ML20133M350
| ML20133M350 | |
| Person / Time | |
|---|---|
| Site: | Fort Saint Vrain  |
| Issue date: | 12/31/1996 |
| From: | Jerrica Johnson, Jones V, Schlieger T PUBLIC SERVICE CO. OF COLORADO |
| To: | NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM) |
| References | |
| P-97003, NUDOCS 9701220351 | |
| Download: ML20133M350 (103) | |
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16805 Wald County Road 19-1/2 Platteville, Colorado 80651-January 13,L1997 Fort St. Vrain Unit No. 1 P-97003
-U.S. Nuclear. Regulatory Commission ATTN: Document Control Desk Washington, D.C. 20555 Docket No. 50-267
SUBJECT:
1996 ANNUAL RADIOLOGICAL ENVIRONMENTAL OPERATING REPORT
& 1995 ERRATA Gentlemen:
Enclosed is a copy of the Fort St. Vrain Nuclear Station Annual Radiological Environmental Operating Report for 1996 and the Errata for Table II.B.1(d) of the 1995 Report.
This report provides summaries, interpretations, and analyses of trends of the results of the Radiological Environmental Monitoring Program for calendar year 1996. - Public Service Company of Colorado submits this report in accordance with Section 5.5.1.b of the Fort St. Vrain Decommissioning Technical Specifications.
The final radioactive effluent release from Fort St. Vrain was completed on July 3, 1996, so this report is complete for calendar
- year 1996, and is the final Radiological Environmental Operating Report for the Fort St. Vrain Nuclear Statin.
Please contact' Mr. M. H. Holmes at (303) 571-7633 if you have questions regarding the report.
Sincerely, hhAEth- W I Frederic J Borst-Decommiss oning Program Director hh l FJB:ts-Enclosure 9701220351 961231 PDR ADOCK 050002 7 l" R
___________________________________________________.__m
C January 13, 1997 P-97003 Page 2 cc: Regl'onal Administrator, Region IV Mr. Robert M. Quillin, Director Radiation Control Division Colorado Department of Public Health and Environment RCD-DO-B1 4300 Cherry Creek Drive South Denver, Colorado 80222-1530 Dr. James E.1 Johnson Department of Radiological Health Sciences MRB Building Colorado State University-Fort Collins, Colorado 80523 i
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SUMMARY
REPORT 1996 COLORADO STATE UNIVERSITY FORT COLLINS, COLORADO 80523 t____ -- _ -- _ __
Radiological Environmental Monitorier Pronram (REMP)
For the Fort St. Vrain Station Operated by Public Service Company of Colorado Summary Report for the Period January I.1996 July 11.1996 Prepared by;
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ame Date E. Johnson (
i ssor and Principal . nvestigator Colorado State University '!
Y" Vaugh'n T. Jones
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Research Associate Colorado State University Reviewed by: 0 b1f;b bF I N' W Tiiftothy Schleiger Date Senior IIcalth Physicist Public Service Company avoucwn6m nhl9s Frederick syrst Date Radiation Protection Manager Public Service Company i
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l Acknowledacments l 9
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Many persons have contributed to this project since its inception in 1970, and it is important to acknowledge their efTorts; There have been many technicians and graduate students working on this project. All have been acknowledged in previous reports, but we here thank r
them collectively.
We again thank the citizens from whose farms, homes, and ranches we collect the ;
environmental samples. Without their cooperation the project would not be possible ;
We also wish to acknowledge and thank Mr. Robert Keiss and his associates as well as.
. the Colorado Division of Wildlife, Fort Collins regional office for assisting with the fish collection. Their cooperation, equipment and expertise made the collection possible. ,
The persons in this laboratory working directly on the project during 1996 have been: }
Grant Johns Student Employee Thomas Miller Laboratory Coordinator Charles Sampier Chief Electronic Technician ,
Gerald M. Ward Professor Emeritus
- s. e i James E. Johnshn Pro esso and Project Die:ctor :
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'Vaughn T/ Jones i Research Associate :
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ii -
- TABLE OF CONTENTS Page No.
Acknowledgments ii List ofTables - iv List of Figures vi I. INTRODUCTION 1
' II. -- SURVEILLANCE DATA FOR 1996 AND INTERPRETATION OF RESULTS A. External Gamma Exposure Rates 5-B. Ambient Air Concentrations 11 C. Radionuclide Concentration in Water - 24
. D. Milk 49 E. Aquatic Pathways 55
- F. Sample Cross-check Program 58 G. Summary and Conclusions - 62 1
III. ENVIRONMENTAL RADIATION SURVEILLANCE PROGRAM AND SCHEDULE 75 ;
IV. ERRATA FOR 1995 REMP REPORT 93 l
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1 iii
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4 LIST OF TABLES ;
Page No. .
- II.A.1 Gamma Exposure Rates 9 i i j ll.B 1 Concentrations of Long-lived Gross Beta Particulate Activity in Air a.' First Quarter, 13-
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- b. Second Quarter, 14 '
- c. Third Quarter, 15 II.B.2 Tritium in Atmospheric Water Vapor
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- a. First Quarter, 18 .
- b. Second Quarter, 19
- c. Third Quarter, 20
- II.B.3 Tritium Released in Fort St. Vrain Effluents,1996 21 II.B.4 - Radiocesium Concentrations in Ambient Air 23
- i II.C.1 Gross Beta in Drinking Water 26 II.C.2 Tritium in Drinking Water 27 II.C.3 Radionuclide Concentrations in Bi-weekly Composites of Drinking Water. 28-32 l II.C.4 Tritium in Surface Water 35 II.C.5 Radionuclide Concentrations in Surface Water 36-42 II.C.6 Radionuclide Concentrations in Ground Water 44 ,
II.C.7 Tritium in Ground Water 45 II.C.8 Maximum Permissible Concentrations in Drinking Water 46 Y
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Page No. -
II.D.1 Radionuclide Concentrations in Milk 51-53 i l
j . II.D.2 ' Tritium in Milk 54-II.E.1 Radiocesium Concentrations in' Sediment from Location F-1 56
- II.E.2 Radiocesium Concentrations in Sediment from Location R-10 57 ;
II.F.1- EPA Cross-ch'eck Data Summary 60 '
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i- II.F.2 Intralaboratory Cross-check Results 61 -
, i II.G.1 Data Summary 67-71
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l II.G.2 Summary Table of Arithmetic Means and Standard Deviations for j' Selected Sample Types 72-73
. II.H.1 Tritium Concentrations in F-16 Well Water 74 I i'
- lll.A.1 Operational Radiological Environmental Monitoring Program 77-82
{- III.A.2 - Detection Capabilities for Environmental Sample ;
- Analysis 83 i
Ill.B.1 Sampling Site Descriptions 84-90 -
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i LIST OF FIGURES Page No.
Figure II.A.1 Gamma Exposure Rates,1978-1996 (Facility Area Only) 10 !
Figure II.B.I . Gross Beta Concentrations in Air 16 l
$ ' Figure II.C.1 Tritium Concentrations in F-16 Well Water,1984-1996 47
- l Figure II.C.2 Tritium Concentrations in F-16 Well Water 48-j Figure III.B.1 Close-in Sampling Locations 91 Figure III.B.2 3 Adjacent and Reference Sampling Locations 92 4
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l j I. Introduction to Radiological Environmental Monitoring Program (REMP) Data for the Period January 1,1996 - July 11,1996.
I I During 1996, the environmental monitoring program was concerned only with the l
decommissioning phase of the Fort St. Vrain Nuclear Station. The operational phase of the reactor ~j r .
. . 5 i' ended on August 18,1989. Fuel removal operations were completed by June 10,1992. The spent i c .
! fuel is stored near by in an Independent Spent Fuel Storage Installation (ISFSI).
s The final liquid effluent release from Fort St. Vrain was completed on July 3,1996, and the REMP program terminated on July 11,1996. Ilowever, a few samples from two sample types were actually collected later in the year. The actual sample collection dates are given in the appropriate l.
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tables.
- .A complete and dWied listing of radioactivity released by all effluent routes may be found i
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in the Public Service Company of Colorado Annual Efiluent Release Report for 1996 to the U.S. [ .
Nuclear Regulatory Commission. When possible in this report, any correlation of radioactivity m l
. environmental samples with the effluent release data is discussed. These discussions are presented
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- in the appropriate sample type section and in the summary section, II.G. !
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Table IILA.2 lists the LLD values achievable by the counting systems used during 1996 on 3
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. project samples. These values are given for typical sample sizes, counting times and decay times. j i- i The LLD is, therefore, an a priori parameter to indicate the capability of the detection system used. l l The LLD values in Table Ill.A.2 were calculated as suggested in NUREG-0472. .j i
l Throughout the report, when a sample result is listed as less than a specified value, that i .
value is the calculated minimum detectable concentration (MDC). This approach is analogous to l t
that of Currie (N'UREG/CR-4007): the MDC is the same as S, , the critical signal, and the LLD is !
L' equal to Sn, the detectable signal. The MDC value applies to the actual sample size, counting time t
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and decay time applicable to that individual sample. It is calculated for each radionuclide as:
MDC = 2.33 on EYVe*
Where: c, = Standard deviation of background count rate E = Counting efficiency, e s pCi
Y = Chemical yield (if any)
V = Sample volume (or mass)
A = 0.693/ Half-life t = Decay time between sample collection and analysis This calculation method assumes that E, Y, and V are constants and makes no allowance for systematic error.
It should be noted that we have not used the notation < MDC for values less than MDC.
Rather, we report the result as less than the actual MDC value. Because the MDC is dependent upon variables such as the background count time and sample size, the value will be difTerent for each radionuclide, for each sample type, and even within sample type.
Essentially all radioactivity values measured on this project are near background levels and, more importantly, near the MDC values for each radionuclide and sample type. It has been well-documented that environmental radicactivity values exhibit great inherent variability. This is partly due to sampling and analytical variability, but most importantly due to true environmental or biological variation. As a result, the overall var.iability of the surveillance data is quite large, and it is necessary to use mean values from a rather htrge sample population size to draw any conclusions l 1
about the absolute radioactivity concentrations in any environmental pathway.
The arithmetic mean for each sample set is listed in Table II.G.2. All measured values, both positive and negative, are used in the calculations of the arithmetic mean. This is the suggested practice by Gilbert (Ilealth physics 40:377,1984) and the NRC (NUREG/CR4007).
Many sets of data were compared in this report. The statistical test used wps either a "t"-test or a paired "t"-test. If data sets are noted to be significantly different or not significantly different, I 2
the confidence for the statement is at the 95% level ((a = 0.05),(1.96a)). ,
The Total Effective Dose Equivalent (TEDE) goal for decommissioning as set by the NRC was 10 mrem / year for any member of the general public. This is the whole-body dose rate limit i
excluding background and medical radiation dose rate.
, The maximum permissible dose commitment rate set independently by the EPA (40CFR190) for any specified member of the general public from any part of the nuclear fuel cycle is 25 mrem / year.
Dose commitments can be calculated for hypothetical individuals for any mean concentrations or exposure rates noted in unrestricted areas that are significantly above control mean values.
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The following is the footnote system used in this report. -
- a. Sample lost prior to analysis,
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- c. . Instrument malfunction.
- d. Sample lost during analysis. ';
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- e. Insufficient weight or volume for analysis.
- f. Sample unavailable.
- g. Analysis in progress.
- h. Sample not collected (actual reason given).
' i. Analytical error (actual reason given). ,
N.A. Not applicable. .
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j' d II. Surveillance Data for January Through July 1996 and ; j Interpretation of Results
' A. ' External Gamma-ray Exposure Rates i
1 For' the first two quarters of 1996 and through the end of July, the exposure rate was i
. measured as in every previous period. The average measured gamma-ray exposure rates expressed -
j in mR/ day are given in Table II.A.I. The values were determined by_ CaF2:Dy (TLD-200) -
. dosimeters at each of 41 locations (see Figure Ill.B.1). Two TLD chips per package are installed at ;
each site and the mean value is reported for that site. The mean calculated total exposure is then idivided by the number of days that elapsed between pre-exposure and post exposure annealing to 4
obtain the average daily exposure rate. The TLD devices are changed quarterly at each location.
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Fading during field exposure is minimized by the post-annealing readout procedure. All TLD's are ;
i facing north to ensure consistent solar heating. ,
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- j. The TLD data indicate that the arithmetic mean measured exposure rate (plus or minus 1.96 ;
standard ' deviations) in the facility area through July of 1996 was 0.42 (0.11) mR/ day. The annual :
'mean exposure rate was 0.45 (0.13) mR/ day for the adjacent area and 0.41 (0.11) mR/ day for the !
reference area. These mean values are nearly identical and are not significantly different from each I other and not different from the mean values measured during 1995.
I The exposure rate measured at all sites is due to a combination of exposure from cosmic l rays, from natural gamma-ray emitters in the earth's crust and from ground surface deposition of fission products due to previous world-wide fallout. The variation in measured values is due to true 4 ' variation of the above sources plus the variability due to the measurement method. The purpose of ;
having two TLD rings around the site is not to measure gamma-rays generated from the facility i
- itself, but to document the presence or absence of gamma-ray emitters deposited upon the ground i '
- from the reactor effluent. Since the inception of power production by the reactor, there has been no detectable increase in the external exposure rate due to reactor releases. Fallout deposition, from i
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world-wide fallout, from the Chinese nuclear weapon tests, and from the Chernobyl accident, has been detected in the past.
The TLD system is calibrated by exposing chips to a scattered gamma-ray flux produced in
'l a cavity surrounded by uranium mill tailings. This produces a gamma-my spectrum nearly identical i to that from the natural background' measured in the site environs. The quality control program includes calibration before readout of each quarterly batch of TLD devices.
For comparison purposes, EPA 402/R (Formerly 520/5) Environmental Radiation Data lists very similar background extemal exposure rate values measured in Denver. There has always been excellent agreement with the results from this program.
- Figure II.A.1 shows the measured mean exposure rate in the Facility Area from 1978 to 1996. The steady decrease in exposure rate over the period is due to the decay and weathering of '
fission product deposition from previous atmospheric weapon tests.
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. Table II.A.1 Gamma Exposure Rates (mR/ day) 1996 Facility Area 1st Quarter 2nd Quarter 3rd Quarter * ,
F-1 0.38 0.52. 0.50 F-2 0.37 0.41 0.48 F-3 0.42 0.28 0.43 F-4 0.39 0.42 0.42 F-5 0.43 0.41 0.51 F-6 0.39 0.37 0.37 F-7 0.39 0.34 0.38 F-8 0.43 0.51 0.54 F-9 0.50 0.39 0.41 F-10 0.37 0.49 0.47 F-11 0.4) 0.43 0.51 F-12. 0.46 0.47 0.48 F-13 0.50 0.41 0.38 F-14 0.37 0.36 0.38 F-15 0.31 0.43 0.43
, F-16 0.39 0.32 0.39 F-17 0.45 0.38 0.38 F-18 0.38 0.41 b X(1.96c) 0.41(0.09) 0.41(0.12) 0.44(0.11) b- sample missing at site
- Note: 3rd uarter q TLD's posted on 7/9/96 and collected on 8/1S6 7
b Table II.A.1 (cont'd)
Adjacent Area 1st Quarter 2nd Quarter 3rd Quarter
- A-1 0.48 0.43 0.42 A-2 0.50 0.44 0.48 A-3 0.48 0.37 0.45 A 0.38 0.40 0.34 .
