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DOE/ID-12082(04) ISSN 1089-5469
STOLLER-ESER-93

Idaho National Engineering and Environmental Laboratory Site Environmental Report
Calendar Year 2004


Environmental Surveillance, Education and Research Program

U.S. Department of Energy Idaho Operations Office
October 2005

This report was prepared for the
U.S. Department of Energy Idaho Operations Office
Under Contract DE-AC07-00ID13658
By the S. M. Stoller Corporation
Environmental Surveillance, Education and Research Program
1780 First Street
Idaho Falls, ID 83401

Contents:

• INEEL Environmental Policy
• Acknowledgements
• Preface
• References
• Executive Summary
• Helpful Information
• Acronyms
• Units

Preface

Every person in the world is exposed to ionizing radiation, which may have sufficient energy to remove electrons from atoms, damage chromosomes, and cause cancer. There are three general sources of ionizing radiation: those of natural origin unaffected by human activities, those of natural origin but enhanced by human activities, and those produced by human activities (anthropogenic).

The first general source includes terrestrial radiation from natural radiation sources in the ground, cosmic radiation from outer space, and radiation from radionuclides naturally present in the body. Exposures to natural sources may vary depending on the geographical location and altitude at which the person resides. When such exposures are substantially higher than the average, they are considered to be elevated.

The second general source includes a variety of natural sources from which the radiation has been increased by human actions. For example, radon is a radioactive gas which is heavier than air. It comes from the natural decay of uranium and is found in nearly all soils. Concentrations of radon inside buildings may be elevated because of the type of soil and rock upon which they are built (high in uranium or radon) and may be enhanced by cracks and other holes in the foundation (providing access routes for the gas). Another example is the increased exposure to cosmic radiation that airline passengers receive when traveling at normal cruising altitudes.

The third source includes a variety of exposures from human-made materials and devices such as medical x-rays, radiopharmaceuticals used to diagnose and treat disease, and consumer products containing minute quantities of radioactive materials (UNSCEAR 2000).

To verify that exposures resulting from operations at U.S. Department of Energy (DOE) nuclear facilities remain very small, each site where nuclear activities are conducted operates an environmental surveillance program to monitor the air, water, and other pathways whereby radionuclides from operations might conceivably reach workers and members of the public. Environmental surveillance and monitoring results are reported annually to DOE Headquarters.

This report presents a compilation of data collected in 2004 for the environmental monitoring and surveillance programs conducted on and around the Idaho National Engineering and Environmental Laboratory (INEEL). During 2004, the Environmental Surveillance, Education and Research (ESER) Program was performed by a team led by the S. M. Stoller Corporation. This team collected 2004 data and prepared this report. During 2004, the INEEL was operated by Bechtel BWXT Idaho, LLC (BBWI). This report refers to BBWI as the Management and Operating (M&O) contractor. The M&O organization responsible for operating each facility conducted effluent and facility monitoring. The U.S. Geological Survey performed groundwater monitoring both on and off site. The M&O contractor also conducted some onsite groundwater monitoring related to waste management, clean-up/restoration, and environmental surveillance. The National Oceanic and Atmospheric Administration collected meteorological data.

This report also contains information on nonradiological monitoring performed during the year. Results of this monitoring, both chemical (liquid effluent constituent concentrations) and physical (particulates) are presented. Nonradiological parameters monitored are those required under permit conditions or are related to material released from INEEL operations.

Argonne National Laboratory-West (ANL-W), the Naval Reactors Facility (NRF) and the Advanced Mixed Waste Treatment Project (AMWTP) maintain separate monitoring programs. Each program collects similar data as the M&O and ESER contractors, but the data are specific to these facilities. ANL-W provides its information to the ESER contractor for incorporation into this annual report. AMWTP performs limited monitoring as a best management practice, and is not presented in this report. The M&O Environmental Monitoring Unit performs all regulatory and surveillance monitoring at this facility, which is presented here. The INEEL Oversight Program, under the Idaho Department of Environmental Quality, maintained independent sample locations and analysis capabilities both on and around the INEEL in 2004.

Facilities operated under the Naval Nuclear Propulsion Program, like the NRF, are exempt from the provisions for preparing an annual site environmental report. The Naval Nuclear Propulsion Program maintains a separate environmental protection program to ensure compliance with all applicable environmental laws and regulations. Monitoring data and information specific to NRF are provided in a separate annual environmental report issued by NRF. For completeness, data from onsite monitoring programs at NRF are referenced in this report.

