Third Quarter 2006
INL Quarterly Site Environmental Report
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S.M. Stoller Corporation
Environmental Surveillance, Education and Research Program
ISSN NUMBER 1089-5469
Stoller-ESER-103
Idaho National Laboratory Offsite Environmental
Surveillance Program Report:
Third Quarter 2006
July 2007
Contributors:
Marilyn Case, Russ Mitchell
Program conducted for the U.S. Department of Energy, Idaho Operations Office
Under Contract DE-AC07-06ID14680
By the S.M. Stoller Corporation,
Environmental Surveillance, Education and Research Program
Douglas K. Halford, Program Manager
120 Technology Drive, Idaho Falls, Idaho 83402
www.stoller-eser.com
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Most of the radionuclides detected in any of the samples collected during the third quarter of 2006 could not be directly linked with INL activities. One quarterly composited air sample had an anomalous Americium-241 result of unknown origin. Levels of most detected radionuclides were no different than values measured at other locations across the United States or were consistent with levels measured historically at the INL. All detected radionuclide concentrations were well below guidelines set by the U.S. Department of Energy (DOE) and regulatory standards established by the U.S. Environmental Protection Agency (EPA) for protection of the public. (See Table E-1.) |
This report for the third quarter, 2006, contains results from the Environmental Surveillance, Education and Research (ESER) Program’s monitoring of the Department of Energy’s Idaho National Laboratory’s (INL) offsite environment, July 1 through September 30, 2006. All sample types (media) and the sampling schedule followed during 2006 are listed in Appendix A. Specifically, this report contains the results for the following:
Air sampling, including air filters and charcoal cartridges, atmospheric moisture, and 10 micron particulate matter (PM10);
Precipitation sampling;
Agricultural product sampling, including milk, lettuce and wheat;
Game animal sampling, including large game animals;
Gross alpha and gross beta measurements are used as general indicators of the presence of radionuclides. Gross alpha and gross beta results were found to have no discernable statistical distribution during the third quarter of 2006. Because of this, these data were statistically analyzed using nonparametric methods, including the use of the median to represent central tendency. At no time during the third quarter were weekly, monthly, or quarterly gross alpha or gross beta concentrations in air collected at Boundary locations statistically greater than corresponding data for Distant locations, as one would expect if the INL were a significant source of radionuclide contamination. There were no statistical differences between gross alpha or gross beta results when grouped by location on a quarterly basis. Statistical analysis by month also showed no statistical difference between locations for gross alpha or gross beta.
Weekly comparisons of gross alpha concentrations at Distant and
Boundary locations showed two statistical differences during the third quarter
of 2006, during the weeks of July 12 and August 30, 2006. Weekly gross beta
results were not statistically different during the third quarter of 2006.
Iodine-131 (131I) was not detected in any batch of charcoal
cartridges during the third quarter.
Selected quarterly composite filter samples were analyzed for gamma emitting radionuclides, strontium-90 (90Sr), plutonium-238 (238Pu), plutonium-239/240 (239/240Pu), and americium-241 (241Am). Cesium-137 was found near the detection limit in three samples: two collected from Craters of the Moon and one from Van Buren Gate. The samples were recounted and 137Cs was confirmed in one sample collected at Craters of the Moon and the other detected at Van Buren Gate. The detected concentration was well below the DOE Derived Concentration Guide for this radionuclide.
Twenty-four atmospheric moisture samples were obtained during the third quarter of 2006 and analyzed for tritium. Three samples from Atomic city, three samples from Blackfoot, two samples from Rexburg, and one sample from Idaho Falls exceeded their respective 3s levels. The maximum value was well below the DOE DCG for tritium in air.
The ESER Program operates three PM10 samplers for particulate sampling, one each at Rexburg, Blackfoot, and Atomic City. Sampling of PM10 is informational as no analyses are conducted for contaminants. PM10 concentrations were well below all health standard levels for all samples.
Sufficient precipitation occurred to allow collection of six samples—one from Idaho Falls, two from the Central Facilities Area (CFA), and one from the Experimental Field Station (EFS). Tritium was not detected above the 3s level in two of the samples collected at CFA and the EFS. The results were within EPA measurements.