A-5 0.48 0.42 0.38 A-6 0.33 0.44 0.43 A-7 0.52 0.42 0.47 A-8 0.42 0.39 0.40 A-9 0.47 0.49 0.48 A-10 0.64 0.38 0.48
- A-11 0.46 0.40 0.53 A-12 0.47 0.43 0.60 A-13 0.41 b 0.46 A-14 0.41 0.41 0.59 A-15 0.34 0.31 0.43 A-16 0.53 0.42 0.44 A-17 0.46 0.42 0.56 A-20 0.46 0.37 0.63 X(1.960) 0.46(0.13) 0.41(0.07) 0.48(0.15) b- sample missing at site
- Note: 3rd uarter q TLD's posted on 7/9/96 and collected on 8/1/96 8
Table II.A.1 (cont'd)
Reference Area 1st Quarter 2nd Quarter 3rd Quarter
- R-I b 0.31 0.43 R-2 0.49 0.41 0.45 R-3 0.31 0.37 0.48 R-4 0.45 0.37 0.45 R-7 0.37 0.40 0.40 X(1.96a) 0.41(0.16) 0.37(0.08) 0.44(0.06) b - sample missing at site
- Note: 3rd uarter q TLD's posted on 7/9/96 and collected on 8/1/96 9
m as-Gamma Exposure Rates (mR/ day) [
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II.D. Ambient Air Concentrations
- 1. Gross Beta Activity The air concentrations oflong lived particulate gross beta activity measured at the facility and reference sampling sites are listed in Tables II.B.l(a,b,c) for the first two quarters, and part of the third quarter of1996.
A-19, while technically in the adjacent zone, is only a few meters from the facility boundary and logically should be considered a facility site. It has been termed a facility site since the inception of the monitoring program. The reference sites R-3, R-4, and R-11 were established on January 1,1984 and are sufficiently distant to be considered reference (control) locations. While the R-3 location is greater than the specified distance of 30 kilometers, it has been historically used as a reference site since 1984. See Table F-4 in Offsite Dose Calculation Manual (ODCM). Note that site F-7 is in the predominant wind direction toward Platteville. Platteville is the nearest community with'the highest D/Q.
The reported concentrations are listed in units of femtocuries per cubic meter of ambient air (fCi/m'), even though the measured activity is due to a combination of radionuclides, almost all of which are naturally occurring.
The annual mean gross beta concentration in air for all facility stations for all of 1996 was
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23 (13) fCi/m'. For 1995 the mean value was 22(14) ICi/m'. See Errata section for 1995 REMP Report. The mean concentration for 1996 for all reference stations was 22 (14) fCi/m'. These measured mean values were statistically identical at the 95% confidence level.
The gross beta concentrations for 1996 have been added to the plot of air concentrations observed since 1973 (Figure II.B.1). In this figure the half-yearly mean values for the facility sites are plotted with the values from the reference sites. The contribution from the Chemobyl accident is clearly evident in 1986. It can be observed that overall mean values of the facility sites are not s significantly different from the reference sites. In fact, the long-term mean values were identical.
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World-wide fallout, principally due to past Chinese atmospheric nuclear weapon tests,'is the predominant contributor above background to the measured values over the period shown.
There has never been a significant difference observed in gross beta air concentrations between facility and reference sites. Thus, it can be concluded that reactor air effluents of' e
particulate fission products or activation products'during operation or decommissioning have not been a source of dose commitment for the Fort St. Vrain environs population. J
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l Table II.B.l(a) Concentrations of Long-lived Gross Beta Particulate Activity in Air (fCi/m 3)-
l 1" Quarter 1996 Collection Facility Reference Dates F-7 F-9 F-16 A-19 R-3 R-4 R-11 01/05 h 25 (1.1)* 27(1.1) 30 (13) 27(1.4) 27(13) 24 (1.1) 01/12 h 34 (13) 34 (13) 33 (1.4) 28 (1.4) 26 (13) 30(13) 0I/20 27(2.7) 22 (1.0) 23 (1.0) 25 (1.1) 22 (1.2) 17 (1.0) 19 (1.0) 01/27 23 (1.2) 23 (1.1) 24 (1.2) 22 (1.1) 21 (1.2) 19 (1.1) 20(1.0) 02/03 40(1.4) 40(13) 40(13) 37(13) 41(1.6) 38(1.4) 40(13) 02/10 3I(13) 28(1.2) 28(1.1) 29(1.2) 23 (1.2) 23 (1.2) 28(1.2) l 02/17 24 (1.2) 23 (1.1) 25 (1.1) 25 (1.2) 19 (1.2) 16 (1.0) 19 (1.1) 02/24 14 (1.0) 15 (0.71) !4 (0.34) 14 (0.94) 15 (0.83) 12 (0.75) 12 (0.88) 03/02 29(1.2) 29 (1.5) 29(1.1) 28(1.2) 29 (1.8) 29 (1.5) 26(1.2) 03/09 30(2.5) 30(13) 30(1.2) 31 (13) 28 (13) 27(13) 25 (1.9) 03/15 20 (1.1) 20(1.1) 17 (0.92) 24 (13) 19 (1.1) 13 (0.9I) 20 (1.2) 03/23 20(1.0) 18 (0.93) 20 (0.91) 20 (1.0) 18 (1.0) 16 (0.91) 17 (0.89) ;
03/30 33 (13) 29 (1.2) 32 (1.2) 32(13) 27 (13) 30(1.2) 26(1.2)
X 26 26 26 27 24 23 24 1.96c 14 13 14 12 13 15 14 Max: 40 Y(1.96o): 26 (13) Max: 41 f(1.96o): 23(14)
Min: 14 n: 50 Min: 12 n: 39
- 1.960 (Due to counting statistics) h - sample not collected due to lack of power to air pump
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Table II.B.1(b) Concentrations of Long-lived Gross Beta Particulate Activity in Air (fCi/m 3) d 2 Quarter 19%
Collection Facility Reference Dates F-7 F-9 F-16 A-19 R-3 R-4 R-11 04/06 22 (1.1)* 20 (1.0) 20 (0.93) 21 (1.1) 22 (1.2) 16 (0.90) 17 (0.94) 04/13 19 (1.1) 18(1.0) 19 (1.0) 18 (1.1) 19 (1.1) 18(1.0) 18(1.0) 04/20 14 (1.0) 15 (1.0) 15 (0.85) 15 (1.0) 14 (1.0) 13 (0.93) 14 (0.94) 04/27 16 (1.0) 16 (1.0) 15 (0.89) 16 (1.0) 16 (1.1) 14 (0.93) 14 (1.0) 05/04 17 (1.0) 16(1.0) 17 (0.9) 18 (1.0) 18 (1.1) 16(1.0) 15(1.0) ,
05/09 24 (13) 23 (13) 20(1.1) 26(1.4) 23 (1.4) 24 (13) 24 (1.4) 05/16 24 (1.2) 21(1.0) 22 (1.0) 22 (1.1) 22 (1.2) . 21 (1.1) 20(1.0) 7 05/23 18(1.1) 16 (1.1) 18(1.0) 19 (1.1) 20(1.2) 19 (2.4) 18(1.0) 05/30 7.2 (0.71) 7 3 (0.62) 7.1 (0.64) 6.1 (0.71) 8.0 (0.78) 7.7(0.66) 7.0 (0.65) 06/06 25 (1.1) 24 (1.1) 24 (1.0) 23 (1.1) 24 (1.2) 23 (1.1) 24 (1.1) 06/13 25 (1.2) 23 (1.1) 25 (1.1) 23 (1.2) 24 (1.2) 23 (1.1) 21(1.1) 06/20 26(1.1) 26(1.1) 26(1.1) 23 (1.2) 27(13) 27 (1.2) 23 (1.1) 06/28 19 (l.0) 20 (0.90) 11 (0.80) 14 (0.85) 19 (1,1) 19 (0.94) 18 (0.90)
, X 20 19 17 19 20 19 18 1.960 10 93 14 9.8 9.4 9.9 9 7.)
Max: 26 'ii(1.96o): 19 (10) Max: 27 i'(1 %c): 19 (8 7)
Min: 6.1 n: 52 Min: 7.0 n: 39
- 1.96o (Due to counting statistics)
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Table II.B.1(c) Concentrations of Long-lived Gross Beta Particulate Activity in Air (fCi/m3 )
3 Quarter 1996 Collection Facility Reference -
Dates F-7 F-9 F-16 A-19 R R-4 R-11 07/03 28 (1.5)* 26(13) 27(1.4) 28(1.6) 29 (1.6) 55 (23) 28 (1.4) 07/11 24 (1.1) 24 (1.0) 27 (1.5) 23(1.1) 23 (1.2) 23 (1.1) 20(1.0)
X 26 25 27 26 26 39 '24-1.960 3.9 2.0 0.0 4.9 5.9 31 7.8 Max: 28 I(1.96o): 26 (3.6) Max: 55 T(1.96o): 30 (23)
Min: 23 n: 8 Min: 20 n: 6
- 1.960 (Due to counting statistics)
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-o- Facility Sampling Stations 2=4s
- - Reference Sampling Stations v=4s 16
- 2. Tritium Activity Tritium was measured during the first two quarters and through July 11,1996 of the third quarter. The samples were collected continuously by passive absorption on silica gel at all seven air sampling stations (four in the facility area and three in the reference area). The specific activity of tritium in water extracted from these weekly samples in 1996 is listed in Tables II.B.2(a,b,c).
Table II.B.2 (a-c) reveals low but detectable concentrations of tritium as tritiated water in surface air during the first two quarters of 1996. This correlates reasonably well with the efiluent release data (Table II.B.3). Note that after the start of June, no tritium was detected in surface air, as there was minimal release during that period. Dose commitment calculations are not warranted since the mean concentrations were less than statistically significant detectable values.
17
Table ILB.2(a) Tritium in Atmospheric Water Vapor (pCi/L) 1" Quarter 1996 Collection Facility Reference Dates F-7 F-9 F-16 A-19 R-3 R-4 R-11 01/05 810 (570)* < 480 < 480 < 480 < 480 < 480 .< 480 01/12 < 490 < 490 < 490 < 490 < 490 < 490 < 490 01/20 < 380 < 380 < 380 < 380 < 380 < 380 < 380 01/27 < 380 < 380 660 (450) < 380 < 380 < 380 550 (450) 02/03 < 390 < 390 < 390 < 390 < 390 < 390 580 (460) 02/10 < 400 < 400 1860 (490) < 400 < 400 - < 400 .< 400 l
02/17 < 370 < 370 < 370 < 370 < 370 < 370 440(440)
g 02/24 830 (440) 610 (440) 840 (440) < 370 < 370 < 370 460 (440) 03/02 < 370 980 (450) 710 (450) 780 (450) 1500 (460) 1100 (450) 480 (370) 03/09 790 (450) < 370 550 (450) 700 (440) 390 (440) < 370 580 (450) 03/15 < 380 < 380 640 (470) < 380 < 380 < 380 < 380 03/23 < 380 450 (460) < 390 < 390 < 390 <390 < 390 03/30 700 (440) 810 (440) < 370 < 370 390 (440) 540 (440) 700 (440)
- 1.960 (Due to counting statistics) i
Table II.B.2(b) Tritium in Atmospheric Water Vapor (pCi/L) 2"* Quarter 1996 ,
Collection Facility Reference Dates >
F-7 F-9 F-16 A-19 R-3 . R-4 R-11 04/06 < 370 < 370 460(440) < 370 630 (450) < 370 430 (440) 04/13 740(440)* 590 (440) < 370 600 (440) < 370 < 370 390 (440) 04/20 < 380 < 380 < 380 < 380 < 380 < 380 < 380 04/27 < 380 < 380 < 380 < 380 < 380 < 380 < 380 05/04 < 390 < 390 < 390 < 390 < 390 < 390 < 390 05/09 < 370 < 370 < 370 < 370 < 370 < 370 < 370 05/16 . < 400 < 400 < 400 470 (470) < 400 < 400 < 400 g 05/23 < 370 < 370 < 370 < 370 < 370 < 370 < 370 -
05/30 <400 < 400 < 400 < 400 < 400 < 400 < 400 06M6 < 370 600 (440) < 370 < 370 < 370 < 370 < 370 06/13 < 370 < 370 < 370 < 370 < 370 < 370 - < 370 06/20 < 370 < 370 < 370 < 370 < 370 < 370 < 370 06a8 < 370 < 370 < 370 < 370 < 370 < 370 < 370 1.960 (Due to counting statistics) ,
I
_ _ _ _ _ . _ . _ _ _ _ _ _.___.ms _ _ _ _ _ _- -. - . . , - . _. . . ~ . . . , , . . .. . . . . . . .. . , _ , ,
Table ILB.2(c) Tritium in Atmospheric Water Vapor (pCi/L) 3'dQuarter 1996 >
Collection Facility Reference Dates F-7 F-9 F-16 A-19 R-3 R-4 R-11 07/03 580 (600)* < 510 - < 510 <510 < 510 < 510 <510 -
07/11 <520 < 520 < 520 <520 < 520 - < 520 - <520 1.96o (Due to counting statistics) o T m t r=- -W -
w -- - s T- e '+W r 4-'sw>' edam e- e-
Table II.B.3 Tritium Released (Ci) In Fort St. Vrain Effluents,1996 MODE JAN FEB MAR APR MAY JUN JUL TOTAL Continuous 0 0 0 0 0 0 0 0 Gaseous Stack Batch Liquid 0 1.45 E-2 3.69E-3 2.35E-2 3.12E-3 5.01 E-4 8.72E-4 4.62E-2 TOTAL 0 1.45E-2 3.69E-3 2.35E-2 3.12E-3 5.0lE-4 8.72E-4 4.62E-2 l
1 21
L; t
i I
- 3. fencentrations of Gamma-rav Emittinn Radionuclides in Ambient Air i
f Table II.B'.4 lists measured ambient air concentrations of Cs-134 and Cs-137 during the first ,
two quarters, and part of the third quarter in 1996. These results are from gamma-ray spectrum j analyses of weekly air filters composited quarterly from each of the seven air sampling stations. ;
Occasional positive values can be noted. IIowever, in every case these are very close to the lom .!
limit of detection. The occasional positive values are either measurement system false positives or !
Cs-137 concentrations possibly due to resuspension of surface soil. The Cs-137 activity in surface i
t soil is due to Chemobyl or previous world-wide fallout which is bound by clay minerals on the i
surface of undisturbed soil. For the entire year, the mean of the facility stations was not different from the mean of the reference stations (see Table II.G.2).
Although only Cs-134 and Cs-137 are reported, each gamma-ray spectmm is scanned for !
evidence of peaks from other fission products and activation products. Only gamma-ray activity I
due to the naturally occurring background radionuclides was observed in the past. During the second quarter of 1986, many other fission product and activation product radionuclides were .
detected due to the Chemobyl accident. Of these only Cs-137 can still be detected, but at steadily decreasing concentrations.
i
- Due to the time period since the end of operation, there is no logic in I-131 monitoring and I it was discontinued in January 1993. It is worthy to note that I-131, due to facility effluent, was j l
, never measured in any environmental sample during the operational phase or since the reactor was j t ,
permanently shut down in August 1989.