This report, prepared in accordance with the requirements in DOE Orders 450.1 and 231.1, is not intended to cover the numerous special environmental research programs conducted at the INEEL (DOE 2003a, 2003b).

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References

United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR), 2000, “Sources and Effects of Ionizing Radiation,” Vol. 1, UNSCEAR 2000 Report to the General Assembly with Scientific Annexes.

U.S. Department of Energy (DOE), 2003a, "Environmental Protection Program," DOE Order 450.1, January.

U.S. Department of Energy (DOE), 2003b, "Environment, Safety, and Health Reporting," DOE Order 231.1, August.

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Executive Summary

M. Case - S. M. Stoller Corporation

Each year the U.S. Department of Energy (DOE) publishes the Idaho National Engineering and Environmental Laboratory (INEEL) site environmental report to summarize environmental data, information, and regulations, and highlight major environmental programs and efforts. In summary, the results of the monitoring programs for 2004 presented in this report indicate that radioactivity from current INEEL operations could not be distinguished from worldwide fallout and natural radioactivity in the region surrounding the INEEL. Radioactive material concentrations in the offsite environment were below State of Idaho and federal health protection guidelines. Potential doses to the maximally exposed individual and to the surrounding population were estimated to be well below the applicable regulatory limit and far less than doses resulting from background radiation.

Organization of the Report
Individual chapters of the report are designed to:

• Provide an overview of the INEEL site, mission, and history (Chapter 1);
• Summarize the status of INEEL compliance with environmental regulations (Chapter 2);
• Describe major activities and milestones in environmental restoration, waste management, and other environmental programs, and review INEEL environmental surveillance programs (Chapter 3);
• Present and evaluate results of environmental monitoring of air (Chapter 4);
• Present and evaluate results of monitoring of liquid effluent, drinking water, and storm water for compliance with applicable laws, regulations, and other requirements (Chapter 5);
• Present and evaluate results of environmental monitoring of groundwater, drinking water, and surface water (Chapter 6);
• Present and evaluate results of environmental monitoring of other media (Chapter 7);
• Discuss the potential radiation dose to the public and to biota (Chapter 8);
• Describe ecological research activities that took place on the INEEL (Chapter 9); and
• Discuss programs used to ensure environmental data quality (Chapter 10).

Chapter highlights are presented below.

Introduction (Chapter 1)
The Atomic Energy Commission created what is now the INEEL as the National Reactor Testing Station in 1949 as a site to build and test nuclear power reactors. The INEEL occupies approximately 2300 km² (890 mi²) of the upper Snake River Plain in southeastern Idaho. Over the life of the INEEL, 52 types of reactors, associated research centers, and waste handling areas have been constructed and tested.

The INEEL serves as a multi-program national laboratory that delivers science and engineering solutions to the world's environmental, energy, and security challenges in four core areas:

• Science-based, engineered solutions to challenges of the DOE's mission areas, other federal agencies, and industrial clients.
• Completion of environmental cleanup at the INEEL.
• Enhancement of scientific and technical talent, facilities, and equipment to best serve national and regional interests.
• Leadership and support to the Environmental Management mission throughout the DOE complex.

There are nine primary facility areas and three smaller secondary facilities at the INEEL and in Idaho Falls. Six of the nine primary facilities and the three secondary facilities are operated by the INEEL Management and Operating (M&O) Contractor Bechtel BWXT Idaho, LLC. The University of Chicago, British Nuclear Fuels Limited, Inc., and Bechtel Bettis, Inc. operated the remaining three primary facilities at the INEEL in 2004.

Approximately 7000 people work at the INEEL, making it the largest employer in eastern Idaho and one of the top five employers in the State. The INEEL has a tremendous economic impact on eastern Idaho. The INEEL infuses more than $750 million dollars to the Idaho economy.

Environmental Compliance Summary (Chapter 2)
Table ES-1 presents a brief summary of the INEEL's status of compliance with federal acts in 2004.

