mrem to a high of 0.06 mrem. No attempt was mademore » in this study to determine the maximum dose commitment received by any one individual from the radionuclides released at any of the sites.« less

Expected environments for a defense high-level waste (DHLW) repository in salt have been predicted analogously to previous analyses for spent fuel (SF) and reprocessed commercial high-level wastes (CHLW). Environments predicted include near-field and far-field temperatures, fluid, pressure, and nuclear radiation fields. Some sensitivity studies have also been performed. The main results of the calculations reported here include the following: (1) rock temperatures, canister wall temperatures, and waste temperatures do not exceed 86, 94, and 101/sup 0/C, respectively; (2) the maximum brine inflow rate to an emplacement hole is 0.015 L/yr, occurring in the first 30 yr after emplacement. The total accumulation of brine migrating to the emplacement hole after 1000 yr is < 0.5 L; (3) gas pressures encountered by the waste package do not exceed 0.36 MPa prior to mine closure. After this time, it is conceivable that stress on the canister could approach the lithostatic rock stresses; (4) maximum dose rates in the salt are < 1400 rads/h.

Population radiation dose commitments have been estimated from reported radionuclide releases from commercial power reactors operating during 1979. Fifty-year dose commitments from a one-year exposure were calculated from both liquid and atmospheric releases for four population groups (infant, child, teen-ager and adult) residing between 2 and 80 km from each site. This report tabulates the results of these calculations, showing the dose commitments for both liquid and airborne pathways for each age group and organ. Also included for each site is a histogram showing the fraction of the total population within 2 to 80 km around each site receiving various average dose commitments from the airborne pathways. The total dose commitment from both liquid and airborne pathways ranged from a high of 1300 person-rem to a low of 0.0002 person-rem with an arithmetic mean of 38 person-rem. The total population dose for all sites was estimated at 1800 person-rem for the 94 million people considered at risk. The average individual dose commitment from all pathways on a site basis ranged from a low of 2 x 10/sup -6/ mrem to a high of 0.7 mrem. No attempt was made in this study to determine the maximum dose commitment received by any one individual from the radionuclides released at any of the sites.

Population radiation dose commitments have been estimated from reported radionuclide releases from commercial power reactors operating during 1986. Fifty-year dose commitments for a one-year exposure from both liquid and atmospheric releases were calculated for four population groups (infant, child, teen-ager and adult) residing between 2 and 80 km from each of 66 reactor sites. This report tabulates the results of these calculations, showing the dose commitments for both water and airborne pathways for each age group and organ. Also included for each of the sites is a histogram showing the fraction of the total population within 2 to 80 km around each site receiving various average dose commitments from the airborne pathways. The total dose commitments (from both liquid and airborne pathways) for each site ranged from a high of 31 person-rem to a low of 0.0007 person-rem for the sites with plants operating throughout the year with an arithmetic mean of 1.7 person-rem. The total population dose for all sites was estimated at 110 person-rem for the 140 million people considered at risk. The site average individual dose commitment from all pathways ranged from a low of 2 {times} 10{sup -6} mrem to a high of 0.02 mrem. Nomore » attempt was made in this study to determine the maximum dose commitment received by any one individual from the radionuclides released at any of the sites. 12 refs.« less

Population radiation dose commitments have been estimated from reported radionuclide releases from commercial power reactors operating during 1984. Fifty-year dose commitments from a one-year exposure were calculated from both liquid and atmospheric releases for four population groups (infant, child, teen-ager and adult) residing between 2 and 80 km from each of 56 sites. This report tabulates the results of these calculations, showing the dose commitments for both liquid and airborne pathways for each age group and organ. Also included for each of the sites is a histogram showing the fraction of the total population within 2 to 80 km around each site receiving various average dose commitments from the airborne pathways. The total dose commitments (from both liquid and airborne pathways) for each site ranged from a high of 110 person-rem to a low of 0.002 person-rem for the sites with plants operating throughout the year with an arithmetic mean of 5 person-rem. The total population dose for all sites was estimated at 280 person-rem for the 100 million people considered at risk. The site average individual dose commitment from all pathways ranged from a low of 6 x 10/sup -6/ mrem to a high of 0.04 mrem. No attemptmore » was made in this study to determine the maximum dose commitment received by any one individual from the radionuclides released at any of the sites.« less

A method is described for estimating the maximum internal dose that could result from the radionuclides released to an aquatic environment. By means of this analysis one can identify the nuclides that could contribute most to the internal dose, and determine the contribution of each nuclide to the total dose. The calculations required to estimate the maximum dose to an infant's bone subsequent to the construction of a sea-level canal are presented to illustrate the overall method. The results are shown to serve the basic aims of preshot rad-safe analysis and of guidance for postshot documentation. The usefulness of the analysis in providing guidance for device design is further pointed out. (author)