I J
22
3 Table II.B.4 Radiocesium Concentrations in Ambient Air. (fCi/m )
1996 Radio- Facility Reference Collection nuclide
- Periods F-7 F-9 F-16 A-19 R-3 -R-4 R-11 1* Cs-134 <0.85 - <0.58 0.50 (0.68)* <0.75 < 0.80 . < 0.72 . <0.64 Quarter Cs-137 <0.80 <0.63 <0.70 1.0 (1.0) < 0.86 <0.73 <0.71 d
2 - Cs-134 <0.65 <0.45 <0.64 <0.82 < 0.61 < 0.77 <0.58 Quarter *
- g Cs-137 <0.82 0.51 (0.60) <0.66 <0.80 0.73 (0.84) <0.81 <0.57 a
1.960 (Due to counting statistics)
Note that air filters from 7G96 and 7/11/96 were counted with 2ndquarter air filters
=
. e
+-< gr y m- y *- --,- -y,m- *h- 7-m -ww-L-ee- - e 4 -w --tys-?r- wav-+- - - - e wtamm- e.ps-- y~y -c--ee-= .- ye-ww- % - . mew si
II.C. Radionuclide Concentrations in Water ,
- 1. Drinkinu Water Drinking water is sampled weekly and composited biweekly at two locations. Location R-6 is the water faucet at the Gilcrest Post Office in Gilcrest, Colorado, and R-3 is from a water hydrant located on the old CSU dairy farm in Fon Collins. The Gilcrest well is the nearest public water supply that could be affected by the facility effluents. R-3 samples are the same as the Fort Collins drinking water supply and serve as a reference location since its source is run-off surface water from the Rocky Mountains to the west. In the past water treatment systems for the two water supplies were very different, however recently Gilcrest has adopted treatment practices that more 4
closely correspond to those of Fort Collins.
Table II.C.1 shows gross beta concentrations measured in 1996 from each water supply. -
The mean for the Gilcrest site was slightly higher than the Reference site in Fon Collins. This is ,
i due to the difTerent supply sources. The city of Gilcrest blends water from two different sources .
and it does not filter the well supply water as well as Fort Collins and natural radionuclide ;
i concentrations due to the suspended solids are responsible for the slightly highe. measured i
concentrations. As can be observed in Table II.G.2, however, the mean for the entire year for the ,
Gilcrest site was again lower than that observed prior to 1993. This decrease was due to changes in treatment practice by the town of Gilerest.
Table ll.C.2 lists measured tritium concentrations in these same two drinking water sources.
Note that an elevated concentration was observed in the Gilcrest supply in the composite sample collected January 27 and February 3,1996. No explanation for this result is known. There is however, no significant difference in the yearly mean tritium concentrations in the two drinking water supplies. The EPA limit for community drinking water systems is 20,000 pCi/L for tritium.
The two drinking water supplies were also analyzed biweekly for fission product and 24
l I
l l
, activation product concentrations. A three liter aliquot of the original sample was counted directly . )
- ' for the other gamma-ray emitters. Inspection of Table II.C.3 reveals occasional positive values of ' ]
s radionuclide concentration, but with the exception of Cs-137, these are interpreted to be random i variations about the detection limit. The'Cs-137 is the residue from the 1986 Chemobyl accident 1 i fallout as well as from past world-wide fallout from nuclear weapons testing.
a i
o i.
I b
I i
).
j- %
1 i
i s
j j
5 I
i 4
)
4 3
i i
l
)
4 4
1 25 1
Table II.C.1(a) Gross Beta in Drinking Water (pCi/L) 1st, 2nd, and 3rd Quarters 1996 Collection Gilcrest Ft. Collins Dates R-6 R-3 12/29 0I/05 1.9 (2.3)* 0.78 (0.58) 01/12 01/20 2.5 (2.3) 1.1 (0.60) 01/27 02/03 2.1 (2.3) 0.70 (0.58) 02/10 02/17 2.4 (2.3) 0.77 (0.57) 02/24 03/02 2.7 (2.3) i' O.88 (0.58) 03/09 03/I5 1.5 (2.2) 0 69 (0.57) 03/23 03/30 1.9 (2.3) 0.89 (0.58) 04/06 04/I3 0.40(2.2) 0.65 (0.56) 04/20 04/27 0.83 (2.2) 0.97 (0.58) 05/04 05/09 1.9 (2.3) 0.75 (0.58) 05/16 05/23 1.5 (2.2) 0.38 (0.56) u 05/30 06/06 0.35(2.2) 0.65 (0.57) 06/13 06/20 0.75 (2.2) 0.30 (0.56) 06/28 07/03 1.1 (2.2) 0.75 (0.57) l.96o (Due to Counting Statistics) l l
l 26 l l
Table II.C.2(a) Tritium in Drinking Water (pCi/L) ist, 2nd, and 3rd Quarters 1996 Collection Gilcrest Ft. Collins Dates R-6 R-3 12/29 01/05 < 460 < 460 01/12 Olf2'u < 390 < 390 01/27 02/03 1700 (510)* < 420 02/10 02/17 < 400 < 400 02/24 03/02 < 400 < 400 03/09 03/I5 < 390 610 (460) 03/23 03/30 < 400 < 400 04/06 04/I3 380 (450) 420 (450) :
04/20 04/27 < 390 < 390 05/04 05/09 < 400 < 500 05/16 05/23 < 390 < 390 05/30 06/06 < 400 < 400 06/13 06/20 < 380 < 380 06/28 07/03 < 500 < 500 1.96a (Dae to counting statistics) i i
27
=
M Table ILC3 Radionuclide Concentrations in Bi-weekly Composites of Drinking Water. (pCi/L)
Collection for two weeks ending fortwo weeks ending for twu weeks ending Date 01/05/96 01/2036 02/03 S 6 Radionuclide Gilcrest Ft. Collms Gilcrest Ft. Collins - Gilcrest Ft. Collins R-6 R-3 R-6 R-3 R-6 . R-3 Cs-134 < l.4 < 1.4 < 13 <0.96 < l.2 < l .4 - '
Cs-137- 4.4 (2.1)* 5.0 (2.1) 2.5 (2.0) 4.1 (1.4) 1.6 (1.8) 2.4 (2.0)
Zr-95 < 3.0 <3.6 < 3.0 <2.2 < 2.7 <3.2:
Nb-95 2.5 (2.0) <l7 2.0 (2.0) 1.2(13) < l.2 2.4 (1.8)
Co-58 < l.5 <13 < l.5 < 0.88 < 1.1 <13 Mn-54 2.0 (1.7) < l.4 < l.4 < 0.97 < l.2 <13 Zn-65 < 4.9 < 4.6 <3.9 < 2.8 <40 <43 kJ
~
Fe-59 < 4.1 4.7 (5.0) < 4.4 < 3.0 < 3.0 < 3.6 Co-60 <13 < l.4 < l.2 <0.91 < l.1 - < 13 Ba-140 <53 < 2.4 11(8.8) < l.6 <2.0 <3.5 La-140 < 6.1 < 2.7 12 (10.0) < l.8 <23 < 4.1
- 1.960 (Due to counting statistics) 5
- u. _ __. . - _ _ _---.._m.-.m_wmm._. ____.-______- m.
6 - __m
- - - - - -m-- w < - - + - - T y % 7 W'"
Table II.C.3 Radionuclide Concentrations in Bi-weekly Composites of Drinking Water. (pCi/L)
Collection for two weeks ending for two weeks ending for twu weeks ending
_ Date 02/17/96 03A)2/96 ' 03/15/96 Radionuclide Gilcrest Ft. Collins Gilcrest Ft. Collins Gilcrest ' Ft. Collins R-6 R-3 R-6 R-3 R-6 R-3 Cs-134 <13 <l.2 < l.2 < 0.98 < l.2 <l.2 Cs-137 4.1 (2.0)* 3.9 (1.7) 3.6 (l.7) 3.0 (1.5) 3.6 (1.8) - ~ 3.2 (1.8) e Zr-95 <2.8 < 2.5 < 2.5 < 2.1 < 2.7 <2.6~
Nb-95 2.5 (1.8) <13~ 2.3 (1.6) 2.5(13) <13 1.2 (1.5) ~
Co-58 < l.2 < l.0 < l.1 < 0.9 <13 <l.1 Mn-54 <l.4 1.4 (1.4) <12 < 0.97 < l.2 i .4 (1.4)
Zn-65 < 4.0 <3.6 < 3.8 < 2.9 ' <3.2 < 3.1 E
Fe-59 <3.8 <3.2 < 3.2 3.5 (3.2) <3.8 < 2.8 CM0 < l.2 < l.1 < l.0 <0.93 < l.2 <l.1 Ba-140 < 4.0 3.5 (4.0) 3.4 (3.8) <l.6 < 4.5 < l.9 12-140 < 4.7 4.0 (4.6) 3.9 (4.4) < l.8 < 5.2 <2.1
- 1.96o (Due to counting statistics)
_,--- - _ . - - - - - -
- _mu -a -- - --~ c .- - + , -- _ vc - . -,w _ w we v w -m- m e--,o.-v
Table ILC.3 Radionuclide Concentrations in Bi-weekly Composites of Drinking Water. (pCi/L)
Collection for two weeks ending for two weeks ending for two wreks ending Date 03/30 S 6 04/13/96 04/27S 6 Radionuclide Gilcrest Ft. Collins Gilcrest Ft. Collins Gilcrest - Ft. Collins '
R-6 R-3 R-6 R-3 R-6 R-3 i
Cs-134 < l.2 <13 < l.4 <l.2 0.93 (1.1) .< l.1 Cs-137 33 (1.7)* 2.8 (1.8) 23(2.0) 1.9 (1.8) 2.9(13) 2.6 (1.7)
Zr-95 < 2.7 < 2.8 < 3.2 < 2.8 < 2.0 < 2.4 Nb-95 < l.1 < l.1 13 (1.6) < l.2 < 0.86 . <l.1 Co-58 < 1.1 < l.2 < l.2 <l.1 < 0.91 < l.0 Mn-54 <l.1 < l.2 < 13 < l.2 < 0.94 1.2(13)
Zn-65 <3.1 <3.4 <3.9 <3.4 <2.4. <2.9 8 i Fe-59 < 2.8 < 3.1 <33 < 3.0 <2.5 <2.7' Co-60 < l.2 1.1 (1.4) <13 < l.1 < 0.86 <l.0 -
Ba-140 43 (33) < 2.0 < 3.7 <3.1 <2.6 < l.8 La-140 5.0 (3.8 <2.2 < 4.2 < 3.5 <3.0 .< 2.1 j
- 1.960 (Due to counting statistics) l i
l l
- M-^^ Y '" "' '
i Table II.C.3 Radionuclide Concentrations in Bi-weekly Composites of Drinking Water. (pCi/L)
Collection for two weeks ending fortwo weeks ending fortwo weeks ending Date 05/09/96 05/23!96 06/06S6
- Radionuclide Gilcrest Ft. Collins Gilcrest Ft. Collins Gilcrest Ft. Collins R-6 R-3 R-6 R-3 R-6 R-3 Cs-134 <13 <0.92 < l.0 < l.2 < l.2 < 0.87 Cs-137 2.0 (1.8)* 2.6 (1.4) 1.4 (1.5) 2.0 (1.8) 2.5 (1.9) - 2.5(13)
Zr-95 < 2.8 < l.9 < 2.6 < 2.9 < 3.1 < 2.1 Nb-95 <13 < 0.91 < 0.93 < l.1 < l.2 < 0.85 sa Co-58 < l.1 < 0.85 < 1.1 < l.1 < l.1 < 0.81
- Mn-54 <l.2 < 0.9 < l.0 <1.2 < l.2 0.87(1.0)
Zn-65 < 3.7 < 2.6 < 2.7 < 3.1 <3.6 <23 2 .
Fe-59 < 2.9 <23 4.4 (3.8) <3.5 <3.5 < 2.5 Co-60 < l.1 < 0.85 < 0.95 13 (1.4) < l.2 <0.81 Ba-140 <2.7 < I.5 < l.7 < 4.5 < 2.0 < 2.8 La-140 <3.1 < 1.7 < l.9 < 5.2 <23 <3.2 l
- 1.960 (Due to counting statistics) i i
b
_-_____m.m=___.____._______._____ _ _ _ _ _ _ . _ _ _ _ _ . _ _ _ _ _ . _ _ _ _ . _ _ __ _ _ m_.- - - , . - ...-,,,_ __- -_m m-m__. -
Table II.C.3 Radionuclide Concentrations in Bi-weekly Composites of Drinking Water. (pCi/L)
Collection - for two weeks ending for the week ending Date 06/20/96 - 07/03/96 R~ a dionuclide Gilcrest Ft. Collins Gilcrest Ft. Collins R-6 R-3 R-6 R-3 Cs-134 < l.2 < 0.87 < 0.67 < 0.96 Cs-137 2.5 (1.7) 2.7 (13)* 1.4 (1.0) 3.8 (1.5)
' Zr-95 <6.9 < l.9 < 4.1 <5.9 Nb-95 < 2.9 < 0.85 ' 2.9 (2.0) < 0.92 Co-58 < 1.0 < 0.79 < l.6 < 2.2 Mn-54 < l.1 < 0.88 <0.81 1.9 (1.5)
Zn-65 <3.4 <23 < I.7 < 2.4 U
Fe-59 12 (14) <2.5 < 6.9 < 10 Co-60 < l.1 < 0.82 < 0.67 1.1(12)
Ba-140 < 320 < 7.5 < 190 <l.7 L a-140 < 370 < 8.7 < 220 <l.9
- 1.96o (Due to counting statistics)
L e
e
, , . . _ e. .
-p - , . - . , - - -,ee . , -- s-... e - #-_, .* r=
- 2. Surface Water Surface water is collected from five sites. Since the facility liquid effluent can be directed to either the St. Vrain Creek or the South Platte River, there are upstream and downstream sampling locations on both river courses.
Table II.C.4 shows tritium concentrations measured during 1996 at the four surface water sites and the effluent route site. There were no detectable tritium concentrations at any of the sites including A-25, which is the principal water effluent route.
Table II.C.5 shows measurements of fission product and activation product concentrations in surface water samples collected monthly. There were occasional positive values, but the mean of the downstream sites was not significantly different from the mean of the upstream sites during 1996 for any of the gamma-ray emitting radionuclides measured. This has been the case since the i
inception of reactor operations at the Fort St. Vrain site. The occasional positive values are either fallcut Cs-137, which can be expected, or values close to the uncertainty limits and assumed to be false positives. Using a 95% confidence interval, 5% of the values are expected to be false positives.
In addition to the monthly sampling of the South Platte River and St. Vrain Creek, a continuous water sampler collects an aliquot of the effluent stream from the Farm Pond (A-25), at a preset frequency. The sample is dumped after each aliquot into a 5 gallon collection jug. To prevent overflow of the jug in the one week sampling period, the aliquot value and/or the sampling .
frequency is adjusted. The weekly composites are then combined and analyzed monthly. The results of these samples are shown in Tables II.C.4 and II.C.5. No elevated tritium concentrations were detected at the upstream and downstream locations through July of 1996.
Mean values of the other radionuclides were less than MDC with the exception of Cs-137.
