ML083400070

PINGP License Renewal: Wisconsin Department of Health Prairie Island Environmental Survey 2006. Reference 2008c

ML083400070
Person / Time
Site:	Prairie Island
Issue date:	10/24/2008
From:	State of WI, Dept of Health Services
To:	Office of Nuclear Reactor Regulation
References
Download: ML083400070 (3)

Text

Page 1 of 8 WISCONSIN DEPARTMENT OF HEALTH SERVICES Radiation About DHS Topics A - Z Programs & Services Partners & Providers Reference Center Links:

Environmental Monitoring Radon Mammography Tanning X-ray Radioactive Materials Radiation Protection Publications:

Notice to Employees Occupational Exposure Record State of Wisconsin - 2006 Prairie Island Environmental Radioactivity Survey Wisconsin Department of Health Services Division of Public Health Bureau of Environmental Health Radiation Protection Section P.O. Box 2659 Madison, Wisconsin 53701-2659 Table of Contents Introduction WI DHS Prairie Island Environmental Monitoring Sampling Program http://dhs.wisconsin.gov/dph_beh/EnvMonitoring/PrairieIsland/2007/PIsl2Survey06.htm 12/5/2008

Page 2 of 8 samples of air, precipitation, ambient gamma radiation (TLD),

surface water, fish, soil, milk, well water and vegetation that are collected from selected locations at planned sampling intervals.

Table 1 is a listing of sampling sites and includes a description, direction and distance from the monitored power plant. Table 2 provides a listing of types of samples collected, sites where samples are collected, the number of samples collected, number of samples that were missed and a listing of the required analyses. Table 3 provides an explanation of missing samples or non-routine sample analyses. Figure 1 is a map showing the location of each environmental sampling site.

Program Modifications There were no program modifications for 2006.

Laboratory Services and Quality Assurance The analysis of the samples is performed under contract with the State Laboratory of Hygiene (SLH). SLH maintains a quality assurance program. Analytical procedures provide for routine replicate analyses to verify methods and instrument operation.

Traceable sources are used to regularly calibrate the counters and daily performance checks are made between calibrations. In addition, quality control charts are maintained on the counters.

SLH participates in the Environmental Resource Associates Proficiency Testing program and has performed satisfactorily over th t i d P fi i t ti lt il bl f th http://dhs.wisconsin.gov/dph_beh/EnvMonitoring/PrairieIsland/2007/PIsl2Survey06.htm 12/5/2008

Page 3 of 8 is the "a priori" lower limit of detection as defined above, LLD as picocuries per unit mass or volume, is the standard deviation of the background counting rate sb or of the counting rate of a blank sample as appropriate, as counts per minute, E is the counting efficiency, as counts per disintegration, V is the sample size in units of mass or volume, 2.22 is the number of disintegrations per minute per picocurie, Y is the fractional radiochemical yield, when applicable, S is the self-absorption correction factor, is the radioactive decay constant for the particular d

radionuclide, and for environmental samples is the elapsed time between t sample collection, or end of the sample collection period, and time of counting.

Typical values for E, V, Y and dt have been used to calculate the LLD.

Reporting of Sample Analysis Results Results for specific analyses will be reported as either a less than (<) value or an actual activity value. The reporting of results in Table 4 under the heading Range and in Tables 5-14 are a posteriori calculations based on the actual analysis performed using the actual sample values for E, V, Y and dt. Typically the reported less than (<) results are lower than the required WI DHS LLD indicating that the required WI DHS LLD has been met.

An actual activity value will be accompanied by an uncertainty term for that analysis. The uncertainty term is a plus or minus counting uncertainty term at the 2 sigma (95%) confidence interval and is printed as (+- or +/-). Examples and explanations of data reporting are:

Example Nuclide Activity reported 1 137Cs < 10 pCi/liter 2 137Cs 15 + 3 pCi/liter In example 1 we can be 95% confident that the sample activity, if any, is less than the LLD of 10 pCi/liter. In example 2 we can be 95% confident that the actual sample activity is greater than the LLD for that analysis and is between 12 and 18 pCi/liter.

Results And Discussion Air Particulate http://dhs.wisconsin.gov/dph_beh/EnvMonitoring/PrairieIsland/2007/PIsl2Survey06.htm 12/5/2008

Page 4 of 8 A summary of reported activities by WI DHS for air particulate samples is included in Table 4. Results from the individual sample analyses are listed in Tables 5-6.

From the individual activities or quarterly averages for gross beta activities it may be noted that there are no significant differences between sites at different distances from the Prairie Island facility.

With no significant difference with distance from the Prairie Island site, an increase in gross beta activity attributable to the Prairie Island plant operation is not evident.

The gamma isotopic analysis of the quarterly air particulate filter composites detected only small amounts of the radioisotopes listed in Table 4. Beryllium-7 (7Be), detected in all composites, is a naturally occurring radioisotope that is constantly produced through nuclear reactions between cosmic rays and nuclei in the atmosphere and is detected in air composites from other areas of the state.

Influence by the Prairie Island nuclear generating facility on air quality is not evident from air particulate analysis.

Air Iodine A summary of reported activities by WI DHS for air iodine samples is included in Table 4. Results from the individual sample analyses are listed in Table 5.

Air iodine measurements were all below the LLD of 0.07 pCi/m3 for all sites.

Direct Radiation - Thermoluminescent Dosimeters (TLD's)

A summary of reported activities by WI DHS for direct radiation is included in Table 4. Results from the individual sample analyses are listed in Table 7.

Direct radiation (TLD) data for 2006 from the WI DHS network was comparable for all sites. Significant differences in exposure were not noticed at different distances from the Prairie Island nuclear facility. The average quarterly exposure from the ten sites located within Wisconsin was 15.5 +/- 2.0 milliroentgens. The average quarterly exposure for 2006 is at background levels and is comparable to other areas within Wisconsin.

Precipitation A summary of reported activities by WI DHS for precipitation is included in Table 4. Results from the individual sample analyses are listed in Table 8.

The gross beta activity in precipitation was within the normal range of activity when compared to previous years data.

http://dhs.wisconsin.gov/dph_beh/EnvMonitoring/PrairieIsland/2007/PIsl2Survey06.htm 12/5/2008

Page 5 of 8 Surface Water http://dhs.wisconsin.gov/dph_beh/EnvMonitoring/PrairieIsland/2007/PIsl2Survey06.htm 12/5/2008

Page 6 of 8 Analysis of the vegetation samples showed no unusual activities.

The gamma isotopic analysis detected only small amounts of the 7

http://dhs.wisconsin.gov/dph_beh/EnvMonitoring/PrairieIsland/2007/PIsl2Survey06.htm 12/5/2008

Page 7 of 8 http://dhs.wisconsin.gov/dph_beh/EnvMonitoring/PrairieIsland/2007/PIsl2Survey06.htm 12/5/2008

Page 8 of 8 Back to top l Contact us l Disclaimer l Employment l Privacy notice l Site feedback Protecting and promoting the health and safety of the people of Wisconsin The Official Internet site of the Wisconsin Department of Health Services http://dhs.wisconsin.gov/dph_beh/EnvMonitoring/PrairieIsland/2007/PIsl2Survey06.htm 12/5/2008