Second 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-99
Idaho National Laboratory Offsite Environmental
Surveillance Program Report:
Second Quarter 2006
January 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
1780 First Street, Idaho Falls, Idaho 83401
www.stoller-eser.com
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None of the radionuclides detected in any of the samples collected during the second quarter of 2006 could be directly linked with INL Site activities. Levels of 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 Site. 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 second quarter of 2006 contains results from the Environmental Surveillance, Education and Research (ESER) Program’s monitoring of the Department of Energy’s Idaho National Laboratory (INL) Site’s offsite environment, April 1 through June 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
Surface Water sampling
Drinking water sampling
Milk sampling
Large game animal sampling
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 second 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 second quarter were 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 Site were a significant source of radionuclide contamination. Gross alpha activity was greater at Distant locations, when grouped quarterly and during the months of May and June. Weekly comparisons of gross alpha concentrations at Distant and Boundary locations showed statistical differences during the weeks of April 12th, May 24th, June 14th, and June 21st. In all four cases, the Distant locations were statistically greater than the Boundary locations. These differences appear to be due to random variability in the data.
There were no statistical differences between gross beta results when grouped by location on quarterly, monthly and weekly bases.
Iodine-131 (131I) was not detected in any batch of charcoal cartridges during the second 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). No manmade gamma-emitting radionuclides were detected. Strontium-90 was detected at three locations within the range of historical measurements and well below the DOE Derived Concentration Guide (DCG).
A total of nine detections of transuranic radionuclides (two of 241Am, five of 238Pu and two of 239/240Pu) were reported for the second quarter. Detections were reported at Distant, Boundary and INL Site locations. All concentrations were near detection levels and well within historical values and below DOE DCGs. No specific source could be identified for the detected measurements and they appear to be associated with background levels of historic fallout from nuclear weapons testing.
Seven atmospheric moisture samples were obtained during the second quarter of 2006 and analyzed for tritium. Two each from Atomic City and Blackfoot, and three 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 primarily informational as no analyses are conducted for contaminants. PM10 concentrations were well below all health standard levels for all samples. The maximum 24-hour particulate concentration was 43.7 µg/m3 on May 16, 2006, at Rexburg. This is well below the EPA Air Quality Standard of 150 µg/m3.
Storm events in the second quarter of 2006 produced sufficient precipitation to
yield 10 samples –two from Idaho Falls, three from CFA, and five weekly samples
from the EFS. One of the samples, collected at the CFA, contained a detectable
concentration of tritium, within the range reported by the EPA across the
western United States.
Milk samples were collected weekly in Ucon and monthly at nine other locations
around the INL Site. All samples were analyzed for manmade gamma-emitting
radionuclides. Iodine-131 was not detected in any sample. Cesium-137 was detected
in one sample at background level. Low levels of 90Sr were found in
all samples. Tritium was detected on one of five
samples. Results were within historical measurements.
Cesium-137 was detected in the muscle tissue of the only game animal killed on an INL Site road. The detected concentration was similar to those found in both onsite and offsite tissues during recent years.
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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 weekly, monthly or quarterly gross beta concentrations measured at INL Site, Boundary and Distant locations. Quarterly and monthly (May and June) and some weekly statistical differences were found for gross alpha activity. In each case, Distant concentrations were greater than Boundary results. INL Site releases are thus not implicated. No result exceeded the DCG for gross alpha or gross beta activity in air. |
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Gamma-emitting radionuclides, select actinides (241Am, 238Pu, and 239,240 Pu), 90Sr |
Detectable 90Sr was found at three locations, well below DOE limits. Nine detections of the three actinides were reported, scattered among INL Site, Boundary, and Distant locations. The detections were well within the historical range measured for these radionuclides and well below DCGs. |
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Charcoal Cartridge |
Iodine-131 |
No detections of 131I were made during the second quarter. |
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PM10 |
Particulate matter |
Forty-five valid samples were collected from three locations. No regulatory limits were exceeded. |
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Atmospheric Moisture |
Liquid |
Tritium |
A total of 23 samples were collected. Seven of these samples had tritium results greater than the 3s uncertainty. Concentrations were consistent with those reported across the region and with previous results. |
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Precipitation |
Liquid |
Tritium |
Ten samples were collected. One of the results from CFA was greater than the 3s uncertainty. No sample result exceeded the DCG for tritium in air. |
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Drinking Water |
Liquid |
Gross alpha, gross beta, tritium |
Gross alpha activity was detected in one sample from Howe. Gross beta activity was measured in 13 of 15 samples collected (including duplicate). The maximum was well below the EPA Safe Drinking Water Act limits. Tritium was not detected in any sample. |
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Surface Water |
Liquid |
Gross alpha, gross beta, tritium |
No tritium was detected in any of the seven samples (including a duplicate) collected. Gross alpha activity was measured above the 3s values in one sample. Gross beta activity was measured above the 3s values in all samples. All concentrations were below EPA and DOE limits, and were within historical measurements. |
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Milk |
Liquid |
Iodine-131, gamma-emitting radionuclides, and 90Sr & tritium (select samples only) |
Cesium-137 was detected in one of ten samples analyzed for gamma-emitting radionuclides.. Iodine-131 was not found in any sample. Strontium-90 was detected at low levels in all five samples analyzed for 90Sr and tritium. Tritium was detected on one of five samples. Results were within historical measurements. |
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Sheep |
Tissue |
Iodine-131, gamma emitting radionuclides |
Cesium-137 was detected in one muscle sample from one sheep collected from the Northern grazing allotment. The value was within the historical range of measurements and may be attributed to fallout in the environment. |
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Game Animals |
Tissue |
Iodine-131, gamma emitting radionuclides |
Cesium-137 was found in the muscle sample from the game animal available for sampling during the second quarter. The detected value was well within the range of historical values. |
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Environmental Radiation |
TLD |
Ambient ionizing radiation |
Values were consistent with expected exposures given the altitude and location of the TLD's. There were no statistical differences between Boundary and Distant location results. |