The Cs-137 mean in downstream water was not statistically higher than upstream and therefore the 33
activity is concluded to be due to worldwide fallout. To ensure that adequate time has occurred i
~
- since the last effluent release from the facility, a final surface water sample at R-10, the downstream
~ site, was collected on September 13,1996. The analytical results of the sample are shown in Tables II.C.4 and II.C.S. ;
1 I
,i I
1 7
T I
i a
a l'
4 1
4 i
4 34 a
t
Table II.C.4 Tritium in Surface Water (pCi/L)
Collected Downstream Upstream Effluent Date St. Vrain S. Platte St. Vrain S. Platte Goosequill' F-20 R-10 A-21 F-19 A-25 01/12 < 400 < 400 < 400 < 400 < 460 02/10 < 380 < 380 < 380 < 380 < 420 03/09 < 380 < 380 < 380 < 380 < 380 04/13 < 370 < 370 < 370 < 370 < 380 05/09 < 370 < 370 < 370 < 370 <390 06/13 < 370 < 370 < 370 < 370 470 (380)*
09/13 h < 380 h h h' 1.960 (Due to counting statistics) h - sample not collected (only an R-10 surface water sample was collected on 9/10/96)
Table II.C.5 Radionuclide Concentrations In Surface Water (pCi/L)
Collection Date: January 12.1996" Downstream Sites Upstream Sites Efiluent Radionuclide St. Vrain S. Platte St. Vrain S. Platte Goosequill F-20 R-10 A-21 F-19 A-25 Cs-134 < l.4 < 0.99 <l.I < l.2 < l.2 Cs-137 4.8 (2.1)* 3.4 (1.5) 3.8 (1.7) 3.8 (1.8) 33(1.7)
Zr-95 < 3.7 <22 < 2.4 <33 <2.5 Nb-95 2.9 (2.0) ' 9 (13)
<13 < 1.5 <l.4 Co-58 < l.6 <0.89 < l.0 <13 <l.1 Mn-54 1.5 (l.7) <l.0 1.2 (1.4) < 13 2.2 (1.6)
Zn-65 <43 <2.9 < 3.2 < 3.7 <3.4 Fe-59 63 (5.4) <2.9 5.2 (4.4) < 3.8 5.0 (4.7)
Co-60 <13 < 0.89 < l.0 < l.1 <l.1 Ba-140 <23 < l.6 < l.8 <4.9 < 2.0 La-140 < 2.7 < l.9 < 2.1 <5.7 <23 1.96o (Due to counting statistics)
! ** A-25 collected January 15,1996 i
1 I
. . . . . - . .- - - . ... . . . - . - . . . - , . . . . ~ . .. . .- .
-i
, Table II.C.5 Radionuclide Concentrations In Surface Water (pCi/L) .
Collection Date: February 10,1996** '
Downstream Sites Upstream Sites - Effluent Radionuclide St. Vrain S. Platte St. Vrain S. Platte Goosequill F-20 R-10 A-21 .F-19 A-25 Cs-134 < 13 < l.2 <13 <13 < l .1.
Cs-137 5.9 (1.9)* 2.7 (1.9) 3.2 (1.9) 2.6 (1.9) $.5 (1.6)
Zr-95 ' <3.0 < 2.7 < 2.9 < 2.7 < 2.4 Nb.95 <l.5 1.4 (1.6) 3.0(13) 1.5 (1.6) <l.3 Co-58 < l.2 <12 <13 < l.2 < l.2 Mn-54 <13 <13 <13 <13 --<l.1 O Zn-65 < 4.0 <3.9 <4.2 <3.8 <3.7 i
Fe-59 <3.4 <3.4 <3.6 <3.5 <3.2 CW < l.2 < l.2 < l.2 <13 < l.0 Ba-140 < 3.8 < 2.0 4.0 (4.8) < 2.1 <4.0 -
La-140 <43 <23 4.6 (5.5) < 2.4 <4.6
- 1.96o (Due to counting statistics)
" A-25 collected February 14,1996 t
m s______._.___._______-_______m _ _ _ _ _ . --w-e. ---e---- - . - m t- --m_ es +-*,_._ r . _.--m- --e-e. ,,..y., , , - , . , , , , ,,e,.e.,e,. , ,+m... -.,-vs,p,-
w.e,., ,- .*,.,,,yy, ,,. ., ,, , , ., .,. . . , ~ . .u ..n_
Table II.C.5 Radionuclide Concentrations In Surface Water (pCi/L)
Collection Date: March 9,1996~
Downstream Sites Upstream Sites Effluent.
Radionuclide -
St. Vrain S. Platte St. Vr. tin S. Platte Goosequill F-20 R-10 A-21 F A-25
- Cs-134 <13 <l.2 <13 < l.1 <13 Cs-137 3.2 (1.8)* 2.5 (1.8) 2.9 (2.0) 2.2 (1.7) 3.8 (2.0)
Zr-95 <2.6 3.9 (3.5) <33 43(3.3) < 3.6 Nb-95 23 (1.5) < l.2 3.0 (1.7) < l.1 <l.5 Co-58 <13 <l.2 < l.2 < l.2 <I.4 Mn-54 < l.2 <l.2 < l.4 < l.1 <13 M Zn-65 <3.2 <3.0 < 3.8 <2.9 <33 Fe-59 <3.0 < 3.2 <3.9 < 2.8 <4.2 Co-60 < l.1 < l.2 <13 < l.1 <13 Ba-140 <2.0 < 1.9 < 5.1 <3.4 ' < 2.2 La-140 <23 < 2.2 < 5.8 < 3.9 - < 2.5 l
- 1.960 (Due to counting statistics)
" A-25 collected March 15,1996 -
m -
Table II.C.5 Radionuclide Concentrations In Surface Water (pCi/L) -
Collection Date: April 13,1996~
Downstream Sites Upstream Sites Efiluent Radionuclide i
St. Vrain S. Platte St Vrain S. Platte Goosequill +
F-20 R-10 A-21 F-19 iA-25 Cs-134. <0.92 < l.2 < l .2 - < l .1 . <l3 Cs-137 3.5 (1.4)* 3.0 (1.8) ' < l.5 2.9 (1.6) 3.7 (1.9) .
Zr-95 <2.1 <2.6 5.5 (3.6) <2.7 .<2.9 Nb-95 <0.88 <12 <I.2 < l .1 - <l.2 ;
Co-58 1.2 (1.2) < l.2 <l.1 < l.0 <l.4- !
Mn-54 < 0.94 <l.2 < l.2 < l.1 1.4 (1.6) ,
E Zn-65 < 2.4 <2.9 <3.2 <2.9 <3.0' i
Fe-59 <23 <3.5 < 2.9 < 2.7 < 3.9 Co-60 < 0.87 < l.1 < l .1 - < l.0 < l .2 . -
Ba-140 < 3.1 <3.6 < l.9 <3.6 <2.0-La-140 < 3.6 <4.1 < 2.2 <4.1 <23 !
- 1.96o (Due to counting statistics)
" A-25 collected April 15,1996 i
r v
t
. . . . _ _ _ _ . . .- . _ _ _ _ _ _ . _ . . _ - . . . . - - - - . - - . . - . . . . . . - . - . - . - . . . . . . - . . . . ~ . - .
Table II.C.5 Radionuclide Concentrations In Surface Water (pCi/L)
Collection Date: May 09,1996~
Downstream Sites Upstream Sites Efiluent Radionuclide St. Vrain S. Platte St. Vrain S. Platte Goosequill F-20 R-10 A-21 F-19 A-25 Cs-134 < 0.88 < l.1 2.0 (1.5)* < l.0 < l.1 Cs-137 33 (13) 2.2 (1.6) < l.5 2.2 (1.5) 2.4 (1.6)
Zr-95 < l.9 < 2.9 < 2.7 < 2.6 <3.1 hb95 < 0.83 1.7(13) < l.1 < 0.93 < l.0 Co-58 <0.79 < 1.2 < l.1 <0.91 <13 Mn-54 < 0.86 1.6(13) <l.2 < 0.97 < l.1 8 Zn-65 <2.2 < 2.6 <3.4 < 2.6 < 2.8 Fe-59 < 2.9 < 2.5 < 4.2 <23 5.6 (4.9)
Co-60 < 0.8 <0.97 < l.2 < 0.91 < 1.0 Ba-140 < l.4 < l.7 < l.9 < l.6 < 8.7 La-140 < l.6 < l.9 < 2.2 < l.8 < 10.0
- 1.96o (Due to counting statistics)
- A-25 collected May 15,1996
- i. j Table II.C.5 Radionudide Concentrations In Surface Water (pCi/L)
Collection Date: June 13,1996~
Downstream Sites l Upstream Sites -
Efiluent Radionuclide !
St. Vrain S. Platte St. Vrain S. Platte Goosequill F-20 R-10 A-21 F-19 A-25 Cs-134 <2.0 <2.4 < l.2 <1.2 < 0.82 Cs-137 <2 5 <3.1 2.2 (1.8)* 2.5 (1.3) 1.7 (1.2)
Zr-95 <43 <5.4 <2.6 < 2.5 <5.1 Nb-95 < 2.0 < 2.6 < 12 < l.1 < 2.2 Co.58 . 2.2 (2.5) < 2.5 < l.2 <2.0 1.5 (1.5)
Mn-54 < 2.1 < 2.2 13 (1.4) < l.2 <l.0 t Zn-65 < 5.7 < 6.6 <33 <3.1- < 2.0 Fe-59 <5.8 < 5.7 <3.4 5.6 (4.1) <9.1 Co-60 < l.8 <23 < l.1 <12 <0.79 Ba-140 <6.8 12 (9.5) - <4.1 < l.9 <13 La-140 _ < 7.8 13 (11) <4.7 <22 <l.5
- 1.96o (Due to counting statistics)
- A-25 collected June 15,1996
.p w yg - .w-- , - wy 4 -.^r-tw- gnm 5 + h.- e -ase v w -
. a 1-
~
Table II.C.5 Radionuclide Concentrations In Surface Water (pCi/L);
Collection Date: September 13,1996
. Downstream Site Radionuclide S. Platte
- R-10 Cs-134 ' < l .1..
. Cs-137 1.9 (1.7)*
Zr-95 <2.5 Nb-95 1.6 (1.4)
Co-53 <l.2 Mn-54 < l.1 a
Zn-65 <3.0 Fe-59 <2.8 Co < l.1 Ba-140 < l.9 La-140 <22 .
- 1.960 (Due to counting statistics)
, .e*w-e= "17M.W '=T
- FP TT'8' IW*8 * * *
- 3. Ground Water Ground water was sampled quarterly at two locations. These are at F-16, a well on the farm immediately north and the closest to the facility down the hydrological gradient, and at R-5, a well at a personal residence in the town of Milliken, both locations are down the hydrological gradient from the facility. Tnble II.C.6 lists the measured concentrations of fission products and activation products in ground water. The Cs-137 results are not surprising due to residue of Chemobyl fallout. The other occasional results above MDC are assumed to be statistically false positive values.
Table II.C.7 shows tritium concentrations in the same well water samples. No tritium concentrations above the MDC were observed. Figure II.C.1 shows measured tritium concentrations in the F-16 well from 1984 through 1996. Figure II.C.2 shows the data from 1994 through the end of the REMp sampling period. Note that since 1993 only slightly elevated concentrations were observed. During the operational and decommissioning period, the water from F-16 was never used for drinking purposes. We initiated a weekly sampling of this site beginning early in 1991 and have continued to date. 'lle data for the weekly samples of the F-16 well for 1996 are shown in Table II.G.1 (see Summary section).
For comparison purposes we include Table II.C.8 which lists the Maximum Permissible Concentrations in drinking water from the old 10CFR20.
i 43
L.',},
Table II.C.6 Ra'dionuclide Concentrationiin Ground Water (pCi/L) l l' 2*d l Radio- Quarter Quarter ,
nuclide F-16 R-5 F-16 R-5 Cs 134 <l.6 f <l.2 <l.2 Cs 137 6.1 (2.3)* f 2.7 (1.7) 4.0 (1.8)
Zr-95 :<3.3 f <2.7 <2.6 l Nb-95 <l.8 f <l.1 <l.2 l Co <l.5 f 1.4 (1.4) 1.2 (1.4) >
Mn 54 <l.6 f <l.2 <l.2 Zn-65 <5.8 f <3.4 <3.9 .
Fe-59 <3.7 f <3.1 < 2.8 Co-60 <l.5 f <l.1 <1.1 ,
Ba-140 <3.3 f <2.7 < 2.6 ;
La-140 < 3.8 .f <3.1 <2.9
- 1.96o (Due to counting statistics) f- Sample unavailable (Well pump was frozen all quarter) I i
I a s i
I .
p .
l 5
q.
I i
4 4
. 44
~
l
,-. / + .
x -
.=
NL Table ILC.7 Tritium in Ground Water (pCi/L) .' .v O
First Quaiter 1996 "'
Second Quarter leM "
Collected: ', Collected:'
Fetxuary 24 - May 9 F-16 R-5 F-16 ' R- 5 '
s
< 400 f - < 390 - < 390 -
c.:
f- Sample Unavailable (Vcell pump frozen all quarter)
N
.+
6 f
v S
+'
- M..
_s , , ,w- _ . . . ,, -+.. , - - . - - , - . - - . -
. . - . ..---.L,.,.
m = , - - + ~ - . - - - - - - = . <~ + < = - . - - - - - - - - - - - -
1 Table II.C.8 Maximum Permissible Concentrations in Drinking Water.
(10CFR20, Appendix B Table 11, previous edition)
Radionuclide Concentration (pCi/L)
H-3 3 x 10' l-131 3 x 10 2 Cs 134 9 x 10' Cs-137 2 x 104 Zr-95 6 x 104 Nb-95 1 x 10' Co-58 1 x 10' Mn-54 1 x 10' Zn-65 1 x 10' Fe-59 6 x 10*
Co-60 5 x 10*
Ba-140 3 x 104 La 140 2 x 104 s
46
w.
Tritium Concentration in F-16 Well Water "i 1984-1996 .
10000 t
n e 2
o i l i &
i D ,O.
8 1000 ;_ . .
i M
- l i; i !
'l i
i /\
f f t I
c I
\ / il \ /\
1 \1 / l If \/ \
8 R 1 V ,W L -i 1
- A j\ ; y j -
-.....w, o d W WV 100 . , , , . .. . .. . . . .... ,.,.., . , , , , . ... . . . .. . , , , . , . .
84 85 86 87 88 89 90 91 92 93 94 95 96 Year s'T -__ --m - _ _ m__
w.
on C
Tritium Concentrations at F-16 Well Water i O
b ,
~
1994 1995 1996
'10000 3
A 5c.
C O '
'j 1000 t ,
t C
e c .
o wa : . = : +; .
O _. m d 100 2 3 3 : S h {t S -2 2 h s e i a: s 'S e -
Date Collected
b II.D. Milk '
. l 4
The dairy food chain is the critical pathway for potential radiation dose commitment around -
any nuclear facility. This is true for both chronic and acute releases. The critical individual would be an infant consuming milk produced from cows grazing local pastures. Milk is the critical
! pathway for potential dose commitment to humans from environmental contamination of H-3 and Cs-137. For this reason milk is sampled extensively to document the presence or absence'of radioactivity due to the decommissioning operation.