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Environmental Program Information (Chapter 3)
Many environmental programs help implement the environmental compliance policy for the INEEL. Most of the regulatory compliance activity is performed through environmental monitoring programs, the recently signed Accelerated Cleanup Agreement, the Environmental Restoration Program, and the Waste Management Program.

The major objectives of the environmental monitoring programs conducted at the INEEL are to identify the key contaminants released to the environment, to evaluate different pathways through which contaminants move in the environment, and to determine the potential effects of these contaminants on the public and the environment. This is accomplished through sampling and analysis of air; surface, subsurface, and drinking water; soil; wildlife; and vegetation, as well as measurement of direct radiation. During 2004, the prime M&O contractor at the INEEL, Bechtel BWXT Idaho, LLC was responsible for onsite environmental monitoring. The Environmental Surveillance, Education and Research Program (ESER) contractor, which was a team led by the S. M. Stoller Corporation, was responsible for offsite environmental monitoring.

In May 2002, DOE, DEQ and the EPA signed a letter of intent formalizing an agreement to pursue accelerated risk reduction and cleanup at the INEEL. The intent of accelerating the cleanup of the INEEL yields two significant objectives: (1) risk reduction and continued protection of the Snake River Plain Aquifer and (2) consolidation of Environmental Management activities and reinvestment of savings into cleanup. Nine strategic initiatives were developed around these two objectives to accelerate cleanup. The INEEL made significant progress in 2004 toward accelerated cleanup.

The Environmental Restoration Program continued progress during 2004 toward final cleanup of contaminated sites at the INEEL. Since the Federal Facility Agreement and Consent Order was signed in December 1991, 22 Records of Decision (ROD) have been signed and are being implemented; three Remedial Investigation/Feasibility Studies are under development; closeout activities at Waste Area Group (WAG) 2, 4, and 8 have been completed. Only three investigations remain to be completed:

• Buried waste at the RWMC WAG 7;
• Soil contamination at the INTEC Tank Farm (WAG 3, Operable Unit [OU] 3-14;
• Snake River Plain Aquifer contamination (WAG 10, Operable Unit 10-8).

The overall goals of the Waste Management Program are to ensure that workers and the public are protected and the environment is not further impacted by waste operations at the INEEL. The Waste Management Program provides management services for facility waste streams. The following tasks were accomplished during 2004:

• Three Site Treatment Plan milestones were met.
• BNFL commenced Treatment Facility operations at the Advanced Mixed Waste Treatment facility in August 2004.
• Over 900 m³ (1,177 yd³) of mixed low-level waste was treated and disposed of in 2004.
• Approximately 6080 m³ (7,953 yd³) of legacy and newly generated waste was disposed in the subsurface disposal area (SDA) in 2004.
• The Transuranic Waste Program shipped 192 m³ (251 yd³) of transuranic waste to the Waste Isolation Pilot Plant in Carlsbad, New Mexico.
• The INEEL accelerated efforts to decontaminate, decommission, and demolish aging, unnecessary buildings and structures. Over 29,203 m² (314,338 ft²) of buildings and structures were demolished in 2004.

Environmental Monitoring Programs - Air (Chapter 4)
The INEEL environmental surveillance programs, conducted by the M&O contractor and the ESER contractor, emphasize measurement of airborne radionuclides because air transport is considered the major potential pathway from INEEL releases to receptors. The M&O contractor monitors airborne effluents at individual INEEL facilities and ambient air outside the facilities to comply with appropriate regulations and DOE orders. The ESER contractor samples ambient air at locations within, around, and distant from the INEEL.

An estimated total of 8,816 Ci of radioactivity, primarily in the form of short-lived noble gas isotopes, was released as airborne effluents in 2004. Samples of airborne particulates, atmospheric moisture, and precipitation were analyzed for gross alpha and gross beta activity, as well as for specific radionuclides, primarily tritium, strontium-90 (⁹⁰Sr), iodine-131 (¹³¹I) cesium-137 (¹³⁷Cs), plutonium-239/240 (^239/240Pu), and americium-241 (²⁴¹Am). All concentrations were well below regulatory standards and within historical measurements. Table ES-2 summarizes the results of radiological monitoring of environmental media, including air, sampled at INEEL boundary, onsite, and offsite locations.

Nonradiological pollutants, including particulates, were monitored at select locations around the INEEL. All results were well below regulatory standards.

