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PUBLIC HEALTH ASSESSMENT

IDAHO NATIONAL ENGINEERING AND ENVIRONMENTAL LABORATORY (U.S. DEPARTMENT OF ENERGY)
[a/k/a IDAHO NATIONAL ENGINEERING LABORATORY (USDOE)]
IDAHO FALLS, BUTTE, CLARK, JEFFERSON AND BIN COUNTIES, IDAHO


APPENDIX A. TABLES

Table A-1. Maximum Concentration of Non-Radiological Contaminants in On-Site Groundwater Monitoring Wells
Contaminant On-Site Monitoring Wells Comparison Value (ppb)
Maximum Conc. (ppb) Location Date Detection Frequency/ Total Sample
VOCs
1,4-dichlorobenzene 22 Unspecified 02/14/91 13/665 0.4 (RBC)
1,1-dichloroethene 19 Unspecified 11/21/96 52/1050 0.06 (CREG)
1,2-dichloroethane 6 Unspecified 10/11/94 6/702 0.4 (CREG)
1,2-dichloroethene (total) 9,900 Unspecified 11/21/95 83/382 55 (RBC)
1,2-dichloroethylene (cis) 7,700 Unspecified 04/26/94 205/651 70 (MCL)
1,2-dichloroethylene (trans) 3,900 Unspecified 04/26/94 146/420 200 (RMEG)
2,4-dinitrophenol 90 Unspecified 02/14/91 1/46 20 (RMEG)
1,1,1-trichloroethane 6,800 RWMC 08/12/97 13/22 200 (MCL)
1,1,2-trichloroethane 5 Unspecified 07/01/93 15/1060 0.6 (CREG)
1,1,2,2-tetrachloroethane 4 Unspecified 10/03/95 7/713 0.2 (CREG)
1,2,3-trichloropropane 46 Unspecified 08/10/93 4/541 0.002 (RBC)
Acetonitrile 440 Unspecified 07/20/98 11/263 120 (RBC)
Benzene 13 Unspecified 06/04/96 33/1,027 2 (CREG)
Bromodichloromethane 8 Unspecified 11/16/94 5/1033 0.6 (CREG)
Carbon Tetrachloride 8,900 RWMC perched NA 167/1,058 0.3 (CREG)
Chlorodibromomethane 2 Unspecified 02/15/95 3/697 0.4 (CREG)
Chloroform 1,200 D06-DL02 04/29/97 186/1,060 6 (CREG)
Chloromethane 490 Unspecified 11/14/94 19/697 2.1 (RBC)
Methylene Chloride 750 Unspecified 09/08/97 323/1,062 5 (CREG)
Trichloroethylene 32,000 TAN 06/16/93 585/1,068 5 (MCL)
Tetrachloroethylene 110 TAN 04/26/94 413/1063 5 (MCL)
Toluene 730 TAN 07/07/97 331/1,053 700 (IEMEG)
Vinyl Chloride 14 Unspecified 11/21/95 8/702 0.02 (CREG)
SVOCs, PCBs, and Pesticides
Di(2-Ethylhexyl)phthalate 370 Unspecified 05/16/95 59/179 3 (CREG)
Aroclor 1254 3.6 Unspecified 10/11/94 1/38 0.7 (CEMEG)
Metals
Antimony 867 TRA 02/12/91   6 (MCL)
Arsenic 1,080 TRA 02/12/91 504/1,319 0.02
Barium 25,300 Unspecified Perched 12/01/98 1,116/1,131 700 (RMEG)
Boron 3,930 Unspecified 07/01/93 5/5 100 (IEMEG)
Cadmium 2,360 RWMC Perched 12/01/98 269/1,454 5 (MCL)
Chromium (Total) 56,000 Unspecified 04/28/96 908/1,466 no value
Chromium (Hexavalent) 790 USGS-53 07/10/95 101/166 100 (RMEG)
Lead 118,000 Unspecified Perched 12/01/98   15 (EPA Action Level)
Manganese 237,000 Unspecified Perched 12/01/98 629/1,249 500 (RMEG)
Mercury (Metallic) 394 TRA 02/13/91   no value
Nickel 12,200 Unspecified Perched 12/01/98 303/1,028 700 (RMEG)
Nitrate 790,000 Unspecified 01/25/91 414/456 10,000 (MCL)
Thallium 197 Unspecified 07/03/90 48/997 2 (MCL)

Sources: ATSDR 2000; USGS 1997.

Key: CREG = ATSDR's cancer risk evaluation guide; CEMEG = ATSDR's chronic environmental media evaluation guide; CV = comparison value IEMEG = ATSDR's intermediate environmental media evaluation guide; GWM = groundwater monitoring well; MCL = EPA's maximum contaminant level; ppb = parts per billion; RBC = EPA Region 3's risk-based concentrations; RMEG = ATSDR's reference dose media evaluation guide.

Note: Maximum concentrations were detected in groundwater samples from the Snake River Plain Aquifer unless otherwise specified as collected from the perched aquifer.


Table A-2. Maximum Concentration of Radionuclides in On-Site Groundwater Monitoring Wells
Radionuclide Groundwater Monitor Well Groundwater Monitor Well-Perched Comparison Values (pCi/L)
Conc. pCi/L (Bq/L) Sample Location Sample Date Conc. pCi/L (Bq/L) Sample Location Sample Date Value Type
Radioactivity
Gross alpha 4,700 (173.9) INTEC 12/93 8.3 (0.2) INTEC 10/94 15 EPA MCL
Gross beta 949,000 (35,113) INTEC 12/93 148 (5.7) TRA 5/99 50 EPA MCL
Specific Radionuclide
Cesium-137 2,240 (82.8) TAN 7/92 nd     200 EPA MCL
Cobalt-60 1,390 (51.4) TAN 11/94 nd     100 EPA MCL
Iodine-129 17 (0.6) RWMC 4/96 11.8 (0.4) INTEC 12/95 1 EPA MCL
Radium-226 190 (7) TAN 9/97 396 (14.6) TRA 7/97 5 EPA MCL
Strontium-90 516,000 (19,092) INTEC 12/93 179 (6.6) TRA 7/93 8,000 ATSDR RMEG
Tritium 75,500 (2,793.5) INTEC 1/95 746,000 (27,602) TRA 10/93 20,000 EPA MCL
Uranium (Total) 49 (1.8) RWMC 4/97 41.6 (1.6) RWMC 11/99 30 EPA MCL

Source: ATSDR 2000.

Key: Bq/L = becquerel per liter; MCL = EPA's maximum contaminant level; nd = not detected; pCi/L = picocuries
per liter; RMEG = ATSDR's reference dose media evaluation guide.

Note: Uncertainty values were not provided in FFIMS data set (ATSDR 2000).