There are no dairies (or personal milk cows) in the facility area which is within a 1.6 km
! radius from the facility. The five dairies in the adjacent area,1.6-8 km radius, were selected as they are located in the highest X/Q areas. The description of these locations can be found in Table F-4 s ,
of the ODCM and Figure III.B.2. The single reference location dairy, R-8, is 22.5 km Northwest of i the facility in the least predominant wind direction. Herd management practices are similar at all
{ dairy locations. The cows in the milking herd are never on pasture but are under dry-lot management which is typical of the Western U.S.
Table II.D.1 lists the concentrations of all gamma-emitting radionuclides that are measured
]
l in milk samples.
l Natural-potassium, as measured by K-40, is extremely constant in milk. The mean 4 l literature value for cow milk is 1.5 g/L. K concentrations are homeostatically controlled and '
independent of K intake. K-natural is measured in n!! milk samples as a quality control measure for 1
the other radionuclides determined in the same sample by gamma-ray spectrometry. l Table II.D.2 lists measured tritium concentrations in milk. Elevated tritium concentrations ;
a in milk due to facility effluents were not observed during the operational or defueling phase, or the decommissioning phase. The mean of the 5 adjacent sites was not statistically greater than the '
reference site. This implies that any tritium from facility effluent is not contributing radiation dose 49
- to humans via the milk pathway. Tritium concentrations in milk should respond rapidly to changes !
in tritium concentrations of the forage water intake or drinking water intakt .o the cow. This is due to the short biological half-life for water in the cow (about three days for the lactating cow). As noted in previous reports, the reported tritium concentration in milk is the tritium in water extracted - :
from the milk. Contamination of milk samples by any radionuclide due to facility effluents has .
never been observed during the operational, defueling or decommissioning phases of the Fort St.
Vrain Station.
t I
f 50
Table II.D.1 Radionuclide Concentrations in Milk (pCi/L)
Location A-6 A-18 A-23 A-26 A-28 R-8 Collection 01/12 01/12 01/12 01/12 01/12 01/12 Date Cs-134 <l.5 <l.6 < l.6 < l.5 < 13 <l.2 Cs-137 5.5 (2.6)* 6.0 (3.0) 3.9 (2.8) 43(2.6) 53 (2.4) 2.7 (2.1)
Ba-140 <3.1 7.7 (5.0) <23 <2.2 < l.9 < 2.7 La-I40 < 3.6 8.8 (5.8) < 2.6 <2.5 <2.2 < 3.1 Collection 02/10 02/10 02/10 02/10 02/10 02/10 Date Cs-134 < I.7 < l.4 <I.5 < l.4 < l.2 13 (1.4)
Cs-137 3.5 (2.9) < 2.2 4.1 (2.7) 3.6 (2.6) 6.2 (2.0) 5.1 (2.1)
$ Ba-140 < 2.4 <2.2 <2.2 < 2.9 <l.7 <l.7 La-140 < 2.8 < 2.5 < 2.6 <33 < I.9 < 2.0
- 1.960 (Due to counting statistics)
Table II.D.1 Radionuclide Concentrations in Milk (pCi/L) :
Location A-6 A-18 A-23 A-26 A-28 R-8 ,
Collection 03/09 03/09 03/09 03M9 03M9 03/09 Date ,
Cs-134 < I.6 <l.4 < l.1 <l.4 < l.4 <13 Cs-137 <2.4 4.6 (2.5)* 4.9 (2.0) 5.1 (2.4) 3.5 (2.6) 43(2.4)
Ba-140 < 2.4 < 2.7 <2.2 < 2.9 <33 <2.0
^
La-140 < 2.7 < 3.1 < 2.5 <3.4 < 3.8 '<23 Collection 64/13 04/13 04/13 04/13 04/13 04/13 Date i
Cs-134 < l.5 < l.4 < l.6 b < l.5 < l.1 <
Cs-137 43(2.6) 4.5 (2.5) b 5.1 (2.7) <23 4.9 (2.0)
Pi Ba-140 < 2.6 <33 < 3.8 b
<23 < l .6 La-140 I
< 3.0 <3.8 < 4.4 b < 2.6 < l.9 Collection 05/09 05/09 05/09 05M9 05/09 05/09 Date Cs-134 < l.1 < l.4 < l.4 < l.1 < l.4 < l.4 Cs-137 4.6 (2.0) 4.9 (2.5) 2.1 (2.5) 4.0 (2.0) 3.4 (2.6) 2.7 (2.5)
Ba-140 <l.6 <3.8 <2.0 <l.6 <2.0 < 2.1 La-140 < l.9 < 4.4 < 2.4 < l.8 <23 < 2.4
- 1.960 (Due to counting statistics) b - sample unavailable at site
- _. . , , . , . - . , , , p , m- - v- p1g sei 4v , ., - -
~
Table II.D.1 Radionuclide Concentrations in Milk (pCi/L)
Location A-6 A-18 A-23 A-26 A-28 R-8 Collection 05/23 05/23 05/23 05/23 05/23 0 5/23 Date Cs-134 b < l.5 <l.5 <13 < l.5 < l.1 Cs-l37 b < 2.1 5.4 (2.6)* 4.4 (2.4) 4.5 (2.5) 43(1.9)
Ba-140 b < 2.1 < 6.0 < 5.6 <2.1 <3.4 La-140 b < 2.4 < 6.9 < 6.5 <2.5 <3.9 Collection 06/13 06/13 06/13 06/13 06/13 06/13 Date Cs-134 < l.5 < l.4 < l.0 <2.5 < l.6 <13 Cs 137 33(2.6) 5.4 (2.5) 5.6 (l.9) < 3.6 3.6 (2.7) <2.0
$ Ba-140 < 2.1 < 2.8 < 23 < 6.2 < 4.1 < l.9 La-140 <2.4 <33 < 2.6 < 7.1 < 4.7 <i.2 Collection 06/28 06/28 06/28 06/28 06/28 06/28 Date Cs-134 < l.1 < 0.93 < l.3 < l.4 < l.2 < l.1 Cs-137 ' 3.4 (1.8) 5.0 (l.7) 4.5 (2.3) 3.9 (2.4) 3.6(23) 3.6 (1.8)
Ba-140 < l.5 < l.4 < l.9 < 2.0 < 340 < l.4 La-140 < l.7 < l.7 < 2.2 <23 < 390 < l.6 l
- 1.96o (Due to counting statistics) b - sample unavailable at site
_.____m__..___.________________________m - _ _ - .
Table II.D.2 Tritium in Milk (pCi/L)
Collection Adjacent Reference Dates A-6 A-18 A-23 A-26 A-28 R-8 01/12 < 510 < 510 < 510 < 510 <510 < 510 02/10 < 430 < 430 < 430 < 430 < 430 480(510)'
03/09 < 370 520(440) < 370 530(440) < 370 < 370 04/13 < 380 < 380 < 380 b 420 (450) < 380 0109 620 (460) < 380 < 380 < 380 < 380 < 380 05/23 b 460(440) 390(440) 490(440) < 370 < 370 06/13 450(440) < 370 < 370 < 370 < 370 < 370 g 06/28 < 390 < 390 < 390 < 390 < 390 < 390
- 1.96a Due to counting statistics b - sample unavailable at site l
II.E. Aquatic Pathways (Sediment) -
Table ll.E.1 shows the measured concentrations for the first half of 1996 of both Cs-137 and Cs-134 in surface sediment collected at F-1, located at the intersection of the Goosequill and Jay Thomas ditches. There was measurable activity of Cs-137 above ambient background levels and certainly due to the decommissioning effluent. The concentrations observed in 1996 were less than observed in 1995 which was less than observed in 1994. The mean values for F-1 in 1994,1995, and 1996 were 160 (250),110 (140), and 55 (80) pCi/kg respectively.
Table II.E.2 shows the radiocesium concentration in sediment at locations R-10, the downstream location. At this site, no Cs-134 or Cs-137 activity concentrations above MDC were detected.
Therefore, it can be concluded that Cs-137 due to decommissioning work did not reach this downstream location.
A final sediment sample at F-1 and R-10 was also collected on September 13,1996. These results are shown in Table II.E.1 and II.E.2.
Note that fish samples were not collected during 1996.
55
Table II.E.1 Radiocesium Concentrations in Sediment from Location F-1 t
Radionuclide Concentration (pCi/kg)
Collection Date: January 12,1996.
Cs-134 < 22 s Cs137 48 (29)*
Collection Date: February 10,1996 Cs-134 < 22 Cs 137 < 24 Collection Date: March 9,1996 '
Cs-134 . < 26 Cs 137 129(36)
Collection Date: April 13,1996 Cs-134 < 24 Cs-137 44 (34)
Collection Date: May 9,1996 -
Cs 134 , < 21 Cs-137 < 24 Collection Date: June 13,1996 Cs-134 < 24 Cs 137 59 (33)
Collection Date: September 13,1996 Cs 134 < 24 Cs-137 44 (31) 1.96o Due to Counting Statistics a
56
f
. Table II.E.2 Radiocesium Concentrations in Sediment from Location R-10 l
Radionuclide Concentration (pCi/kg) >
Collection Date: May 9,1996 Cs-134 < 25 Cs-137 < 26 Radionuclide - Concentration (pCi/kg)
Collection Date: September 13,1996 Cs-134 <5.7
' Cs-137 < 12 .
- 1.96o Due to Counting Statistics i
f k
I 57
II.F. Sample Cross-check Program .
To assure both the accuracy and precision of the environmental data obtained from the radiation surveillance program provided for the Fort St. Vrain facility, Colorado State University participates in both interlaboratory and intralaboratory quality assurance efforts. The U.S. Environmental Protection Agency (EPA) sponsored laboratory intercomparison studies program is the principal cross-check. This involves the analysis of a variety of environmental media containing various levels of radionuclides.
The media, type of analysis and frequency of analysis for the EPA program are summarized below.
Medium Analysis (radionuclide) Freauency Water H-3 Semiannually Water Gross p Annually Water Co-60, Cs-134, Cs-137 Semiannually Air particulate Cs-137, Gross p Annually Milk Cs-137 Annually For each radionuclide analysis of a particular medium, three independent measurements are performed and all results are reported to the EPA. It should be noted that during 1989, the CSU laboratory became l
certified by the EPA for drinking water analysis although due to lack of use this certification has lapsed.
Table II.F.1 gives the EPA cross-check data for 1996. The EPA uses the parameter, Estimated Laboratory Precision (ELP), calculated as one standard deviation for one determination. The normalized deviation of our mean from the known is calculated as:
ELP = CSU mean value - EPA known value o in Where: o = standard deviation of the mean of all participating laboratory results n = number of analyses by our laboratory, normally n=3
$8 P
The control limit is determined by the mean range of all participating laboratory results and three standard deviations of the range. If any result exceeds three standard deviations from the mean (waming level), the result is unacceptable. Whenever our mean value falls outside this limit, the calculations are rechecked and the sample reanalyzed if possible. During 1996 all samples except one were within the warning level. The sample exceeding the warning level has the superscript notation 1-3 in Table II.F.1. The explanation for the incorrect result is given in Table II.F.1. The remaining results are not available at the time of this writing.
As in the past, water samples were split between the CSU laboratory and the laboratory at the Colorado Depanment of Public Health and Environment (CDPHE). The data for 1996 from CDPHE was not available at the time of this writing.
Table II.F.2 shows results of an intralaboratory cross-check program. Replicate samples are independently analyzed. The repRate results are not statistically different and imply that the precision of the methods is acceptable.
During 1996 approximately 20% of all laboratory calculations that partly involve technician input were recalculated by a different technician. Only an occasional input or calculation error was detected. This result gives further credence to the laboratory results which are not solely computer ;
i calculated and listed. I Computer calculations are often recalculated by hand and those done during 1996 were all i
verified to be correct. , '
During June of 1996, one dried milk sample was split between the University of Costa Rica and our laboratory here at CSU. Our result was 87 pCi/kg (dried weight), and their results was 103 pCi/kg 4 (dry weight). The calibration of their laboratory is traceable to the IAEA/FAO. The agreement was acceptable.
59
1 l
Table II.F.1 EPA Cross-Check Data Summary,1996.
C Date Radionuclide CSU Value EPA Value 1 E.L.P.
- Normalized Deviation l from known*
- l WATER, Tritium (pCi/L)
'H 24200 22002 2200 1.73 Mar 08
'll 12000 g g g Aug 09 WATER, Beta (pCi/L)
Beta N.A. N.A. N.A. N.A.
Jan 27 WATER, Gamma (pCi/L)
Jun 07 Co-60 f f f f f f Cs-134 f f Cs-137 f f f f g g g g Nov 03 Co-60 g g g g Cs-134 g 'g g g Cs 137 WATER, Performance (pCi/L)
Beta 120.7 166.9 25.0 -3.20' Apr 16 21.1 46.0 5.0 -8.54 2 Cs-134 Cs-137 24.5 50.0 5.0 -8.78' MILK (pCi/L)
Cs-137 g g g g Sep 29 -
AIR FILTERS (pCi/ Filter)
Beta g g g g Aug 25 24.5 g g g Cs-137
- E.L.P. = Expected Laboratory Precision.
- Normalized Deviation = (CSU mean EPA knowny(oVn);if this value falls between upper & lower warning levels, the accuracy is acceptable.
g analysis in progress and/or awaiting results from EPA f sample not performed GeLi detectors not operating at time of test 1,2,3 analytical error, nitric acid concentration was incorrect 60
Table II.F.2 Intralaboratory Cross-Check Results (pCi/L).
(Replicate Analysis of Same Sample listed as A & B)
Radionuchde Drmking Water ist Quaner 2ndQuener A B , A D Cs 134 < l .2 < l .3 < l .3 < l .2 Co 131 3.6 (l.7) 4.7 (l .9) 2.0 (l .8) 1.4 (l 8) 7e95 < 2.5 < 2.7 < 2.8 - < 2.7 Nb95 2.5 (l?) < l.3 < l.3 < l .1 Co58 < l .1 < l.1 < l .1 < l .1 Mn-34 < l .2 <13 < l .2 < l.2 7# 63 < 3.8 < 3.9 < 3.7 < 3.3 Fc59 < 3.2 < 3.5 < 2.9 < 3.2 Co-60 < l .0 < l .2 < l.1 < l .0 Bo l40 3.4 (3.8) <40 < 2.7 < 2.7 la 140 . 3.9 (4.4) <46 < 3.1 < 3.2 Gross Dets 2.7 (2.3) 3.1(23) 0.24 (2.3) 1.9 (2.3) 11-3 < 400 430(460). < 390 < 390 Radionuclide Milk ist Quarter 2ndQuanet A D A D Cs 134 < l .3 < l .5 < l .4 < l .2 Cs-137 3.3 (2.7) 4.l (2.7) 2.l (2.5) 3.3 (2.1)
Da 140 < 2.2 < 2.2 < 2.0 < l .7 1 a-l40 < 2.5 < 2.6 <24 < 2.0 11-3 < 430 < 430 < 380 < 380 l.W (Due to Counting Statistics) 61
' il.G. ~ Summary and Conclusions Table II.G.1 summarizes the radiation and environmental radioactivity measurements conducted during 1996 in the environs ~ of the Fort St. Vrain facility. This is the final reporting l period for the REMP Program. The REMP Program was instituted in 1970 and has carried on until present.