Environmental Compliance Monitoring Programs (Liquid Effluent, Drinking Water, Surface Water) (Chapter 5)
One potential pathway for exposure (primarily to workers) to the contaminants released from the INEEL is through surface, drinking, and groundwater. The M&O contractor monitors liquid effluents, drinking water, groundwater, and storm water runoff at the INEEL to comply with applicable laws and regulations, DOE orders, and other requirements (e.g., Wastewater Land Application Permit [WLAP] requirements). Argonne National Laboratory-West and the Naval Reactors Facility conduct their own WLAP and drinking water monitoring. The ESER contractor monitors drinking water and surface water at offsite locations.

During 2004, liquid effluent and groundwater monitoring was conducted in support of WLAP requirements for INEEL facilities that generate liquid waste streams covered under WLAP rules. The WLAPs generally require compliance with the Idaho groundwater quality primary and secondary constituent standards in specified groundwater monitoring wells. The permits specify annual discharge volume and application rates and effluent quality limits. As required, an annual report was prepared and submitted to the DEQ. Additional parameters are also monitored in the effluent in support of surveillance activities. Most wastewater and groundwater regulatory and surveillance results were below applicable limits in 2004. Several metals detected in October 2004 samples taken from the INTEC New Percolation Ponds perched water compliance wells ICPP-MON-V-200 and ICPP-MON-V-212 were above their respective state of Idaho groundwater secondary constituent standards and therefore above the Wastewater Land Application Permit limits. Further evaluation indicated that the likely cause of the elevated metals were suspended solids from washed-in interbed material.

One TAN/Technical Support Facility (TSF) Sewage Treatment Plant monitoring well had concentrations of iron, manganese, and total dissolved solids that exceeded permit limits. Further evaluation is needed to determine the cause.

No EPA health-based drinking water or DOE regulatory limits were exceeded in INEEL drinking water in 2004.

Tritium continues to be measured in the groundwater under the INEEL. This radionuclide has not been detected off the INEEL since the mid-1980s. A maximum effective dose equivalent of 0.47 mrem/yr (4.7 µSv/yr), less than the 4 mrem/yr (40 µSv/yr) EPA standard for public drinking water systems, was calculated for workers at the Central Facilities Area on the INEEL in 2004.
 

As required by the General Permit for storm water discharges from industrial activities, visual examinations were made and samples were collected from selected locations. Visual examinations showed no deficiencies. As of December 2003, the DOE no longer conducts compliance activities associated with the Storm Water Pollution Prevention Plan for Industrial or Construction Activities at three INEEL facilities that do not have a reasonable potential to release storm water to U.S. waters, as determined by EPA.

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Environmental Monitoring Program - Groundwater, Drinking Water, and Surface Water (Chapter 6)
Results from a number of special studies conducted by the U.S. Geological Survey of the properties of the aquifer were published during 2004. Several purgeable organic compounds continue to be found in monitoring wells, including drinking water wells at the INEEL. Concentrations of organic compounds were below the state of Idaho groundwater primary and secondary constituent standards as well as EPA MCLs for these compounds. (Note: The MCL is used only for comparison because the MCL applies mainly to the distribution system).

Environmental Restoration groundwater monitoring continued for the Waste Area Groups on the INEEL in 2004. At Test Area North, activities continued to contain and restore groundwater contaminated with chlorinated solvents using in-situ bioremediation and pump and treat methods. At the Idaho Nuclear Technology and Engineering Center, monitoring indicates that the concentrations of most radionuclides are decreasing over time, with the possible exception of technetium-99. Monitoring at RWMC found some elevated concentrations of solvents (including carbon tetrachloride, toluene and trichloroethane, chromium, and uranium-235. Concentrations of contaminants at other Waste Area Groups were similar to expected and historical concentrations.

Drinking water samples were collected from 14 locations off the INEEL and around the Snake River Plain in 2004. One sample had measurable gross alpha, eleven samples had measurable tritium, and most samples had measurable gross beta activity. None of the samples exceeded the EPA Maximum Contaminant Level (MCL) for these constituents.

Eleven offsite surface water samples were collected from five locations along the Snake River. No sample had measurable gross alpha activity. Most samples had measurable gross beta activity, while only one sample had measurable tritium. None of these constituents were above regulatory limits.