Table A-3. Maximum Concentration of Non-Radiological Contaminants in On-Site Surface Soil
Non-Radiological Contaminant Concentration (ppm) Comparison Value (ppm)
Maximum Date Value Type
Metals
Arsenic 13.8 1/13/94 0.5 CREG
Cadmium 11.2 4/27/93 10 EMEG
Mercury 233 9/28/94 23 SSL
Semivolatile Organic Compounds
Benzo(a)pyrene 1 6/22/99 0.78 CREG
di(2-Ethylhexyl)phthalate 110 3/12/97 50 CREG
Explosives
2,4,6-Trinitrotoluene 79,000 6/1/99 20 CREG
Polychlorinated Biphenyls
Aroclor 1254 4.3 7/2/98 1 EMEG
Aroclor 1260 290 3/12/97 2.9 RBC

Source: ATSDR 2000.

Key: CREG = ATSDR's cancer risk evaluation guide; EMEG =ATSDR's environmental media evaluation guide; ppm = parts per million; RBC = EPA Region 3's risk-based concentration; SSL = EPA's soil screening level.


Table A-4. Maximum Radionuclide Concentrations in On-Site Surface Soil
Radionuclide Concentration pCi/g (Bq/kg) Estimated Dose mrem (mSv)
Maximum Location Date
Radioactivity
Gross alpha 330 (12,210) TSF 6/93 no value
Gross beta 25,600 (947,200) TSF 6/93 no value
Specific Radionuclides
Americium-241 3,200 (118,400) TRA/NSA 5/94 888 (8.88)
Cesium-137 30,400 (1 x106) TSF 6/93 65,238 (652)
Cobalt-60 570 (21,090) TRA/NSA 5/94 72 (7.17)
Lead-210 2.22 (6.66) SPERT 8/92 30 (2.96)
Plutonium-238 25.4 (939) EBR 5/95 7 (0.0733)
Plutonium-239 36 (1,332) EBR 4/94 11 (0.108)
Plutonium-239/240 5.1 (188.7) INTEC 8/93 2 (0.0162)
Radium-226 11.9 (440.3) ARA 7/97 251 (2.51)
Strontium-90 38,000 (1 x106) TRA/NSA 5/94 632,700 (6,330)
Thorium-230 1.63 (60.31) RWMC 5/92 13 (0.13)
Thorium-232 2.13 (78.81) TRA/NSA 5/94 70 (0.7)
Thorium-234 48 (1,776) CFA 7/95 8 (0.0799)
Uranium 35 (1,295) CFA 7/95 6 (0.0583)
Uranium-234 22.6 (836) CFA 7/95 4 (0.0401)
Uranium-235 15 (555) BORAX 10/95 6 (0.055)

Source: ATSDR 2000.

Key: Bq/kg = becquerel per kilogram; pCi/g = picocuries per gram; mrem = millirems; mSv = Millisieverts.

Note: Uncertainty values were not provided in FFIMS data set (ATSDR 2000).


Table A-5. Geometric Mean Concentration of Select Radionuclides in On-Site Surface Soil
Radionuclide Concentration pCi/g (Bq/kg) Estimated Dose mrem (mSv)
Geometric mean Geometric Standard Deviation Mean Dose 95% Upper Limit
Americium-241 0.17 (6.29) 13.9 0 (0.000472) 8 (0.0776)
Cesium-137 2.45 (90.65) 10.1 5 (0.0526) 49 (0.486)
Radium 1.94 (71.78) 1.56 41 (0.409) 107 (1.07)
Strontium-90 2.6 (96.2) 6.73 43 (0.433) 267 (2.67)

Source: ATSDR 2000.

Key: Bq/kg = becquerel per kilogram; pCi/g = picocuries per gram; mrem = millirems; mSv = Millisieverts.

Note: Uncertainty values were not provided in FFIMS data set (ATSDR 2000).


Table A-6. Maximum Concentration of Non-Radiological Contaminants in On-Site Air
Non-Radiological Contaminant Concentration (µg/m3) Comparison Value (µg/m3)
Maximum Location Value Type
1,1,1-Trichloroethane 136,000 RWMC 10,800 AEMEG
1,1,2,2-Tetrachloroethane 151,000 RWMC 2,800 IEMEG
1,1,2-Trichloro-1,2,2-Trifluoroethane 23,000 RWMC 0.11 RBC
1,1-Dichloroethane 10,500 CFA 510 RBC
1,1-Dichloroethene 18,600 CFA 81 IEMEG
1,2-Dichloroethane 9,710 RWMC 2,500 CEMEG
1,2-Dichloroethene,Trans- 31.7 CFA 800 AEMEG
1,2-Dichloropropane 300 CFA 235 AEMEG
1,3-Dichloropropene, Cis- 590,000 RWMC 14 IEMEG
Benzene 147 CFA 163 AEMEG
Bromoform 26,900 RWMC 0.9 CREG
Carbon Tetrachloride 20,800,000 RWMC 1,280 AEMEG
Chlorobenzene 506,000 RWMC 62 RBC
Chloroform 3,080,000 RWMC 500 AEMEG
Dichlorodifluoromethane 10,900 CFA 180 RBC
M,P-Xylene or Total Xylenes 434,000 RWMC 4,400 AEMEG
Methylene Chloride 7,290 RWMC 2,100 AEMEG
Tetrachloroethylene 81,400 RWMC 1,380 AEMEG
Toluene 4,520 RWMC 3,800 AEMEG
Trichloroethylene 2,470,000 RWMC 10,900 AEMEG
Trichlorofluoromethane 16,900 CFA 730 RBC

Source: ATSDR 2000.

Key: CREG = ATSDR's cancer risk evaluation guide; CEMEG = ATSDR's chronic environmental media evaluation guide; IEMEG = ATSDR's intermediate environmental media evaluation guide; AEMEG = ATSDR's acute environmental media evaluation guide; ppb = parts per billion; RBC = EPA Region 3's risk-based concentrations; RMEG = ATSDR's reference dose media evaluation guide.


APPENDIX B: DEMOGRAPHIC MAPS

Demographic Variables in 1, 5, and 10 Mile Increments from Facility Buildings
Figure B-1. Demographic Variables in 1, 5, and 10 Mile Increments from Facility Buildings

Demographic Variables in 5, 10, 25, and 50 Mile Increments from Facility Buildings
Figure B-2. Demographic Variables in 1, 5, and 10 Mile Increments from Facility Buildings


APPENDIX C: INEEL WASTE AREA GROUPS

Information in this appendix comes from the year 2000 Oversight and Overview report, which is a synopsis of activities and issues related to the INEEL from the state agency charged with overseeing the site on behalf of the citizens of Idaho.