The . values for each sample type in this report may be compared to pre-operational and operational periods for this facility, as well as to the values from other U.S. environmental monitoring programs (e.g., EPA 520). It must be emphasized, however, that the mean values in Table II.G.1 are only the means of the values greater than MDC, the statistically. minimum
' detectable concentration. The range also is given only for detectable measu ements. The mean and range values, therefore, are not the true means or ranges if any of the values in the sample population were less than MDC, i.e. the mean values in the rest of Table II.G.1 are overestimates of the true mean. The calculational methods and the format of Table II.G.1 is a requirement of the NRC.
Inspection of Table II.G.1 reveals that there were no individual measurements that exceeded the Reporting Level (RL) (see Table F-3 in the ODCM). The Chemobyl world-wide fallout was still observable as Cs-137 in several sample types. Decommissioning activity was observed in Goosequilt sediment samples.
For the category of gross beta concentrations in drinking water, the mean for the Gilcrest well was again significantly greater than for the reference supply located in Fort Collins. The reason for this observation is solely due to the fact that the town of Gilcrest still doesn't completely i filter its drinking water supply. The procedure was improved in the last three years but it is still not !
complete and the activity concentration is still elevated due to naturally occurring radioactive materials from soil and fertilizer contamination. The following conclusions are drawn.
j l
)
.c
- a. None of the individual fission product or activation product radionuclides measured were significantly higher in the Gilcrest drinking water.
- b.- Tritium concentrations measured at Gilcrest were not statistically greater than those in Fort Collin' s.
l
- c. The city of Gilcrest does not filter and treat its well water to the same degree as Fort Collins. This has been verified and evidenced by the fact that the gamma-ray spectra of the suspended solids from Gilcrest water samples show only elevated concentrations of the natural l radionuclides. It has been concluded in previous reports that the elevated gross beta concentrations ,
in Gilcrest water are due to elevated concentrations of the naturally occurring U-238, and Th-232 decay products.
For the category of tritium in surface water no elevated concentrations were noted at station A-25, the outlet of the Farm pond, throughout 1996. A-25 is directly in the principal effluent route y
! and elevated concentrations were noted in the past when release was significant. During 1996 elevated tritium concentrations were not observed downstream.
- Cs-137 was also observed in many environmental samples but is due to the remainder of
- Chemobyl world-wide fallout. The only exception was the elevated Cs-137 in sediment in the i
liquid efiluent pathway. These values, however, are well below NRC guideline values and have ,
- i decreased from 1994 to 1996.
! Tritium concentrations from quarterly samples at well water site F-16 were all less than the minimum detectable concentrations. Weekly sampling was initiated in 1991 to observe the
- movement more closely, but in any ca$e the well at F-16 is not used for drinking water purposes 4
j and elevated tritium concentrations have not been observed in any food chain sample. Residents at
- o the F-16 residence purchase bottled water for their primary water consumption.
Table ll.G.2 presents an additional summary of mean values for selected sample types. The l sample types and radionuclides were chosen on the basis of their importance in documenting possible radiation dose to humans. Air and surface water would be the predominant environmental transport routes and drinking water and milk would be the predominant sources of radiation dose if
. l 63 i
L t
?
lsignificant radioactivity release from FSV occurred. Table II.G.2 also allows comparison to the {
i
-_ four most recent years of monitoring. All four years were post-operational.
. l i
The arithmetic means and standard deviations in Table II.G.2 were calculated for all sample ;
results. It should be repeated that the tabular data presented in the body of this report contain only l positive calculated values abo've the minimum detectable concentration (MDC) levels. Any j calculated values less than zero or less than the minimum detectable concentration are listed as less l l
than the actual MDC for that sample analysis. The actual result in all cases, however, was used in the calculation for the arithmetic mean values for the periods in Table II.G.2. Therefore, all values, !
i negative as well as positive, were included. This procedure is now generally accepted and gives a
- ' proper estimate of the true mean value. Because of this procedure, however, the values listed in i
Table II.G.2' cannot be calculated directly from the tabular values in the repon. It must be emphasized that while it is true that no sample can contain less than zero radioactivity, due to the j random nature of radioactive decay, it is statistically possible to obtain sample count rates less than !
background and hence 'a negative result. It is equally tme that many sample types do in fact have l
b zero concentrations of cenain radionuclides. Therefore, to obtain the correct mean value from the i i ;
lL distribution of analytical results, all positive results must be averaged with all negative results. If )
4
- the negative results were omitted, the resulting arithmetic mean would be falsely biased high. )
From the values presented in Tables 11.G.1 and II.G.2 and the tabular data of th,e report, the j following observations and conclusions may be drawn:
l 1. As in every previous report, it was again apparent that for most sample types the i variability observed around the mean values was great. This variability is panly due to counting i
statistics and methodological variation, but principally due to true environmental variation (often I
termed sampling error). It must be recognized and accounted for in analyses of any set of i
!. environmental data before meaningful conclusions can be drawn:
- 2. Tritium was no longer detected in the effluent pathway throughout 1996. The
! release of tritium was indeed much less than in previous years. Since the tritium is released as tritiated water, the dilution by the surrounding hydrosphere is great and consequently the mean l'
. 64 i
1 values of downstream surface water were not statistically greater than upstyeam concentrations.
Therefore, no tritium could be expected at the downstream R-10 location because none was found.
]
1
- at the A-25 emuent. Very low tritium concentrations were observed in ground water. samples (see j Table II.G.1)... ,
n .- . .
a
- 3. The Chemobyl world-wide fallout has totally obscured what fission product debris !
has remained in the FSV environs from the October 1980 Chinese atmospheric nuclear weapon
. test. The biosphere will'contain the Chemobyl fallout, particularly Cs-137, for an equally long l i
j period. Nuclear weapon test fallout has, since the inception of the project, been noted to be_the s t, ' l predominant source term;above natural background. The Chernobyl r.eactor fire debris .was~
]
superimposed on the weapons test fallout from 1986 to present. It is the variation in fallout {
i deposition, in addition to the variation in naturally occurring radionuclides, that mandates the large I
number of environmental samples to detect any possible radioactivity due to facility emuents. A j i
-J simple comparison of pre-operational and operational values is of little value, for most sample types, because the fallout deposition was considerably greater during the pre-operational period due )
i to world-wide fallout, and has decreased due to weathering .
- 4. The prompt and sensitive detection of the Chinese weapon test fallout and the .
t Chemobyl fallout in the past and the decrease in this deposition assures that the environmental monitoring program was of adequate scope and sensitivity to detect any accidental releases from i
the FSV decommissioning; and ;
- 5. Release of decommissioning radioactive emuent was evident only in the Goosequill i i
sediment. Since this is primarily Cs-137 in sediment, its transfer to plant and animal food chains l will be negligible. .
it can be concluded from the data collected by the environmental monitoring program that l 4
m . .
the radiation dose commitments calculated for the closest human inhabitants or other parts of the l
nearby ecosystems due to past facility emuents are negligible. Natural background radiation and the dose commitment from atmospheric fallout are the only known significant sources of radiation l
I
- dose to the residents of the area.
Il! I 65 i
- - - -=,_' - _ _ _ .._ _ . - _ v .. --
f 1 t, !
- At;. the end. of the decommissioning. phase of. the facility, it is concluded 'that this
. Radiological Environmental Monitoring Program was more than adequate fo ' detect and quantify i any possible routine or accidental release of radioactivity.
i i
R' ,
I c j i
h 1
o k
E r
I l
t l
f i
i
{ s > l
. 66 i
g s
Table II.G.1 Radiological Environmental Monitoring Program Annual Summary Fort St. Vrain Station, Platteville, Colorado Med um or Type and Total Facility laations l Adjacent Locations with liighest Annual h1can Reference Number of Pathway Samples Number of hican (f) Range Locaions hiean Name Atcan Locations Mean Nonroutine (Unit of Analyses (f)1 Range Distance & Range (f)I Range Reported '
measurement) Performed Direction hicasurements Direct Radiation TLD (120) 0.37(53/54) 0.40 (53/54) A-12 CR 34 0.46(3/3) 0.36(14/15) 0 (mR/ day) (0.22-0.52) (0.20-0.64) 7.2 km Sec 12 (0.43-0.48) (0.26-0.49)
Air, Particulates Gross Beta (194)
D (I Wil2) _
F-7 CR 21 & 34 23 (26/28) 22(84/84) 0 (fti/m3) (6.1-40) 1.5 km Sec 7 (7.2-40) (7 0-55)
Gamma Spectrometry F-16 Rasell Cs-134 (14) 0.51(l!8) -
0.51(1/2) -
0 0 1.5 km Sec 1 Cs-137 (14) 0 .75(2/8) A-19 liunter's 0.98(1/2) 0.73 (1/6) 0 (0.51-0.98) Cabm 1.7 km Sec I Air, Atmospheric 730 (23/112) R-4 U.S. 66 & 820 (2/28) 610(15/84) 11-3 (1%) _
Water Vapor (450-1860) U.S.287 (540-1100) (400-1500)
(pCi/m3) 20.5 km Drinking Water Gross Heta (28) 1.6 (14/14) R-6 Gilcrest 1.6 (14/14) 0.74 (14/14) 0 (pCi/L) (0.35-2.70) City Water 1.7 (0.35-2.70) (0.38-1.1) 9.3km R-6 Gilcrest 11-3 (28) 1046 P/14) -
1040(2/14) $20 (2/14) O City Water (380-1700) (380-1700) (420 610) 9.3km Gamma Spectrometry Drinking Water R-6 Gilcrest 0.93 (1/14)
Cs-134 (28) 0.93 (1/I4) -
0
. City Water -
9.3km
Table II.G.1 Radiological Environmental Monitoring Program Annual Summary Fort St. Vrain Station, Platteville, Colorado Medium or Type and Total Facility Locations Adjacent Locations with liighest Annual Mean Reference Number of Pathway Samples Number of Mean (O Range . Locations Mean Name Mean Locations Mean Nonroutine (Unit of Analyses (f)I Range Distance & Range' (f)I Range Reported measurement) Performed Direction Mw mc.ts Drinking Water Cs-137 (28) 2.7(14/14) _ R-3 Ft. Collins 3.0 (14/14) 3.0(14/14) 0 (1.4-4.4) City Water (1.9-5.0) (1.9-5.0) 45.1 km Zr-95 (28) - - - - -
0 Nb-95 (28) 2.2 (914) _
R-6 Gilerest 2.2 (9 14) 2.0 (3/14) 0 (I.2-2.9) City Water (1.2-2.9) 93 km (l.2-23)
~ -
, Co-58 (28) - - -
0 Mn-54 (28) 2.0 (1/14) _
R4 Gilcrest 2.0 (1/14) 1.4 (4/14) O City Water (0.87-l.9) 93 km Zn-65 (28) - - - - -
0 Fe-59 (28) 8.2 (2/14) _ R-6 Gilcrest 8.2 (2/14) 4.1 (2/14) 0 (4.4-12) City Water (4.4 12) (3.5-4.7) 93 km Co-60 (28)
~
R-3 Ft. Collins 1.2 (2/14) 1.2 (2/14) O City Water (1.1-13) (1.1-13) .
45.1 km Ba-140 (28) 6.2 (3!!4) -
R-6 Gih 3.5 (1/14) 6.2 (3/14) O City Water (3.4-Il) 93 km I3'4'III La-140 (28) 7.0 (3/14) R-6 Gilcrest 4.0 (1/14) 7.0 (3/14)
O City Water (3.9-12) 93 g (3.9-12) n- we' - - -_ _ . _ _ _ e + e- + - + +. _ ___m _m
- ___ --. ______-_
Table II.G.1 Radiological Environmental Monitoring Program Annual Summary Fort St. Vrain Station, Platteville, Colorado Afedium or Type and Total Facility Locations Adjacent Locations with IIighest Annual hfcan Reference Number of Pathway Samples Number of hfcan (f) Range Locations Mean Name Mean Locations Mean .Jonroutine (Unit of Analyses (f)I Range Distance & (f)I Range Reported RanEc measurement) Performed Direction hicasurements Surface Water 11-3 (31) < 380 470 (1/12) A-25 l' arm Pond 470 (1/12) < 380 0 (pCi/L) 2.2 km Sect Gamma Spectrometry Surface Water Cs-134 (31) 2.0 (1/12) A-21 St. Vrain 470 (1/6) -
0 (pCi/L) Creek 2.4 km Sec II Cs-137 (31) 3.4 (11/12) 3.3 (10/12) F-20 St. Vrain 4.1 (5/6) 2.6 (6/7) 0 (2.2-5.9) (1.7-5.5) Creek (3.2-5.9) 2.7 (1.9-3.4) 21.5 km Sec 16 m
A-21 St. Vrain Zr-95 (31) 4 3 (1/12) 5.5 (1/12) 5.5 (t/6) 3.9 (1/7) 0 2.4 km Sec 11 Nb-95 (31) 2.2 (3/12) F-20 St. Vrain 2.6 (2/6) 3.0 (2/12) I.7 (3/7) 0 (1.5-2.9) Creek
- (23-2.9)
(3.0-3.0) 21.5 km Sec 16 (1.4-1.9)
Co-58 (31) 1.6 (3/12) -
F-20 St. Vrain Creek 1.7 (2/6) -
0 (1.2-2.2) 21.5 km Sec 16 (1.2-2.2) 13 (2/12) F-19 S. Platte 2.2 (1/6) 1.6 (1.7)
Mn-54 (31) 1.9 (2/12) 0 *
(1.2-2.4) - 1.2 km Sec 4 ..
(1.5-2.2_
Zn-65 (31) - - - - -
5 3 (3/12) F-20 St. Vrain 63(1/6)
Fe-59 (31) 6.0 (2/12) -
0 (5.0-5.6) Creek (5.6-63) 21.5 km Sec 16 Co-60 (3I) - - - - -
0
_ _ - _ _ _ _ _ _ _ _ _ . _ _ _ - _ - - _ _ _ _ _ _ _ _ - - _ _ _ _ _ _ _ - - _ . . _ _ _ _ _ ____ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ . _ _ _ _ _ _ _ _ _ _ _ _ _ - _ - - - _ _ i- - v.-rw e .e= .r --W- - - - .t=6- 4 ---nr< + y
Table II.G.1 Radiological Environmental Monitoring Program Annual Summary Fort St. Vrain Station, Platteville, Colorado Afedium or Type and Total Facility Locations Adjacent Locations with liighest Annual Mean Reference Number of Pathway Samples Number of Afcan (O Range Locations hlcan Name Mean Locations hlcan Nonroutine (Unit of Analyses (OIRange Distance & Range (0 1Range Reported measurement) Performed Dire:* ion hicasurements Ba-140 (31)
~
R-10 S. Plane 12 (10) 4.0 (1/12) 12 (10) 0
@ CO 60 10.1 km La-140 (31)
~
R-10 S. Platte 4.6 (1/12) 13 (1 0) 13 (10) 0
@ CO 60 10.1 km Ground Water 11-3 (3) < 400 - - -
< 390 0 (PCi/L)
Gamma Spectrometry y Ground Water Cs-134 (3) - - - - -
0 (PCi/L)
Cs-137 (3) 4.4 (2/2) _
F-16 Russell 4.4 (1/2) 4.0 (1/l)
Ranch 0
(2.7-6.1) (2.7-2.6) 1.5 km Sec I Zr-95 (3) - - - - -
0 Nb-95 (3) - - - - -
0 j Co-58 (3) 1.4 (1/2) -
F-16 R sell I.4 (1/2) 1.2 (1/2) 0 1.5 km Sec 1 -
Mn-54 (3) - - - - -
0 Zn-65 (3) - - - - -
0 Fe-59 (3) - - - - -
0 Co-60 (3) - - - - -
0 l
Ba-140 (3) - - - - -
0
-x---. - _ . - - . - _ - - - _ _ _ _ - - - - _ _ _ - _ _ , . - - - - - - - _ _ _ _ _ _ - - - - - - - _ - _ _ . . _ - _ _ - _ _ . - - - , _ _ _ _ _ - - - - - - , - w
Table II.G.I Radiological Environmental Monitoring Program Annual Summary Fort St. Vrain Station, Platteville, Colorado Medium or Type and Total Facility Locations Adjacent Locations with flighest Annual Mean Reference Number of Pathway Samples Number of Mean (O Range Locations Mean Name Mean Locations Mean Nonroutine (Unit of Analyses (f)I Range Distance & Range (O IRange Reported iro. m m ent) P= formed Direction , MeAsuienents Ground Water La-140 (3) - - - - -
0 (PCi/L)
Milk (pCi/L) ^ 4 "#""'
11-3 (46) -
490(8/38) 540(2/8) 480 (1/8) 0 Dairy (39 % 20) 7.1 km Sec 6 (450-620)
Gamma Spectrometry Milk (pCi/L)
R-8 Borba Dairy Cs-134 (46) -
I3 (lf8) 1.3 (l18) 0 23 km Cs-137 (46) - 4.4 (33/38P A-18 Boos Dann 4 8 (M) 4.0 (7i8) 0 d (2.1-6.2) Sec 2 4.7 km (3.6-6 0) (2.7-5.1) 7.7(l/38) A-I8 Boos Dairy Ba-140 (46) -
7.7 (l/8) -
0 Sec 2 4.7 km 8'8 II#38I Ad8 U*IU La-140(86) -
8.8 (1/8) -
0 Sec 2 4.7 km
- 1. Mean and Range based upon detectable measurements only.