Table ES-2 summarizes the results of radiological monitoring of environmental media, including water, collected at INEEL boundary, onsite, and offsite locations.

Environmental Monitoring Programs - Agricultural Products, Wildlife, Soil, and Direct Radiation (Chapter 7)
To help assess the impact of contaminants released to the environment by operations at the INEEL, agricultural products (milk, lettuce, wheat, potatoes, and sheep), wildlife, and soil were sampled and analyzed for radionuclides. In addition, direct radiation was measured on and off the INEEL in 2004.

Some human-made radionuclides were detected in agricultural product, wildlife, and soil samples. For the most part, the results could not be directly linked to operations at the INEEL.
Direct radiation measurements made at offsite, boundary and onsite locations (except RWMC) were consistent with background levels.

Table ES-2  summarizes the results of radiological monitoring of environmental media, including biota and soil, collected at INEEL boundary and offsite locations.

Dose to the Public and Biota (Chapter 8)
Potential radiological doses to the public from INEEL operations were evaluated to determine compliance with pertinent regulations and limits. Two different computer programs were used to estimate doses: the Clean Air Act Assessment Package, 1988 (CAP-88) computer code and the mesoscale diffusion (MDIFF) air dispersion model. CAP-88 is required by the EPA to demonstrate compliance with the Clean Air Act. The National Oceanic and Atmospheric Administration Air Resources Laboratory-Field Research Division developed MDIFF to evaluate dispersion of pollutants in arid environments such as those found at the INEEL. The maximum calculated dose to an individual by either of the methods was well below the applicable radiation protection standard of 10 mrem/yr. The dose to the maximally exposed individual, as determined by the CAP-88, program was 0.044 mrem (0.44 µSv). The dose calculated by the MDIFF program was 0.031 mrem (0.31 µSv). The maximum potential population dose to the approximately 276,979 people residing within an 80-km (50-mi) radius of any INEEL facility was 0.368 person-rem (3.7 x 10^-3 person-Sv), well below that expected from exposure to background radiation.

Potential doses to members of the public are summarized in Table ES-3.

The maximum potential individual doses from consuming waterfowl and big game animals, at the INEEL, based on the highest concentrations of radionuclides measured in samples of these animals, were estimated to be 0.005 mrem (0.05 µSv), and 0.008 mrem (0.08 µSv), respectively. These estimates are conservatively high.

Doses were also evaluated using a graded approach for nonhuman biota at the INEEL. Based on this approach, there is no evidence that INEEL-related radioactivity in soil or water is harming populations of plants or animals.

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Ecological Research at the Idaho National Environmental Research Park (Chapter 9)
The INEEL was designated as a National Environmental Research Park (NERP) in 1975. The NERP program was established in the 1970s in response to recommendations from citizens, scientists, and members of Congress to set aside land for ecosystem preservation and study. In many cases, these protected lands became the last remaining refuges of what were once extensive natural ecosystems. The NERPs provide rich environments to train researchers and introduce the public to ecological science. They have been used to educate grade school and high school students and the general public about ecosystem interactions at DOE sites; to train graduate and undergraduate students in research related to site-specific, regional, national, and global issues; and promote collaboration and coordination among local, regional, and national public organizations, schools, universities, and federal and state agencies.

Ecological research at the INEEL began in 1950 with the establishment of the long-term vegetation transect. This is perhaps DOE's oldest ecological data set and one of the oldest vegetation data sets in the West. Ecological research on the NERPs is leading to planning for better land use, identifying sensitive areas on DOE sites so that restoration and other activities are compatible with ecosystem protection and management, and increasing contributions to ecological science in general.

The following ecological research projects took place at the Idaho NERP during 2004:

• The Effect of Landscape Change on the Life History of Western Rattlesnakes;
• Factors that Influence the Road Mortality of Snakes on the Eastern Snake River Plain;
• Behavior, Dispersal, and Survival of Captive-Raised Idaho Pygmy Rabbits Released onto the INEEL in Idaho;
• Fine-scale Movement Patterns of Coyotes on the INEEL in Idaho;
• Natural and Assisted Recovery of Sagebrush in Idaho’s Big Desert;
• Phylogenetic Analysis of the Abronic ammophilia Green (Nyctaginaceae) Species Complex;
• Ecological Impacts of Irrigating Native Vegetation with Treated Sewage Wastewater;
• The Protective Cap/Biobarrier Experiment; and
• Developing Advanced Scientific Methods for Landscape Level Management of Federal Facilities.