WAG 1—Test Area North (TAN) (10 OUs, 63 SWMUs)

The Test Area North (TAN) is located approximately 27 miles northeast of Central Facilities Area (CFA) at INEEL and roughly 13 miles west of the nearest community (Mud Lake, population 179). Between 1986 and 1990, the TAN supported research of the 1979 Three-Mile Island incident.

Several of the TAN facilities are used for handling, storing, examining, and conducting research and development on spent nuclear fuel. The major facilities at TAN include the following:

Contained Test Facility (CTF): The CTF is located on the west end of TAN. The mission of CTF was to perform reactor loss-of-coolant studies. After these studies were completed, the facility was decontaminated and used for decontamination and decommissioning of reactors used in the Aircraft Nuclear Propulsion Program. Currently, part of the CTF serves as an operational facility for the Specific Manufacturing Capability (SMC) project. The SMC manufactures armor assemblies for the Army's Tank Unit.

Technical Support Facility (TSF): The TSF is located in the central part of TAN and serves as the main administration, assembly, and maintenance section for TAN and houses the fire department. This area also serves as an operational facility for the SMC project.

Water Reactor Research Test Facility (WRRTF): The WRRTF is located 1.6 miles south of TSF and was originally constructed to conduct pool and table reactor experiments. Various reactor programs were conducted at WRRTF, including the Semiscale (TAN 646), Thermal Hydraulic Loss-of-Coolant Project (TAN-646), the Blowdown Facility (TAN-640), and Two-Phase Flow Loop (TAN-640) loss-of-coolant projects. The facility is currently used by the Applied Engineering and Development Laboratory to work on experimental projects.

From 1953 to 1972, low-level radioactive, chemical, and sanitary wastewater at TAN was injected into the Snake River Plain Aquifer (SRPA) through a 310-foot-deep well. After 1972, wastewater was disposed of at a 35-acre infiltration pond. During 1959-95, about 61 curies (Ci) of radioactivity was discharged in wastewater to the well and infiltration pond, or about 1.2 curie per year (Ci/yr). Of this amount, about 20 Ci was discharged to the disposal well in 1968 and 1969 in response to problems with an evaporator used to reduce the volume of liquid waste. No records are available as to the amount of radioactivity in wastewater discharged at TAN prior to 1959. No wastewater discharge was recorded for 1994-95. The primary groundwater contaminants resulting from the past wastewater disposal practices are volatile organic compounds (VOCs) and radionuclides, such as tritium, strontium-90, cesium-137, and uranium.

Groundwater beneath the TAN is contaminated primarily with VOCs that were injected in the aquifer until 1972. In-situ bioremediation is being used to convert groundwater contamination to non-hazardous compounds in the areas of highest contamination; natural attenuation is reducing VOC-contaminant concentrations at the distal portions of the plume.

WAG 2—Test Reactor Area (TRA) (13 OUs, 49 SWMUs)

The Test Reactor Area (TRA) is located in the southwestern area of the INEEL, approximately 5 miles northwest of the CFA and about 12 miles from Atomic City, the nearest community. The area was originally established in the early 1950s to conduct experiments associated with developing, testing, and analyzing materials used in nuclear and reactor applications. Since the 1950s, seven nuclear reactors have been built and operated at the TRA. The reactors and associated facilities supported research on the effects of radiation on materials, fuels, and equipment. Today, the Advanced Test Reactor (ATR) is the only active reactor at TRA, producing isotopes for medicine, research, and industry.

Starting in the 1950s, low-level radioactive, chemical, and sanitary wastewater was discharged to an injection well and various ponds. Since March 1982, this wastewater has been discharged to two cold-waste infiltration ponds. The average annual discharge during 1964-1991 to the well and the infiltration ponds was about 230 million gallons during 1964-1991 and about 195 million gallons during 1992-1995.

In 1976, DOE began a three-phase program at the TRA to reduce radioactivity in wastewater. The first phase ran from 1976 through 1980; the second phase, from 1981 to 1987. The contractor finished the final phase of the program in 1993. The volume of radioactive wastewater discharged at the TRA decreased as a result of this program. By August 1993, two lined evaporation ponds replaced the radioactive-waste infiltration ponds. The evaporation ponds keep radioactive wastewater out of the aquifer. In 1974-1979, 10% of the radioactivity in wastewater discharged was attributed to tritium; in 1980, 50% was attributed to tritium; and in 1981-1985, 90% was attributed to tritium. In 1992-1995, about 96% of the radioactivity in wastewater discharged at the TRA was attributed to tritium.

Chemical wastewater from an ion-exchange system has been discharged to a chemical-waste infiltration pond at the TRA since 1962. The average annual discharge to this pond was about 18.5 million gallons from 1962 through 1995. The average for 1992-1995 was 6.8 million gallons, 37% of the long-term average. Sulfate and sodium were the predominant constituents in the chemical wastewater. During 1992-1995, average annual amounts of about 311,000 pounds of sulfate and 168,000 pounds of sodium were discharged to the chemical-waste infiltration pond; average annual concentrations of sulfate and sodium in the wastewater were about 5,400 and 3,000 milligrams per liter (mg/L), respectively.

Cleanup of the TRA radionuclide-, heavy metal-, and VOC-contaminated soil was completed in 1999. As part of the process, an underground barrier has been used to prevent insects and burrowing animals from reaching areas of subsurface contaminated soil. Groundwater is ongoing at the TRA.

WAG 3—Idaho Nuclear Technology Engineering (INTEC) (formerly known as Idaho Chemical Processing Plant [ICPP]) (13 OUs, 66 SWMUs)

The INTEC facility is located on approximately 200 acres in the south-central part of the INEEL, about 2 miles north of the CFA and 12 miles northwest of Atomic City, population 25. The facility was used to reprocess spent nuclear fuel. The facility recovered more than $1 billion worth of uranium-235. The reprocessing mission was discontinued in 1992. In May 1998, DOE changed the name from the ICPP to the Idaho Nuclear Technology and Engineering Center (INTEC) to reflect the change in the mission from reprocessing spent nuclear fuel to fuel storage and waste treatment. Today, DOE develops technologies for treatment and disposal of high-level waste at INTEC. DOE also uses INTEC for treating high-level waste and preparation for disposal at a permanent location.

From 1952 to February 1984, the facility discharged most of its low-level radioactive, chemical, and sanitary wastewater into the SRPA through a 600-foot-deep disposal well. The average annual discharge of wastewater to the well was about 363 million gallons. Two infiltration ponds currently are being used for wastewater disposal. The first pond was completed in February 1984; the second pond, in October 1985. In general, the volumes of wastewater discharged to the well and infiltration ponds have gradually increased over the years to an average annual discharge during 1992-95 of about 570 million gallons. Tritium has accounted for more than 90% of the radioactivity in wastewater discharged at INTEC since 1970. Despite the increasing volumes of discharged wastewater, tritium concentrations decreased over time. In 1990-91, only 2.7 Ci of tritium was discharged, and during 1992 and 1995 only about 0.3 Ci was discharged. No tritium was discharged during 1989, 1993, and 1994.

