The ESER program samples precipitation, surface water, and drinking water. Monthly composite precipitation samples are collected from Idaho Falls and the Central Facilities Area (CFA) on the INEEL. Weekly precipitation samples are collected from the Experimental Field Station (EFS) on the INEEL. Surface and/or drinking water are sampled twice each year at 19 locations around the INEEL. This occurs during the second and fourth quarters. The results of the second quarter sampling are reported here.
Precipitation samples are gathered when sufficient precipitation occurs to allow for the collection of the minimum sample volume of approximately 20 mL. Samples are taken of monthly composites from Idaho Falls and CFA, and weekly from the EFS. Precipitation samples are analyzed for tritium. Storm events in the second quarter of 2003 produced sufficient precipitation to yield 13 samples – two from CFA, three from Idaho Falls, and eight from Idaho Falls.
No tritium was measured above the 3s value in any of the samples collected during the second quarter 2003. Data for all second quarter 2003 precipitation samples collected by the ESER Program are listed in Table C-6 (Appendix C).
Thirteen drinking water samples and one duplicate were collected from selected taps throughout southeast Idaho (Figure 11). Samples were analyzed for gross alpha, gross beta, and tritium (3H).
None of the samples exceeded their 3s values for gross alpha or tritium.
Of the fourteen drinking water samples collected, all but four samples (Arco, Carey, Howe, and Mud Lake) exceeded their 3s value for gross beta (Table 2). The EPA Safe Drinking Water Act (SDWA) limits gross beta in drinking water based on an annual exposure of 4 mrem/yr. Since data are reported from the laboratory as a concentration (i.e., pCi/L) a screening concentration of 50 pCi/L is used to meet this level (Appendix B-1). The maximum concentration of gross beta detected was once again from Minidoka and was lower than the SDWA screening value. Levels of gross beta observed in drinking water are not unusual given the basaltic terrain (USGS 1991). All values are similar to those recorded in previous years, and are well below the levels outlined for drinking water protection (Table B-1). All drinking water sample results may be found in Appendix C, Table C 7.
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|
Sample Resultsa |
Limits for Comparisona |
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|
Location |
Result ± 1s |
MDC |
SDWAb |
DOE DCGc |
||
|
Aberdeen |
5.24 |
± |
0.94 |
2.66 |
50 |
100 |
|
Atomic City |
3.25 |
± |
0.82 |
2.45 |
50 |
100 |
|
Fort Hall |
9.59 |
± |
1.03 |
2.60 |
50 |
100 |
|
Idaho Falls |
3.01 |
± |
0.82 |
2.52 |
50 |
100 |
|
Minidoka |
3.57 |
± |
0.84 |
3.03 |
50 |
100 |
|
Monteview |
9.72 |
± |
1.17 |
2.51 |
50 |
100 |
|
Moreland |
8.36 |
± |
1.07 |
2.82 |
50 |
100 |
|
Mud Lake (duplicate) |
4.87 |
± |
0.83 |
2.35 |
50 |
100 |
|
Roberts |
4.38 |
± |
0.87 |
2.51 |
50 |
100 |
|
Shoshone |
4.09 |
± |
0.84 |
2.45 |
50 |
100 |
|
a. All values shown are in picocuries per liter (pCi/L). b. SDWA = Safe Drinking Water Act. c. DCG – Derived concentration Guide. |
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Five surface water samples and one duplicate sample were collected from locations throughout southeast Idaho and were analyzed for tritium, gross alpha, and gross beta. None of the samples had measurable tritium (all results were less than 3s). Three samples were greater than their respective 3s values for gross alpha activity.
Four of six surface water samples were greater than their associated 3s values for gross beta (Table 3). Even at reported levels, the gross beta values are lower than the SDWA screening value of 50 pCi/L and the DCG values (Table B-1).
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|
|
Limits for Comparisona |
|
|
Location |
Result ± 1s |
SDWA |
DOE DCG |
|
Bliss (Bliss Boat Dock) |
5.32 ± 0.95 |
50 |
100 |
|
Buhl (Clear Spring) |
4.47 ± 0.92 |
50 |
100 |
|
Twin Falls (Alpheus Spring) |
8.01 ± 1.00 |
50 |
100 |
|
Twin Falls (duplicate) |
5.38 ± 0.97 |
50 |
100 |
|
a. All values shown are in picocuries per liter (pCi/L). |
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The presence of gross alpha and gross beta in surface water (particularly the springs) is typically related to dissolution of naturally occurring radionuclides (i.e., uranium, radium, potassium) by groundwater as it flows through the surrounding basalts (USGS, 1991). Levels of gross alpha and gross beta in all samples are similar to results from recent years. All gross alpha and gross beta results can be found in Appendix C, Table C-7.