Quality Assurance (Chapter 10)
Quality assurance and quality control programs are maintained by contractors conducting environmental monitoring and by laboratories performing environmental analyses to ensure precise, accurate, representative, and reliable results and maximize data completeness. Data reported in this document were obtained from several commercial, university, government, and government contractor laboratories. To assure quality results, these laboratories participate in a number of laboratory quality check programs.

Quality issues that arose with laboratories used by the M&O and ESER contractors were addressed with the laboratories and resolved.

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Helpful Information

M. Case - S. M. Stoller Corporation

Scientific Notation
Scientific notation is used to express numbers that are very small or very large. A very small number is expressed with a negative exponent, for example, 1.3 x 10^-6. To convert this number to the decimal form, the decimal point must be moved left by the number of places equal to the exponent (six, in this case). The number, thus, becomes 0.0000013.

For large numbers, those with a positive exponent, the decimal point is moved to the right by the number of places equal to the exponent. The number 1,000,000 can be written as 1.0 x 10⁶.

Unit Prefixes
Units for very small and very large numbers are often expressed with a prefix. One common example is the prefix kilo (abbreviated k), which means 1000 of a given unit. One kilometer is, therefore, equal to 1000 meters. Table HI-1 shows fractions and multiples of units while, Table HI-2 provides useful conversions.

Units of Radioactivity, Radiation Exposure, and Dose
The basic unit of radioactivity used in this report is the curie (abbreviated Ci). The curie is historically based on the number of disintegrations that occur in 1 gram of the radionuclide radium-226, which is 37 billion nuclear disintegrations per second. For any other radionuclide, 1 Ci is the amount of the radionuclide that decays at this same rate.

Radiation exposure is expressed in terms of the roentgen (R), the amount of ionization produced by gamma radiation in air. Dose is given in units of roentgen equivalent man (or rem), which takes into account the effect of radiation on tissues. For the types of environmental radiation generally encountered, the unit of roentgen is approximately numerically equal to the unit of rem. A person-rem is the sum of the doses received by all individuals in a population.

The concentration of radioactivity in air samples is expressed in units of microcuries per milliliter (µCi/mL) of air. For liquid samples, such as water and milk, the units are in picocuries per liter (pCi/L). Radioactivity in agricultural products is expressed in nanocuries per gram (nCi/g) dry weight. Annual human radiation exposure, measured by environmental dosimeters, is expressed in units of milliroentgens (mR). This is sometimes expressed in terms of dose as millirem (mrem), after being multiplied by an appropriate dose equivalent conversion factor.

The Système International is also used to express units of radioactivity and radiation dose. The basic unit of radioactivity is the Becquerel (Bq), which is equivalent to 1 nuclear disintegration per second. The number of curies must be multiplied by 3.7 x 10¹⁰ to obtain the equivalent number of Becquerels. Radiation dose may also be expressed using the Système International unit sievert (Sv), where 1 Sv equals 100 rem. Table HI-2 provides conversions from conventional to Système International units.

Uncertainty of Measurements
There is always an uncertainty associated with the measurement of environmental contaminants. For radioactivity, a major source of uncertainty is the inherent statistical nature of radioactive decay events, particularly at the low activity levels encountered in environmental samples. The uncertainty of a measurement is denoted by following each result with plus or minus (±) the estimated sample standard deviation, s, that is obtained by propagating sources of analytical uncertainty in measurements. Analytical uncertainties are reported as 1s in this report, unless noted otherwise, for consistency with other INEEL environmental monitoring reports.

Negative Numbers as Results
Negative values occur in radiation measurements when the measured result is less than a pre-established average background level for the particular counting system and procedure used. These values are reported as negative, rather than as "not detected" or "zero," to better enable statistical analyses and observe trends or bias in the data.

Radionuclide Nomenclature
Radionuclides are frequently expressed with the one- or two-letter chemical symbol for the element. Radionuclides may have many different isotopes, which are shown by a superscript to the left of the symbol. This number is the atomic weight of the isotope (the number of protons and neutrons in the nucleus of the atom). Radionuclide symbols used in this report are shown in Table HI-3.

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Acronyms