Cleanup at INTEC will address soil and groundwater contamination. Heavy metals, VOCs, and radionuclides will be disposed of in an on-site RCRA-compliant disposal facility, which is in early phases of construction. Some material may be disposed of off site. Impacts to groundwater will be reduced as the wastewater disposal ponds will be taken out of service. The INTEC area housed a tank farm, where radioactive material spilled from the transfer lines. To date, a remedial investigation work plan is currently under review and the DOE plans to seal the surface of the tank farm with polyurethane to prevent surface water from trickling down into the tank area.

WAG 4—Central Facilities Area (13 OUs, 38 SWMUs)

The Central Facilities Area (CFA) is located in the south-central part of the INEEL; it serves as the operational headquarters for services at INEEL. The facilities at CFA provide craft, office, services, and laboratory functions. The Van Buren Boulevard Monitoring station is located 2.2 miles west of the junction of Van Buren Boulevard and Highway 20/26.

The principal contaminant sources at CFA consist of solid waste landfills, fleet maintenance, and sanitary sewage. There are three inactive solid waste landfills north of CFA that were closed and capped in 1996 under the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA). There is also an active solid waste landfill north of CFA that receives office and cafeteria waste. Process wastewater from laboratories, medical facilities, and equipment repair shops are all routed to the sanitary sewer system. The CFA sewage treatment plant consists of three lined ponds where biological treatment of the wastewater takes place. The effluent is then sprinkler-irrigated on the land surface.

Most radioactive wastes discharged to sewage-plant tile drain field are from production well CFA-1, which draws water from within the INTEC contaminant plume in the SRPA. Most of the radioactivity in wastewater is attributed to tritium, which accounted for 1.5 Ci/yr, or about 99.7% of the total radioactivity in wastewater in 1992-93. No wastewater discharge was recorded for 1994-95.

High levels of contamination have been confirmed at the CFA, including mercury at a wastewater pond; cesium-137 in a draining field; and lead at a transformer yard. According to the July 2000 ROD, the wastewater pond will be excavated and the material will be deposited at the INTEC disposal area; the drainfield will be capped; and the lead-contaminated soil will be sent to a facility in Utah.

WAG 5—Power Burst Facility (PBF) /Auxiliary Reactor Area (ARA) (9 OUs, 43 SWMUs)

The Power Burst Facility (PBF) is located in the south-central portion of the INEEL, about 6 miles from the CFA and 8 miles from Atomic City, population 25. The area was initially used for testing reactor transient behavior and for safety studies on light-water moderated enriched fuel systems. Five reactors were installed in four facilities at PBF. Four of the five reactors have been removed, and the fifth, the PBF reactor, has been in standby mode since 1975. In 1984 and 1985, three of the facilities were radiologically decommissioned and decontaminated and modified for new missions. The facilities are now used by Waste Management Operations for waste treatment and storage.

The Waste Experimental Reduction Facility (WERF) is used to reduce the volume of waste through sizing of metallic waste, compaction, and incineration. The Waste Reduction Operation Complex is used for storage and recovery of low-level and mixed radioactive waste. The Mixed Waste Storage Facility (MWSF) stores mixed radioactive and hazardous waste for which treatment technologies do not yet exist. There are no liquid process wastes generated by the facility. Sanitary waste is discharged to drain fields. Gaseous effluents from the incineration of low-level radioactive waste are discharged through the WERF stacks.

The ARA, formerly referred to as the Army Reactor Area, is also located on less than 40 acres in the south-central portion of the INEEL. The ARA reactor was active from 1957 to 1965 for use as a power source at remote military bases. Use of the ARA facilities has been minimal since the Army Reactor Program was phased out in 1965, and essentially no activities have been undertaken there since 1988. The ARA facilities are currently being decontaminated and dismantled. The Stationary Low-Power Reactor No. 1 (SL-1) burial ground is also located at ARA. The burial ground contains debris produced by a nuclear accident and steam explosion at the SL-1 reactor during maintenance operations on January 3, 1961. The SL-1 burial ground was capped and fenced in 1996.

Radionuclide, heavy metal, and VOC contamination has been confirmed at tank sites, in the soil, and/or at wastewater ponds at PBF/ARA. A ROD signed in January 2000 outlines measures to remove the contaminated soil and contaminated waste in the tank farms and ponds by June 2004.

WAG 6—Experimental Breeder Reactor-1/Boiling Water Reactor Experiment (5 OUs, 20 SWMUs)

The Experimental Breeder Reactor No. 1 (EBR-I) consists of the reactor building and annex (EBR-601), situated on approximately 10 acres of land located about 6 miles southwest of the CFA and 15 miles northwest of Atomic City. EBR-I was constructed in 1949 and the early 1950s; it was the first reactor in the world to generate usable amounts of electricity. Today, EBR-I is designated a Registered National Historical Landmark to mark the location where several reactor cores were tested.

WAG 7—Radioactive Waste Management Complex (RWMC) (14 OUs)

The Radioactive Waste Management Complex (RWMC) occupies 187 acres 7 miles southwest of CFA and 14 miles northwest Atomic City. The RWMC was established in 1952 as a controlled area for disposal of solid radioactive wastes. Since 1954, the facility has also received defense wastes for storage. Several research and development projects dedicated to shallow land burial technology and alternate ways of removing, reprocessing, and repackaging transuranic wastes are also conducted at the facility.

The RWMC is subdivided into three primary zones as follows:

Administrative Area: Office buildings and equipment maintenance facilities are in the Administrative and Operations Area, which occupies approximately 33 acres.

Subsurface Disposal Area (SDA): The SDA is a fenced 97-acre facility dedicated to the permanent disposal of low-level beta, gamma, and non-retrievable transuranic waste (buried prior to 1970) that is contaminated with mixed fission products and hazardous constituents. Major features at the SDA include pits, trenches, and soil vaults in which waste was buried, and Pad A, which received low-level waste, primarily nitrate salts, from off-site generators. An area in the northeast corner of the SDA, Pit 9, is to be remediated under CERCLA.

Transuranic Storage Area (TSA): The TSA is a 57-acre fenced facility dedicated to storing contact- and remote-handled solid transuranic wastes. The wastes stored at TSA included transuranic (e.g., plutonium) and intermediate-level waste. Major facilities at the TSA include the Type I and Type II storage buildings, TSA-1/TSA-Retrieval, TSA-2, and TSA-3. Within the TSA-2 and TSA-3 are air-support structures and the Stored Waste Examination Pilot Plant.