Fraction (f) of detectable measurements at specified locations is indicated in parentheses.
4 u_.__ *
.gM Table II.G.2 Summary Table of Arithmetic Means and Standard Deviations for Selected Sample Types -
1992 1993 1994 1995 19 %
X 1.96s f I96s X 196s X 1.96s : X- 1.96s 11-3 Atmospheric Water Vapor (pCi/L)
Facility 980 830 430 130 520 90 420 120 200 750 Reference 780 530 420 50 630 350 410 110 90 740 Gross Beta - Air (fChn') >
Facility 25 15 24 . 14 28 92 . '19 11 23 6.7 Reference 25 12 22 14 24 53 17 -_ 9.5 22 14 Cs 137 O Facility 1.0 0.22 1.6 2.9 0.89 0.61 1.1 0.82 0.16 __ l.2 Reference - 1.1 0.40 13 23 0.98 0.95 1.2 1.0 0.48 0.54 11-3 Drinking Water (pCi/L) 5 Gilcrest 550 90 < 430 50 410 680 590 470 10 1200 Ft. Collins 500 50 < 420 40 < 380 10 < 370 < 380 50 760 Gross Beta Drinking Water (pCi/1.)
Gilcrest 4.5 23 3.2 2.9 2.6 1.7 1.0 1.0 1.6 1.5 Ft. Collins 0.90 031 0.92 0.72 1.2 0.48 0.77 035 0.74 039 ,
Cs-137 Air (fCihn')
Gilcrest 3.4 1.1 3.8 3.1 4.2 23 2.6 1.6 2.7 1.9 Ft. Collins 3.4 0.88 3.4 23 3.7 2.4 2.8 1.8 3.0 1.7 i
. _ . . - . -- - - . . .,,m. .~ ~ -
. - - . , _ _ . _ _ ~ , - . . _ - _ . ~ , .
Table II.G.2 Summary Table of Arithmetic Means and Standard Deviations for Selected Sample Types 1992 1993 1994 1995 1996 K 1.96s X 1.96s X 1.96s f 1.96s X 1.%s 11-3 Surface Water (pCi/L)
Efiluent 770 590 < 420 20 1500 640 590 420 < 390 740-Downstream 990 860 < 420 50 390 550 < 390 -
< 390 640 Upstream 640 0 < 450 200 570 770 < 390 -
< 390 610 Cs-137 d Effluent 3.6 1.4 3.6 2.8 4.3 2.3 3.2 2.2 3.4 2.6 Downstream 3.5 1.2 3.8 2.2 4.5 2.5 2.8 2.2 2.9 2.2 Upstream 3.8 0.89 3.6 2.3 4.1 2.8 3.5 1.6 2.6 1.7 -
1I-3 Milk (pCi/L)
Facility 760 590 < 430 140 760 660 < 430 -
50 750 Reference 590 90 < 420 20 550 450 < 430 -
130 510 l
O m.
4
Table II.H.1 Tritium Concentrations in F-16 Well. Water for 1996 Date Collected Concentration (pCi/L) 01/05 < 460 01/12 < 460 01/20 < 390 01/27 h 02/03 h 02/10 h 02/17 h 02/24 < 400 03/02 < 380 03/09 420 (440)*
03/15 < 390 03/23 < 400 03/30 490 (480) 04/06 < 380 04/13 460 (450) 04/20 < 390 04/27 < 390 05/04 < 390 05/09 < 390 05/16 < 390 05/23 < 390 05/30 < 390 06/06 670 (480) 06/13 1010 (460) 1 06/20 < 380 1 06/28 820 ( 590) 07/03 480 (590) l h - Sample not collected (Well pump frozen)
- 1.960 - Due to counting statistics 74 i
i l
L111. . Radiological Environmental Monitoring Program l g ' A. Sample Collection and Analysis Schedule Table F-1 in the Offsite Dose Calculation Manual'(ODCM) outlines the sampling design, the collection frequency and the type of analysis for all environmental samples. It should be repeated that this schedule was adopted January 1,1984, and while different in c'ertain aspects from ithe previous schedule, has as its intent the same objective. That objective was to document the radiation and radioactivity levels in the critical pathways of possible dose to humans. Such data -
was' necessary to demonstrate Fort St. Vrain. radioactive effluents produce environmental concentratidns that are within appropriate environmental protection limits and at the same time are as low as reasonably achievable.
During 1996, there were no changes in the sampling program. Iodine-131 analysis was dropped at the beginning of 1993 for milk and air samples. The operational phase of the facility i
ended permanently in August of 1989 and due to the short half-life ofI-131 (8.05 days), there is no
. longer any inventory of I-131 present. Fish and beef samples were not collected since only 6 '
o L ' months of liquid releases were perfonned associated with decommissioning, and food product o i sampling was not conducted since termination of releases occurred prior to the fall harvest.
Table Ill.A.2 lists the LLD concentration values for each sample type and radionuclide measured in this report. These LLD values are the actual values pertinent to the sample sizes, counting yields, and counting times used in the project. Typical decay periods were used in the
, calculations. 'It should be noted that the LLD values are in all cases equal to or less than those required by the ODCM.
n y ).
- 75 a -
,l Table F-3 of the ODCM' lists the USNRC reporting level for each sample type and I radionuclide. No results exceeded the reporting level in 1996.
j Table F-4 of the ODCM gives the description of each sampling location by number, sector, l and distance from the site. Each o'. these sampling locations (except certain reference locations) l can be identified on scale maps (Figures III.B.1 and III.B.2). Topographical maps showing greater detail, as well as photographs of principal sampling sites that are on file in the CSU laboratory. !
Note that the REMP program terminated prior to conducting the annual land-use census. In the past, a few residents in the sampling sectors up to a distance of 8 km from the plant have cows or gor.ts that could be used for personal milk consumption. However, from direct discussion with these persons,' this is not a common practice and all cow milk produced is transported to commercial processors. The milk produced locally is diluted by a large milk shed, processed and distributed over a large area for consumption. Elevated radionuclide concentrations in milk samples due to Fort St. Vrain station effluents have never been detected during either the operational or decommissioning phases.
d 76
TABLE III.A.1 DECOMMISSIONING RADIOLOGICAL ENVIRONMENTAL MONITORING PROGRAM Exposure Pathway Number of Samples Sampling Type and Frequency and/or Sample and Locations Collection Frequency of Analysis AIRBORNE Tritium and Samples from seven Continuous sampler Liquid Particulates locations: operation with scintillation sample collection counting for Four samples from offsite weekly or as tritium in water locations (in different required by dust vapor extracted sectors) of the highest loading, whichever from silica gel on historic calculated is more frequent. each sample annual average airborne collected.
X/Q and resultant ground level D/Q. Particulate-Sampler: Gross y
One sample from the beta radioactivity vicinity of a community following filter having the highest change, gamma historic calculated isotopic quarterly annual average ground on composite (by level D/Q. location) .
- Two samples from control location 15 to 30 kilometers (10 to 20 miles) distant and in the direction of the lowest -
historic calculated X/Q.
- If gross beta activity is greater than ten times the yearly mean of control samples for any medium, gamma isotopic analysis should be performed on the individual samples.
l O
m -__ r _ __ i__i- _ - - - - - _ . _ - _ . - . _ _ _ _ _ . _ _ _ -
_ ,.. . . . _ . _. . . ._.. _ .. . s, , _
. $ : .f 273 y
TABLE III . A.1' - (Continued)~
DECOMMISSIONING RADIOLOGICAL ENVIRONMENTAL MONITORING PROGRAMi -
r
.-x
- Exposure Pathway - " Number-of Samples _ . ? Sampling- Type and Frequency '
. . and/or Sample and~ Locations Collection Frequency of Analysis '
~
DIRECT' RADIATION Forty-one stations with - Quarterly Gamma.' Exposure. Rate' r
~ two or more dosimeters to on each dosimeter be placed as follows: 1)- collected.
an inner ring of stations -
in the general area of the site boundary.and an ;
outer ring._in the~1.6 to- '
8 kilometer range from-the site with at- least one station in each sector'of.each ring; others shall-be-placed.in .
. ;;g special interest areas such~as. population
-3 centers, nearby ..
residences, echools, and :i control stations. ..
N I
e 7 4
i
'y' '{
9' s
_w m.
t I
i
.4
-.76-s--.Sm-w-m-<- c_,'~-..-
UL.-..,.*w.rA-,-..er~... . . . -. .- sm.m ~ - .
. ~ ,. ,A,-s ----.-..v_.. . > r - - - -. , . , , _ . . - - . . . /__..-
TABLE III.A.1 (Continued)
DECOMMISSIONING RADIOLOGICAL ENVIRONMENTAL MONITORING PROGRAM Exposure Pathway Number of Samples Sampling -Type and Frequency and/or Sample and Locations Collection Frequency of Analysis WATERBORNE Samples from 9 locations:
Surface One sample upstream from each stream, one sample Samples collected' Gamma isotopic downstream from each monthly analysis and stream tritium on each sample collected o
one sample in immediate area of farm pond Composite continuous Gamma isotopic discharge sample over one week analysis and g period. Composite tritium on each collected weekly sample collected E
e.
___.___.________..-________-______..__m___m_ _ _ _ _ _ _ _ _ _ _ _ _ . _ .
TABLE III.A.1 (Continued)
DECOMMISSIONING RADIOLOGICAL ENVIRONMENTAL MONITORING PROGRAM Exposure Pathway Number of Samples Sampling Type and Frequency and/or Sample and Locations Collection Frequency of Analysis Ground Samples from two sources Quarterly Gamma isotopic and down gradient from the tritium on each plant sample collected Drinking One sample from the Weekly Tritium, gross nearest drinking water beta *, and gamma supply which could be isotopic analyses affected by facility's on composite, every discharge 2 weeks Gne sample from a control Weekly Tritium, gross location beta *, and gamma isotopic analyses on composite, every 2 weeks SEDIMENT Samples from 2 locations:
One sample from downstream area with Semi-annually Gamma isotopic existing or potential analyses on each recreational value sample collected One sample in effluent -
pathway Monthly Gamma isotopic analyses on each sample collected
- If gross beta activity is greater than ten times the yearly mean of control samples for any medium, gamma isotopic analysis should be performed on the individual samples.
-. _____m-
- -- ., 7 7
n'
^
~
TABLE III.A.1 (Continued) -
I
' DECOMMISSIONING RADIOLOGICAL ENVIRONMENTAL MONITORING' PROGRAM'
- Exposure: Pathway. - Number of-Samples Sampling- Type and Frequency- '
- .and/orl Sample and Locations. Collection Frequency -of Analysis ~
. MILK Samples-from 5 locations:
One sample from each dairy Monthly i Gamma-is'otopic and' in at least-two locations, trit-ium on each -
within 5 kilometers. sample collected.
One sample ~from each dairy in at-least two locations Monthly Gamma isotopic and' between 5 to~8 kilometers. -tritium-on each-sample. collected.-
One sample from.a dairy at' a control location 15 to 30 kilometers distant and Monthly Gamma;isotopi~c and in the direction of the' tritium on each~ '
lowest historic' calculated sample collected.
X/Q.
.s S
-v 4
_-__m v a_m_ c-_c a -_ ____s_-- - *-1m u _ . _ - __=-_-r- -
,_ - __ __ w ,_m --ew,-
TABLE III.A.1 (Continued)
DECOMMISSIONING RADIOLOGICAL ENVIRONMENTAL MONITORING PROGRAM Exposure Pathway Number of Samples Sampling and/or Sample Type and Frequency and Locations Collection Frequency of Analysis FISH Samples from 3 locations:
One in vicinity of Semi-annually Gamma isotopic effluent discharge point, analyses on each one sample upstream and sample collected one sample downstream.
FOOD PRODUCTS One sample each of at Annually, at time of Gamma isotopic least five varieties of harvest analyses on each vegetables that are sample type commonly grown in the collected area for human consumption which is irrigated by R water in which liquid plant wastes have been discharged and/or are in the direction of the historic highest calculated X/Q.
Tissue samples (muscle and Semi-annually liver) from one head of Tritium and gamma beef cattle that graze isotopic analyses near effluent discharge on each sample pathway.
collected -
., . ~ . . . ..... - . .. . ... . . - . .-_ - . . . . - . . = . . - - . . . - - . . - - . . , - - . .. - ... . _ - - . - .
TABLE Ill.A.2 DETECTION CAPABILITIES FOR ENVIRONMENTAL SAMPLE ANALYSIS I LOWER LIMIT OF DETECTION (LLD)
' -i
- Analysis - Water - Airbome Fish Milk Food Products Sediment (pCi/l) . Particulate -(pCi/kg, wet) (pCi/l) :(pCi/kg, wet)- _(pCi/kg, dry) -
or Gas i
(fCi/m') -i Gross Beta 4 5 N/A N/A .N/A N/A 11-3 2000 N/A N/A N/A N/A 3
N/A Cs-134 15 9 130 15 60 150 .
Cs-137 18 8 150 18- 80 180 Mn-54 15 N/A 130 N/A N/A N/A -
Co-60 ' 15 N/A 130 N/A N/A N/A >
Zn-65 .30 N/A 260 N/A N/A N/A' !
1 NOTE:This list does not mean that only these nuclides are to be detected and reported. Other. peaks which are measurable and identifiable, together with the above nuclides, shall also be identified and reported.