Milk samples were collected weekly in Idaho Falls and monthly at eight other locations around the INL. All samples were analyzed for gamma-emitting radionuclides. Iodine 131 was not detected in any milk sample. Cesium-137 was found slightly above the detection limit in one weekly Idaho Falls sample. No 137Cs was found in a recount of the sample.
Six lettuce samples and a duplicate sample were collected from self-contained lettuce planters placed around the area. No sample had measurable concentrations of human-made gamma-emitting radionuclides. Strontium-90 was found exceeding the 3s value in all samples. The level found was consistent with those found in previous years and is attributed to uptake of 90Sr remaining in soil from nuclear weapons testing fallout.
In the third quarter of 2006 twelve wheat samples were collected from area grain elevators. All samples were analyzed for gamma-emitting radionuclides and 90Sr. No gamma-emitting radionuclides were detected above the 3s level in any sample. Strontium-90 was detected in one sample, collected from Idaho Falls.
No game animals were available for sampling during the third quarter.
Thirteen soil samples, including one duplicate, were collected during the third quarter. Cesium-137 was detected in all but one sample. Strontium-90 was detected in all samples. The levels were consistent with historical measurements and were likely deposited during past atmospheric nuclear weapons testing. Plutonium-238 and 241Am were detected at higher than historical levels- 238Pu in one sample collected at Blackfoot and 241Am in a sample collected at Carey. However, both samples were collected at distant locations and 241Am was not detected in a replicate Carey sample. The origin of the radionuclides is therefore not likely to be the INL and most likely due to past fallout associated with atmospheric nuclear weapons testing.
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Media |
Sample Type |
Analysis |
Results |
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Air |
Filters |
Gross alpha, gross beta |
There were no statistical differences noted for monthly or quarterly gross alpha or gross beta concentrations measured at INL, Boundary, and Distant locations. Gross alpha concentrations were statistically higher at Distant locations than at Boundary locations during the week of July 12 and higher at Distant locations during the week of August 30. Weekly gross beta results were statistically equivalent. No result exceeded the DCG for gross alpha or gross beta activity in air. |
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Gamma-emitting radionuclides, select actinides, 90Sr |
Cesium-137 was detected in three samples just above the detection limit, well below the DCG and within historical measurements. No sample had detectable concentration of 241Am, plutonium or 90Sr. |
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Charcoal Cartridge |
Iodine-131 |
No detections of 131I were made during the third quarter. |
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PM10 |
Particulate matter |
No EPA egulatory limits were exceeded. |
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Atmospheric Moisture |
Liquid |
Tritium |
Twenty-four atmospheric moisture samples were collected. Nine of the results were greater than the 3s uncertainty. No sample result exceeded the DCG for tritium in air. |
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Precipitation |
Liquid |
Tritium |
Six samples were collected. Two of these samples had tritium results greater than the 3s uncertainty but well within historical measurements. |
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Milk |
Liquid |
Iodine-131, gamma emitting radionuclides |
Iodine-131 was not found in any samples. Cesium-137 was detected in one distant sample at a value just above its detection level. A recount of the sample found no 137Cs. |
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Lettuce |
Solid |
Gamma emitting radionuclides (including 137Cs), and 90Sr |
Seven samples were collected. No manmade gamma-emitting radionuclides were found in any sample. All samples had 90Sr at a detectable level consistent with historical measurements for this isotope. |
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Wheat |
Solid |
Gamma emitting radionuclides (including 137Cs), and 90Sr |
Twelve samples were collected. No manmade gamma-emitting radionuclides were found in any sample. Strontium-90 was detected in one sample within historical levels. |
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Game Animals |
Tissue |
Iodine-131, gamma emitting radionuclides |
No game animals available for sampling during the third quarter. |
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Soil |
Solid |
Gamma emitting radionuclides, 90Sr, 241Am, and plutonium |
Cesium-137 was detected in all but one sample collected. Strontium-90 was detected in all samples. The origin of these nuclides is probably deposition of fallout from atmospheric nuclear weapons testing. Plutonium-238 was detected in one distant location sample and Americium-241 was detected in one distant sample. The origin is also likely deposition of fallout radionuclides. |