Solid and liquid radioactive and chemical wastes have been buried in trenches and pits at the SDA at the RWMC since 1952. About 550 Ci of plutonium-238; 21,000 Ci of plutonium-239; 4,900 Ci of plutonium-240; 165,000 Ci of plutonium 241; and 51,000 Ci of americium-241 were buried in the trenches between 1954 and 1970. An estimated 88,400 gallons of other waste were buried before 1970, including about 24,400 gallons of carbon tetrachloride; 39,000 gallons of lubricating oil; and about 25,000 gallons of other organic compounds, including 1,1,1-trichoroethane, trichloroethylene, perchloroethylene, toluene, and benzene. Before 1970, little or no sediment was retained between the evacuation bottoms and the underlying basalt. Since 1970, a layer of sediment has been added to inhibit downward migration of waste constituents. Sanitary sewage at the facility is discharged to a lined evaporation pond.

Various agencies are involved in cleaning up contaminated groundwater and soil at the RWMC. Since 1996, DOE has been using vacuum pumps to remove VOCs from the vadose zone, the area between the ground surface and the SRPA. More than 50,000 pounds of VOCs has been extracted. DOE and the Idaho Department of Environmental Quality are exploring options to manage the waste in the soil so that is does not migrate down to the groundwater.

Most soil cleanup involves contamination from the large landfill DOE used for waste disposal for more than 30 years. Highly contaminated waste has been detected at Pit 9, an acre of the landfill containing transuranic waste from weapons production at the Rocky Flat Plant in Colorado. Stage I activities at Pit 9 indicate that most of the contamination is concentrated in hot spots rather than dispersed throughout the site. Stage II activities will target the hot spots, and stage III activities will remediate the entire site.

WAG 8—Naval Reactors Facility (8 OUs, 54 SWMUs)

The Naval Reactors Facility (NRF) is in the central part of the INEEL, about 8 miles north of the CFA and 16 miles northwest of Atomic City. It is operated by Bechtel Bettis, Inc., for DOE's Pittsburgh Naval Reactors Office. The facility has been used to examine spent reactor fuel from Navy reactors at the Expended Core Facility. There are also a number of prototype reactors at the facility that were used as training platforms for US Navy personnel. The prototypes have been permanently shut down.

Wastewater at the NRF is discharged to a 3-mile long industrial-waste ditch and to sewage ponds. During 1992-95, about 148 million gal/yr of wastewater was discharged to the industrial-waste ditch. Some 15 million gal/year of sewage effluent was discharged to the sewage ponds. The 1992-95 disposal rates are an increase since 1989-91, when 115 million gal/yr was discharged. Chloride, sulfate, and sodium were the predominant chemical constituents in wastewater discharged to the industrial-waste ditch.

WAG 9—Argonne National Laboratory-West (ANL-W) (4 OUs, 14 SWMUs)

The ANL-W is operated by the University of Chicago and reports to the DOE Chicago Field Office. ANL-W administratively controls an area of about 890 acres in the southeastern corner of the INEEL, while the facilities themselves cover less than 60 acres. The area is about 16 miles northeast of the CFA and the Atomic City. Over the years, the ANL-W has supported research and development efforts of liquid metal fast feeder reactor technology, spent nuclear fuel, and waste treatment technologies.

Radioactive liquid wastes are evaporated and solidified in the Radioactive Liquid Waste Treatment Facility. Process wastewater, which mainly consists of secondary loop reactor cooling water, is discharged to an infiltration pond. The Fuel Conditioning Facility and the Hot Fuel Examination Facility are the two primary air emissions sources at ANL-W.

Most of the contamination found at ANL-W is in the soil (cesium) and in wastewater ponds. DOE is exploring ways to eliminate the need for digging and off-site disposal of the contaminated soils. One option is phytoremediation, in which plants are used to take up cesium from contaminated soil.

WAG 10—Miscellaneous Units and SRPA (4 OUs, 13 SWMUs)

The experimental Field Station (EFS) was previously known as the Experimental Dairy Farm. It was a small-scale dairy farm used to study the movement of radionuclides through the entire air-vegetation-cow-milk sequence of the human food chain. The site is 6 miles north of CFA along the channel of the Big Lost River. Research on methods to provide barriers to water, small mammal, ant, and vegetation root intrusion through protective caps at waste disposal areas is currently being conducted there.

The Security Training Facility consists of two adjacent areas located approximately 2.5 miles east of CFA. This facility was formerly known as the Experimental Organic Cooled Reactor and Organic Moderated Reactor Experiment (OMRE) areas. The Experimental Organic Cooled Reactor was constructed directly northwest of the OMRE in 1962. The project was canceled prior to completion, and the area has since been used for materials storage, security force practice, and explosives testing. The facility was decontaminated and dismantled in 1979. The OMRE was designed to develop power from an organic coolant reactor. It consisted of a reactor control building, a reactor, heat exchangers, a septic system, a leach pond, and a water tank. The buildings and underground reactor were disassembled; radioactive matter was disposed at the RWMC; and uncontaminated parts were sold as scrap. The leach pond was backfilled with soil, and the entire area was revegetated with a mixture of native grasses in 1981.

Areas of INEEL have also been used by the Navy as practice artillery firing ranges. DOE has cleaned up known range locations and continues to look for shells while investigating other on-site locations.


APPENDIX D: DEMOGRAPHIC DATA

Table D-1. 2000 Demographics in the 10-mile Buffer from Site Boundary by County.
County
  Bingham Bonneville Butte Clark Jefferson
Total Population 280 110 1,936 54 1,751
Racial Characteristics
White 217 73 1,817 48 1,437
Black 0 0 9 1 2
American Indian and Alaska Native alone 8 7 20 0 8
Asian alone 3 0 9 0 7
Native Hawaiian and Other Pacific Islander alone 0 0 0 0 0
Some other race alone 50 30 51 2 282
Hispanic or Latino 72 39 90 5 340
Two or More races 3 0 29 3 17
Sensitive Populations
Children Age 6 or younger 32 17 212 6 244
Females 15- 44 51 21 339 8 343
Adults Age 65 and over 24 9 288 5 148
Other Variables
Total Housing 118 49 890 22 583
Total Age 18 and Older 198 72 1,376 34 1,024
Total younger than 18 83 38 556 20 677


APPENDIX E. COMPARISON VALUES

ATSDR scientists use comparison values (CVs) to screen environmental data that are relevant to the exposure pathways. CVs are concentrations of contaminants that are considered to be safe levels of exposure. ATSDR use CVs only to screen contaminants for further evaluation; the agency DOES NOT use CVs or the health guidance values from which they are derived to assess toxicological implications.