}
i f
i 4
i- t v
x
- I r
. - - - .,# -, - -r---- - - . .v - - . - . ..__-__=i-w --e.- . . > - .--e-, .-r,v-- ,r,mm,.+ c -u=_, ~ .- <r - e . er u- - -_ m
TABLE Ill.B.1 RADIOLOGICAL ENVIRONMENTA.L MONITORING PROGRAM SAMPLING SITE DESCRIPTIONS.
(F: Facility Area 0-1.6 km. A: Adjacent Area 1.6-8 km. R: Reference Area)
Exposure Site No. Location Description (see map) Sector Distance, km Pathway Direct Radiation F-1 Pole by gate to Goosequill road on dirt extension of CR 21. I 1.3 F-2 21st pole N ofditch on dirt extension of CR21 just before road drops 2 1.1 down to river bottom.
F-3 17th pole N of ditch on dirt extension of CR 21 or first pole N of 3 0.7 East-West road.
g F-4 15th pole N of ditch on dirt extension of CR 21, S of pump road, 4 0.7 midway between F-3 and F-5.
F-5 1 Ith pole N of ditch on dirt extension of CR 21, near drive to pump 5 0.6 house.
F-6 8th pole N of ditch on dirt extension of CR 21, by 6 0.8 East-West concrete Ditch, S of bridge F-7 Old dairy bam,1st pole N after crossing ditch on dirt extension of 7 1.2 CR 21.
F-8 lst pole W of pump house on N side of road,0.4 km E of CR 19-1/2. 8 1.3 F-9 Pole East of first shed south side ofintersection ofCR 19-1/2 and CR 9 1.5 34.
F-10 Pole on NW comer ofintersection ofdirt extension of CR 19 and 34. 10 1.5
. _ _ _ . _ _ . . . _ _ - - _. . . _ . _. .....-..m . . -...- . . - _ _ _ - . _ -.-. .,. . _ -. . _ --- _ . _-.
TABLE III.B.1 - '
- RADIOLOGICAL ENVIRONMENTAL MONITORING PROGRAM .
- SAMPLING SITE DESCRIPTIONS (F: Facility Area 0-1.6 km. A: Adjacent Area 1.6-8 km. R: Reference Area)
Direct Radiation . F-11 7th pole N ofintersection ofdirt extension of CR 19 with CR 34. -11 -1.2 F-12 0.5 km S of FSV Visitor Center, take dirt road W across field, go into 12 - 1.0 -
farmyard of Aristocrat Angus. (If chain across road, enter from CR q 36). TLD is located on pole at SE comer of corral across from '
Aristocrat Angus office. -i F-13 Take first dirt road S of Visitor Center. Go W across railroad tracks, - 13' O.5 :
follow dirt road to metal staircase going down off dike. TLD is taped to railing.
F-14 2nd pole 0.1 km S intersection CR 36-1/2 and Rd 19. 14 1.5 F-15 2nd pole 0.7 km S ofintersecdon of CR 38 on CR 19. 15 .l.5 F-16 Pole at NE corner of potato cellar at 3 Bar Ranch (Russell's). I 1.2
[
F-17 Visitor Center, on N end ofcross beam over entrance. . 13 0.2 . ,
F-18 Pole closest to house on SW corner,17250 CR 19-1/2. The address . 16 0.8 of 17250 is taped to the Mountain Bell underground cable warning -'
post. <
A-1 Pole on NW comer ofintersection of CR 44 and CR 21. 1 - 6.7 . .
i w -, -e . --w-- + -.-.- -ev.a----r - e e-* h---o--w-*+,+v-u-- a <+m-+9- w - , - -6+-w w-rt m m m e w seureeww+=W-+ ww'%-- . 4- ew P w tr.4r v n s -9'r -vT -'+e'*tw a =i-N+'**'#T' to-w- -
t 'twei
TABLEIII.B.1 RADIOLOGICAL ENVIRONMENTAL MONITORING PROGRAM SAMPLING SITE DESCRIPTIONS (F: Facility Area 0-1.6 km. A: Adjacent Area 1.6-8 km. R: Reference Area)
Exposure Site No. Location Description (see map) Sector Distance,km Pathway -
Direct Radiation A-2 Pole on NE corner ofintersection of CR 42 and CR 25-1/2 2 6.8 A-3 Pole on NE comer ofintersection of CR 42 and CO 60. 3 7.5 A-4 1st pole NE ofintersection of CR 29 and CR38, take CR 29 E out of 4 7.4 Gilcrest to CR 38.
A-5 SE corner of CR 34 and CR 29. Taped to road sign on SW comer of- 5 7.2 intersection.
E A-6 Pole on S side of CR 32 near drive to dairy 6 7.1 13278 CR 32.
A-7 Niles Miller dairy. 0.4 km E of US 85 on 12854 CR 30. TLD is 7 7.3 located on pole at NE comer of house.
A-8 On CO 66 (CR 30) farm on S side of road (address 9476) Pole in 8 4.7 front of house.
A-9 Comer of CO 66 (CR 30) and CR 19, Miller produce stand. Second 9 4.6 pole S on CR 19, on E side of road. .
A-10 Pole on SE comer at intersection CR 26-1/2 and CR 15. 10 .7.8 A-11 At intersection of CO 66 and CR 13,2nd pole N ofintersection en E 11 7.2 -
side of CR 13.
A-12 On CR 34, pole E of house N of Lake Thomas 2 km from I-25. 12 7.2
___ _ .. -_ . _ . . . _ . . . .. ._ _ y_ . .
l; -
+ -:
l 1
+
l .,
l i
- a
' ~
TABLEIII.B.1 3
_ RADIOLOGICAL ENVIRONMENTAL MONITORING PROGRAM =
- SAMPLING SITE DESCRIPTIONS -
~
i
'(F: Facility Area 0-1.6 km. A: Adjacent Area 1.6-8 km. R- Reference Area) -!
.I Exposure Site No. Location Description (see map) Sector Distance, km. :
Pathway -
Direct Radiation A-13 Pole opposite lake, N of silage pits E side of CR 13 2.9 km N of CR 13 -5.8
~
- 34. '
- i A-14 Intersection of CR 13 and CR 40, NW corner.
14' '.6.9'.
A-15 Intersection of CR 42 and CR 15, NW corner. 15- I 6.7) a A-16 Intersection of CR 44 and CR 19, SW corner. 16 6.8 A-17 Platteville school (S edge of town on Main Street) pole on NW 6 5.9
- 5. comerjust outside school intramural field.
j A-20 1st pole N of white picket fence and driveway into turkey farm on S 9- 2.5 end of building that is parallel with CR 19. .
?
R-1 Milliken School, on CR 21-1/2. TLD is located on pole located at 93 SE corner of Lola Park, across the street from school. _
l R-2 Johnstown school (Letford Elementary), tum left at school crossing 10.8 .
on Idaho St. onto Jay Ave. and proceed to school. TLD is located on pole at SE corner of ma'm entrance to school on W side of town. .- ,
R-3 CSU dairy farm on W Drake, N of Vet Hospital, Fort Collins, CO. 45.1 -
Pole is E of hay barn next to railroad tracks on east side of road.' j R-4 Air sampler corner US 287 and CO 66, Longmont Dairy Store. TLD . 20.5 i is located on pole directly behind air sampler. !
4
____-sa_-_
_____sem --waws + . - - + _. . - _ . . .r,-em...-.,ws,- .r.ne.-.. 2< ,..m-,-,.-.._4e me.---- - +., .._.-s.w 4 ww+-..+-, r- .wm., . . #.m.g,_.w.-.,,:_._,~.e-m.,. .-cum.. ,,
TABLEIII.B.1 RADIOLOGICAL ENVIRONMENTAL MONITORING PROGRAM SAMPLING SITE DESCRIPTIONS (F: Facility Area 0-1.6 km. A: Adjacent Area 1.6-8 km. R: Reference Area)
Exposure Site No. Location Description (see map) Sector Distance, km Pathway Direct Radiation R-7 Behind Gilcrest School quonset auditorium, pole on SW end of 9.3 school property,just before garage.
Sediment F-1 Sediment from confluence of Goosequill Ditch and Jay Thomas 1 1.3 Ditch.
R-10 Sediment from S. Platte River at bridge on CO 60. 10.1 Airbome F-7 Farm at intersection of CR 21 and CR 34. Air sampler is located on 7 1.5 g west side of shop. Silica gel in mailbox next to air sampler.
F-9 First shed along drive at end of Rd 19-1/2 intersection with Rd 34. 9 1.5 Silica gelis located in shed.
F-16 Potato cellar at 3 Bar Ranch (Russell's). Silica gel in mailbox on tree 16 1.2 to S ofpump.
A-19 Hunting cabin between Goosequill ditch and Platte River. Air 1 1.7
~
sampler is on W side ofcabin, silica gel is in box on tree north of air sampler.
R-11 Air sampler located on the North side of Johnstown Services 10.5 Building, silica get is inside mailbox.
R-3 Colorado State University Dairy, W Drake Rd., Fort Collins, CO. W 45.1 side of shed directly N of main dairy building. Silica get inside mailbox.
TABLE III.B.1 RADIOLOGICAL ENVIRONMENTAL MONITORING PROGRAM SAMPLING SITE DESCRIPTIONS (F: Facility Area 0-1.6 km. A: Adjacent Area 1.6-8 km. R: Reference Area)
Exposure Site No. Location Description (see map) Sector Distance, km Pathway Airbome R-4 Intersection of US 66 and US 287, E side ofdairy store, north edge of 20.5 Longmont. Silica gel is in mailbox attached to utility pole.
Waterbome F-19 S Platte at dam located on dirt road E ofpump house #3 directly E of 4 1.2 Surface reactor.
F-20 St. Vrain creek on Rd 19-1/2,0.3 km from discharge into S< "-ain 16 1.5 Creek. Directly N of reactor.
g A-21 St. Vrain creek at bridge on Rd 34, E of Rd 17. 1I 2.4 R-10 S. Platte river at bridge on CO 60 where highway hasjust turned and 10.1 headed south. '
A-25 Farm Pond outlet. Continuous samplerlocated in green box adjacent i 2.2 to the green shed on N end ofpond.
Ground F-16 Well behind residence at 3 Bar Ranch (Russell's),17578 WCR 19- 1 1.2 1/2.
R-5 Well at 108 S. Grace, Milliken. 9.5 -
Drinking R-6 Gilcrest U.S. Post Omce located on Birch St. and Rd 40 offHwy 85. 9.3 Water taken from utility sink inside Post Omce or outside hydrant.
R-3 CSU dairy W. Drake Rd, Fort Collins, CO, North of Vet Hospital. 45.1 Water sample is taken from hydrant in milking parlor or hydrant ~ 50 yds. north of air samtiler.
TABLE Ill.B.1 RADIOLOGICAL ENVIRONMENTAL MONITORING PROGRAM ,
. SAMPLING SITE DESCRIPTIONS (F: Facility Area 0-1.6 km. A: Adjacent Area 1.6-8 km. R: Reference Area)
Exposure Site No. Location Description (see map) Sector Distance, km Pathway Milk A-18 Boos Dairy,11258 W Rd 40, W of US 85 behind modular home. 2 4.7 A-23 Leroy Odenbaugh Dairy,11733 Rd 36, W of Rd 25. 4- 4.1 A-6 Henrickson Dairy,13278 Rd 32 (Grand Avenue),1.6 km E of US 85. 6 7.1 A-28 Colorado Dairy. 7388 Hwv. 66 10 5.5 A-26 James Docheff Dairy,4513 WCR 32 11 7.8 g' R-8 Borba Dairy,2252 S CR 7, located off exit 255, West ofI-25. 22.5 Fish A-25 Farm pond outlet. 1 2.2 Fish F-19 S. Platte at dam located on dirt road E of pump house 3 directly E of 4 1.1 plant.
R-10 S. Platte River a: bridge on CO 60. 10.1 Food Products A-27 11247 Weld Courty Road 36. 4 4.3 A-28 Residence 1139') WCR 40-1/2. 2 5.3 .
R-6 Hemandez Produce Stand, Highway 85, Gilcrest 9.6 F-16 Houston or Russell Ranch 15 or 16- 1.2
- - - - _ _ _ - - - - - - - - _ _ - - - - - e'
i Figure III.B.1 Close in Sampling Locations I l
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Figure III.B.2 Adjacent and Reference Sampling Locations JOHNS ptf /
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- IV. Errata for 1995 REMP Report '
j 2
i i
The gross beta Facility and Reference means for the particulate activity in air for the Fourth : ;
- Quaner of 1995 (Table II.B.l(d)) were incorrectly reported. The correct means are 24(10) fCi/m3 l l
l ' for the Facility area, and 21(8.3) fCi/m3 for the Reference area. The correct yearly means for 1995 l i
4 are 22(14) fCi/m3 for the Facility Area, ac.d 21(12) fCi/m3 for the Reference area. The corrected 1
- . version of Table II.B. l(d) is provided on the following page. !
i
- 3. ,
4- r i
i l 4 l l
j l
A 1
k
- j. !
i i
c j 93 l
o Table II.B.l(d) Concentrations of Long-lived Gross Beta Particulate Activity in Air (fCi/m3)
Revision 1, December 1996 4* Quarter 1995 Collection Facility Reference Dates F-7 F-9 F-16 A-19 R-3 R-4 R-1I 10/07 17 (1.0)* 17(0.96) 17 (0.88) 16 (0.97) 15 (0.98) 16(0.98) 15 (0.91) 10/14 26(1.2) 26(1.2) 26(1.1) 26(1.2) 25 (1.3) 2I(1.1) 22 (1.1) 1O!20 23 (l3) 24 (l3) 25 (l.2) 25 (13) 27(I.5) 22 (l3) 22 (l.2) 10/27 19 (1.0) 20(1.0) 19 (0.97) 22 (1.1) 21(1.2) 18(1.1) 16 (0.94)
I1/04 27(1.1) 27(1.1) 28(1.1) 27(1.1) 26(1.2) 23 (1.2) 23 (1.0) 1I/II 25 (1.1) 23 (1.0) 24 (1.0) 24(1.1) 24(1.2) 20(1.1) 22 (1.1) 1I/18 19(1.0) 20 (0.96) 2I (0.95) 2 I (1.1) 18(1.1) 15 (0.98) 18 (0.89) g II/26 27(1.1) 25 (1.1) 28(1.1) 29(12). 25 (1.2) 22 (1.0) 21(1.0) 12/02 21(1.2) 12 (1.1) 18 (1.1) 19 (1.2) 15 (1.2) 12(0.98) 14 (1.0) 12/09 24 (1.2) 2I (1.1) 22 (1.0) 23 (1.2) 17(1.1) 20(1.1) 20(1.1) 12/15 27(l.7) 25 (13) 23 (l 2) 25 (I.4) 20(l.4) 17 (l.1) 2I (1.2) 12/22 b 19(1.1) 23 (1.2) 29 (1.4) 24 (13) 22 (1.2) 20(1.1) 12/29 b b 38(13) 42 (1.6) 28(1.4) 28(1.2) 30(13)
X 23 22 24 25 22 20 20 1.960 6.8 8.1 10 3 11.8 8.5 7.7 1
7.7 .
Max: 42 x(l.%o): 24(I0) Max: 30 Min: 12 x(1.96o): 2I(8.3) n: 49 Min: 12 n: 39
- 1.960 (Due to counting statistics) b- Sample Missing at Site
. _ _ _ _ _ _ __ _ _ _ _ _ . _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ - . _ _ _ _ _ _ _ . . _ . .. _ . .