The derivation of a CV uses exposure assumptions resulting in values that are much lower than exposure concentrations observed to cause adverse health effects, thus ensuring that the CVs protect public health in all exposure situations. That is, if the concentrations in the exposure medium are less than the CV, the exposures cannot make people ill, and no further analysis of the pathway is required.

CVs are based on Health Guidance or regulatory doses, such as MRLs and RfDs. These doses are derived by serially applying "uncertainty factors" that can make them as much as 10,000 times lower than the lowest dose observed to cause harm, or the highest dose below that minimal toxic dose that is observed NOT to cause harm. Sometimes, in addition to up to 4 factors of 10 for uncertainty, additional "modifying factors" are applied, which can lower the advisory or regulatory values even further. ATSDR therefore has many reasons to be strongly confident that CVs derived by applying intake assumptions to advisory and regulatory doses will not understate potential for harm.

That is why, while concentrations below the CV are not expected to lead to any observable health effect, one cannot infer that a concentration greater than a CV will necessarily lead to adverse effects. In addition to default intake assumptions and uncertainty and modifying factors, site-specific environmental exposure factors (for example, duration of exposure) and activities of people that result in exposure (time spent in area of contamination) influence whether exposure to levels above the CV could lead to a health effect. Therefore, CVs are not used to predict adverse health effects.

The CVs used in this evaluation are defined as follows:

Cancer Risk Evaluation Guides (CREGs)

Estimated contaminant concentrations that would be expected to cause no more than one excess cancer in a million (10-6) persons over a 70-year life span based on a 95% maximum likelihood estimate over a 70-year life span. ATSDR's CREGs are calculated from EPA's cancer slope factors (CSFs). The CSF assumes that the dose and risk are proportional down to the last molecule or quantum of exposure, that there is no safe level (threshold), and that the slope relating dose and risk does not diminish with decreasing concentration. Although these assumptions have never been conclusively proved (and it may be beyond science ever to prove them in general, although they have been disproved for some special cases), this method allows data from observations of doses tens of thousands of times greater than those encountered from environmental contamination to be used to generate extremely protective CVs. ATSDR can be very strongly confident that people exposed to levels at or below the CREG are not expected to get cancer therefrom.

Environmental Media Evaluation Guides (EMEGs)

EMEGs are concentrations of a contaminant in water, soil, or air that are not expected to cause adverse noncancer effects over a specified duration of exposure. EMEGs are derived from ATSDR minimal risk levels by factoring in default body weights and ingestion or inhalation rates. Separate EMEGS are computed for acute (< 14 days), intermediate (15-364 days), and chronic (> 365 days) exposures for oral and inhalation routes.

Reference Dose Media Evaluation Guides (RMEGs)

RMEGs are the concentrations of contaminants in air, water or soil that correspond to EPA's reference doses of reference concentrations for that contaminant when ATSDR's default values for body weight and intake rates are taken into account.

Maximum Contaminant Levels (MCLs)

MCLs are EPA drinking water standards. MCLs are considered protective of human health over a lifetime (70 years) for individuals consuming 2 liters of water per day. MCLs are used for CVs when EMEGs and RMEGs are not available. As with other CVs, MCLs are not thresholds of toxicity.

EPA Region III Risk-Based Concentrations (RBCs)

These are used only when neither the values ATSDR derived from MRLs or RfDs and RfCs nor EPA's MCLs, nor (for this public health assessment) state of Idaho CVs are available. EPA combines reference doses and cancer slope factors (CSFs) with that agency's "standard" exposure scenarios to estimate risk-based concentrations, which are chemical concentrations based on fixed risk levels (i.e., an EPA hazard quotient of 1, or extrapolated CSF-based lifetime cancer risk of 10-6, whichever occurs at a lower concentration) in water, air, fish tissue, and soil.

References

  1. Agency for Toxic Substances and Disease Registry. Health Assessment Guidance Manual. Atlanta: ATSDR, October 1992.


  2. National Institute for Occupational Safety and Health. Pocket Guide to Chemical Hazards. Washington D.C.: Department of Health and Human Services, June 1994.

APPENDIX F. GLOSSARY OF TERMS

Absorption:
For nonradioactive chemical contaminants, the process of taking in. Substances can be taken into the body by breathing, swallowing, or skin contact and then transported by the bloodstream to distant organs and tissue. For radioactive substances, absorbed dose is the amount of energy deposited in a material by ionizing radiation. The unit of absorbed dose, the rad, is a measure of energy absorbed per gram of material. The unit used in most countries other than the U.S. is the gray. One gray equals 100 rad.


Acute:
An acute exposure over a short time, less than or equal to 14 days– usually a few minutes or hours, and can result in short-term or long-term health effects. An acute effect happens a short time (up to 1 year) after exposure.


Adverse Health Effect:
A change in body function or the structures of cells can be expected to lead to disease or health problems.


ATSDR:
Agency for Toxic Substances and Disease Registry (ATSDR). ATSDR is a federal health agency in Atlanta, Georgia that addresses issues regarding hazardous substances and waste sites. ATSDR provides information about harmful chemicals in the environment. The agency also evaluates whether people are exposed to hazardous substance, and if so, whether that exposure is harmful and should be stopped or reduced. The agency may also recommend appropriate public health actions to address community concerns and exposures.


Background Level:
An average or expected level of a chemical in the environment. Background often refers to naturally occurring or uncontaminated levels. Background radiation has a different meaning; it includes naturally occurring radiation from terrestrial and cosmic sources.


Biota:
Plants and animals within an environment. Some of these may be sources of food, clothing, or medicines for people.


Cancer:
Group of diseases which can occur when cells in the body become abnormal and grow, or multiply, out of control. A malignant growth, capable of invading surrounding tissue or spreading to other parts of the body.


Carcinogen:
Substance that may, in sufficient amounts, cause cancer. Ionizing radiations are physical carcinogens; there are also chemical and biologic carcinogens. Biologic carcinogens may be external (e.g., a virus) or internal (e.g., genetic defects).


CERCLA:
See Comprehensive Environmental Response, Compensation, and Liability Act.


Chronic:
Occurring over a long period of time (more than 1 year) (e.g., chronic exposure or a chronic effect).


Completed Exposure Pathway:
See Exposure Pathway.


Comparison Value (CVs):
The amount of a substance in air, water, food, and soil that is not expected, upon exposure, to cause adverse health effects. ATSDR uses comparison values as screening levels to exclude contaminants from further evaluation because they are not expected to cause ill health, given a standard daily intake rate and standard body weight. Comparison values are derived by applying assumptions and safety factors to values from the scientific literature on exposure and health effects. Because of the conservatism of the assumptions and safety factors, contaminant concentrations exceeding comparison values do not necessarily indicate a health hazard.


Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA):
CERCLA, also known as Superfund, was established in 1980. This act concerns releases of hazardous substances into the environment and the cleanup of these substances and hazardous waste sites. ATSDR was created by this act and is responsible for looking into health issues related to hazardous waste sites.


Concern:
Regard for or interest; worry, anxiety. Community health concerns are community members' beliefs or worries that substances in the environment might cause harm to people's health.


Concentration:
Generally, the amount of a substance contained in a given amount of another substance. For example, sea water contains a higher concentration of salt than does fresh water. Often refers to the amount of a substance present in a certain amount of soil, water, air, or food.


Contaminant:
See Environmental Contaminant.


Dermal:
Referring to the skin. For example, dermal absorption means absorption through the skin, and dermal contact means contact with the skin. (see Route of Exposure).


Dose:
There are different types of doses. The amount of a substance a person encounters in the environment (air, water, or soil) is the "exposure dose." "Absorbed dose" has different meanings for radioactive and nonradioactive substances. For nonradioactive substances, absorbed dose is the amount of a substance that actually enters the body. The dose for nonradioactive substances often takes body weight and frequency of exposure into account. There are several terms used in radiation protection to describe various aspects of radiation dose and its effects on humans; for example, see absorbed dose (within the definition of absorption) and Effective dose equivalent.


Duration:
Length of time. Duration of exposure is the length of time (days, months, years) that a person is exposed to a chemical or to radioactivity.


Effective Dose Equivalent:
The sum (expressed in sieverts) of dose equivalents for tissues multiplied by "risk weighting factors". Dose equivalents are weighted according to the relative susceptibility of different organs or tissues to radiation effects. They are the products of the absorbed doses in rads or grays and quality factors, whose value depends on the radiation. (The unit of dose equivalent is the rem. In SI units, the dose equivalent is the sievert, which equals 100 rem.).


Environmental Contaminant:
A substance present in a system (person, animal, or the environment) in amounts higher than that found in background levels, or what would be expected.


Environmental Media:
Usually refers to the air, water, and soil in which chemicals of interest are found. Sometimes refers to the plants and animals that are eaten, worn, or used medicinally by humans. Environmental Media is the second part of an Exposure Pathway.


U.S. Environmental Protection Agency (EPA):
The federal agency that develops and enforces environmental laws to protect the environment and the public's health.


Epidemiology:
The study of the different factors that determine how often, in how many people, and in which people diseases occur. Epidemiology tries to measure the strength of associations between disease and risk factors (e.g., exposures to physical, chemical, and biologic agents, smoking, or age). Although associations do not necessarily prove causation, they can help scientists design research to find causes and interventions that fight disease.


Exposure:
Coming into contact with a substance, by swallowing, breathing, or direct contact (such as through the skin or eyes). It is possible to be exposed to certain types of radioactivity by getting very close to a source without actual contact. Exposure may be short term (acute) or long term (chronic). (For the three ways people can come in contact with substances, see Route of Exposure.)


Exposure Pathway:
How a substance moves from its source (where it began) to where and how people can get exposed to the substance. ATSDR defines an exposure pathway as having 5 parts: the source of contamination; the environmental medium (soil, air, or water) in which contaminants are present or through which they migrate; a point of exposure (such as a private well); the route of exposure (ingestion, inhalation, or dermal contact); and a receptor population (people who are exposed or potentially exposed). When all 5 parts of an exposure pathway are present, it is called a completed exposure pathway. An incomplete pathway is one in which at least one of the 5 elements is missing; a potential pathway is currently incomplete, but the missing element(s) could exist if conditions change. A pathway is eliminated if at least one element cannot be present.


Frequency:
How often something (for example, exposure to a substance) happens over time (for example, every day, once a week, twice a month).


Hazardous Waste:
Substances that are no longer in use, that may have been released or thrown away into the environment and, under certain conditions, could be harmful to people who come into contact with them.


(Adverse) Health Effect:
Injury or illness that may be the result of exposure to biological, physical, or chemical agents (such as germs, radiation, or chemicals) harmful to a person's health. May include diseases, cancers, birth defects, genetic effects, and death.


High Level Waste:
Spent nuclear fuel or highly radioactive waste left over when spent nuclear fuel is reprocessed to recover usable uranium or plutonium. Reprocessing at INEEL involved dissolving the fuel in acid so that the resulting waste tends to be very acidic. Because it is highly radioactive and contains chemicals which make it hazardous, at INEEL, high level waste is also a "mixed waste." Mixed waste is regulated by DOE (for its radioactive components) and by other regulatory agencies (i.e., EPA, Idaho Department of Environmental Quality) for the hazardous part of the mixed waste.


Indeterminate Public Health Hazard:
The category is used in Public Health Assessment documents for sites where critical information is lacking (missing or has not yet been gathered) to support a judgment regarding the level of public health hazard.


Ingestion:
Swallowing (such as eating or drinking), one route of exposure by which substances can enter a person's body. Substances can get in or on food, drink, utensils, cigarettes, or hands, where they can be swallowed. After ingestion, substances may either be eliminated or be absorbed into the blood and distributed throughout the body (See Route of Exposure).


Inhalation:
Breathing. Another route of exposure. Exposure may occur from breathing contaminants in if they can be deposited in the lungs, taken into the blood, or both. Some, but not all, substances that are taken into the lungs can diffuse across the walls of the lung capillaries (tiny blood vessels) into the bloodstream. In addition, some inhaled particles can be removed from the respiratory tract before they reach the lungs by the beating of cilia (microscopic hairs on some of the respiratory tract surface cells). These particles are carried up to the back of the throat, where they are swallowed, thus entering the gastrointestinal tract. Some types of particles are then eliminated, while others may be absorbed into the body (See Route of Exposure).


Lowest Observed Adverse Effect Level (LOAEL):
The lowest dose of a substance in a study, or group of studies, that has caused any harmful health effects in the most sensitive people or animals.


Low Level Waste:
A variety of radioactive waste that is not high-level radioactive waste, uranium milling residues, or transuranic waste. Because of its catch-all category, types of low level waste are diverse. It includes radioactive materials from various processes, as well as supplies and equipment contaminated with radioactive materials.


Malignancy:
A cancerous disease or growth. See Cancer.


Minimal Risk Level (MRL):
An estimate of daily human exposure to a substance that is likely to be without an appreciable risk of adverse, noncancer effects over a specified duration of exposure. MRLs are derived when reliable and sufficient data exist to identify the target organ(s) of effect or the most sensitive health effect(s) for a specific duration via a given route of exposure. MRLs have been derived for acute, intermediate, and chronic duration exposures by the inhalation and ingestion routes. MRLs can be derived for dermal exposures, but none are currently available. An MRL should not be used as a predictor of adverse health effects.


National Priorities List (NPL):
The Environmental Protection Agency's (EPA) listing of Superfund hazardous waste sites that are most in need of cleanup. These sites have undergone preliminary assessment and site inspection to determine which locations pose immediate threats to the environment or to people living or working near the releases. Some sites on the NPL also have exposed populations in the past.


No Observed Adverse Effect Level (NOAEL):
The highest dose of a substance (below the lowest LOAEL) in a study, or group of studies, that did not cause harmful health effects in the most sensitive people or animals.


No Apparent Public Health Hazard:
Category used in ATSDR's Public Health Assessment documents for sites where exposure to site-related substances might have occurred in the past or is still occurring, but the exposures are not at levels expected to cause adverse health effects.


No Public Health Hazard:
Category used in ATSDR's Public Health Assessment documents for sites where no exposure to site-related hazardous substances exists.


Plume:
An area of contaminants in a particular medium, such as air or groundwater, moving away from its source in a long band or column. A plume can be a column of smoke from a chimney or an area containing substances moving with groundwater or surface water.


Point of Exposure:
Place where someone can come into contact with a contaminated environmental medium (air, water, food or soil). Examples include an area of a playground with contaminated dirt; a contaminated spring used for drinking water; fruits or vegetables grown in contaminated soil; or a backyard area where someone might breathe contaminated air.


Population:
A group of people living in a certain area; or the number of people in a certain area.


Potentially Responsible Parties (PRP):
Superfund Enforcement Tracking System contains names of individuals or companies that have been notified by the EPA via either a general notice letter or a special notice letter from the site lead agency indicating that they are potentially responsible for cleanups and other response costs at Superfund sites. The Superfund Enforcement Tracking System (SETS) was created by the EPA to track the identification of PRPs at both NPL and non-NPL sites. SETS represents preliminary findings on the identification of PRPs and does not constitute a final determination concerning the liability of any party for the hazard or contamination at any CERCLA site.


Public Health Assessment (PHA):
A process generating a report or document (or the report itself) describing substances at a hazardous waste site. The process investigates whether people could be harmed from exposure to those substances. The PHA also tells if possible further public health actions are needed.


Public Health Hazard:
The category is used in PHAs for sites that have certain physical features or evidence of chronic, site-related exposure to hazardous substances that could result in adverse health effects.


Public Health Hazard Conclusion Category:
One of four levels of hazard attributed to a site to tell whether people could be harmed by conditions present at the site. Each is defined in this Glossary. Listed in decreasing severity, the categories are:
Receptor Population:
People who live or work in the path of one or more substances and who could be exposed to them (See Exposure Pathway).


Reference Dose (RfD):
An estimate, with uncertainty factors included, of the daily, lifetime exposure of human populations to a possible hazard that is not expected to harm a person.


Route of Exposure:
The way a substance gets on or into the body. There are three primary routes of exposure: inhalation (breathing), ingestion (eating or drinking), and dermal (skin) contact (e.g., through bathing or other skin contact with a substance).


Safety Factor:
Used by some agencies in place of the term Uncertainty Factor preferred by ATSDR. When scientists don't have enough information to decide for certain if an exposure will cause harm to people, they use safety factors, uncertainty factors, and formulas in place of the information that is not known. These factors and formulas can help determine (within a wide margin of safety) the amount of a substance that is not likely to harm people.


Sample:
A small amount selected from a larger amount, chosen to represent the larger amount. The sample may be a small amount of soil or water taken from an area to analyze for contamination and learn the level of contamination in the area of concern. Or it could be a few dozen people chosen from among hundreds near a site and queried or tested to learn the opinions or health status of nearby residents in general.


Sample Size:
How much (e.g., soil or water or people) is in the selection chosen as representative of the larger amount (e.g., the area of concern, or all the people living near the site). The larger the selected sample, and the closer its quantity is to the larger amount sampled, the more similarity we may expect from the information gained from studying the small amount to the information that would be gained from studying the larger amount it was taken from.


Source (of Contamination):
The place where a substance comes from (such as a landfill, a pond, a creek, an incinerator, a tank, or a drum). Contaminant source is the first part of an exposure pathway.


Spent Nuclear Fuel:
Spent nuclear fuel is created when fuel rods containing uranium are placed in a nuclear reactor. The reaction of uranium atoms splitting produces energy and new elements, such as cesium and strontium, and transuranic elements like plutonium and americium. Over time, the fuel becomes less efficient, or spent, and must be removed. INEEL still receives shipments of spent nuclear fuel from many sources, so the inventory of spent nuclear fuel at INEEL continues to increase every year.


Statistics:
The mathematics of the collection, organization, and interpretation of data.


Superfund:
Another name for the Comprehensive Environmental Response, Compensation, and Liability Act of 1980 (CERCLA), which created ATSDR. A Superfund site is on the list of hazardous waste sites (see NPL) maintained by the EPA because these sites are the most in need of clean-up.


Superfund Amendments and Reauthorization Act (SARA):
The 1986 legislation that broadened ATSDR's responsibilities in the areas of public health assessments, establishment and maintenance of toxicologic databases, information dissemination, and medical education.


Toxic:
Harmful. Almost any substance, even pure water, can be toxic at a large enough dose (amount). The dose is what determines the potential harm of a substance and whether it would cause someone to get sick.


Toxicology:
The study of the harm, injury, or illness that substances can cause to living things. Topics studied include the substances causing the harm, how much of the substances are needed to cause harm, how the harm is caused, how to prevent the harm, and how to heal the harm.


Transuranic Waste:
A specific type of radioactive waste that is produced from processing nuclear waste. Transuranic refers to the heaviness of the element. Transuranic elements are those with atomic numbers greater than that of uranium (92), such as plutonium and americium, that are created during nuclear reactor operations. Certain transuranic elements are used in nuclear weapons or consumer products. The remaining unusable material is considered transuranic waste. Special disposal considerations must be taken with transuranic waste because the elements have long radioactive half-lives and emit alpha radiation.


Tumor:
Abnormal growth of tissue or cells that have formed a lump or mass.


Uncertainty Factor:
Used by ATSDR and EPA in place of the term Safety Factor preferred by some other agencies. When scientists don't have enough information to decide for certain if an exposure will harm people, they use uncertainty factors, safety factors, and formulas in place of the information that is not known. These factors and formulas can help determine (within a wide margin of safety) the amount of a substance that is not likely to harm people.


Urgent Public Health Hazard:
Category used in ATSDR's Public Health Assessment documents for sites that have certain physical features or evidence of short-term (less than 1 year), site-related exposure to hazardous substances that could result in adverse health effects and require quick intervention to stop people from being exposed.

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